-
1.
Evaluating adherence, tolerability and safety of oral calcium citrate in elderly osteopenic subjects: a real-life non-interventional, prospective, multicenter study.
Rondanelli, M, Minisola, S, Barale, M, Barbaro, D, Mansueto, F, Battaglia, S, Bonaccorsi, G, Caliri, S, Cavioni, A, Colangelo, L, et al
Aging clinical and experimental research. 2024;36(1):38
-
-
-
-
Free full text
-
Plain language summary
The occurrence of fractures and osteoporosis are significant concerns in elderly adults, as ageing remains one of the primary risk factors for these conditions. While the incidence of fracture and risk may vary, the incidence of fragility fractures significantly increases with advancing age, particularly after the age of 50 years. This study's aim was to evaluate the adherence, tolerability, and safety of calcium citrate administration in an "outpatient" population in routine clinical practice. This study was a non-interventional, prospective, multicentre study. Two-hundred and sixty-eight individuals (comprised 245 females (91.4%) and 23 males (8.6%)) were enrolled. Results showed a high rate of adherence to calcium citrate supplementation over a one-year period in osteopenic elderly subjects. Additionally, the incidence of adverse reactions was low (3.9%), further emphasizing the tolerability of calcium citrate. Authors concluded that future studies designed to assess the long-term impact of calcium citrate supplementation on hard endpoints, such as bone density, fractures/falls, quality of life measures and adherence are needed.
Expert Review
Conflicts of interest:
None
Take Home Message:
- The occurrence of fractures and osteoporosis are significant concerns in older adults, as ageing remains one of the primary risk factors for this condition.
- Calcium supplementation, usually with vitamin D, is a recommended complement to other specific pharmacological treatments of osteoporosis.
- This non-interventional, prospective multicentre study suggests a 91% adherence to calcium citrate supplementation over one year in elderly osteopenic patients with generally good (80%) tolerability and 4% reporting gastrointestinal adverse effects.
Evidence Category:
-
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
B: Systematic reviews including RCTs of limited number
-
X
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Introduction
A non-interventional, prospective multicentre study was conducted to evaluate the adherence, safety, and tolerability of calcium citrate supplementation in elderly osteopenic subjects.
Method:
A total of 231 Caucasian female (91%) and male (8%) participants with a median age of 70 received 500mg of calcium citrate supplementation daily for one year. Adherence was assessed based on tolerability, compliance, and persistence. Safety evaluations included monitoring of adverse reactions (ARs), physical examinations, and clinical laboratory evaluations.
Results
A total of 222 out of 231 participants (96%) completed the study. Nine subjects did not return for assessments or complete their diaries.
The primary and secondary findings of this study were as follows:
- An average adherence of 91% of oral calcium citrate supplementation was observed which was higher than the reported reference rate of 57% (p = 0.0179).
- Subjects with adherence <80% experienced a higher frequency of adverse events compared to those with adherence >80% (32/77; 42% vs 16/145%, (p = 0.0001).
- Gastrointestinal ARs were the most commonly reported, with constipation comprising 50% of all reported ARs.
- Reductions in systolic (130.7 ± 16.9 mmHg to 127.9 ± 14.5 mmHg) (p = 0.0102) and diastolic blood pressure 79.5 ± 8.7 mmHg to 77.4 ± 8.6 mmHg (baseline to V2) (p = 0.0116) were observed from baseline to the second visit.
- Positive changes were also noted in nutritional status (p = 0.0116), circulatory system disorders (p = 0.0001), and muscles/skeleton disorders (p = 0.0067) from baseline to post-baseline visit.
Conclusion:
This study revealed a 91% adherence to calcium citrate supplementation over one year in older adults with osteopenia, Additionally, the 4% incidents of ARs reported were related to gastrointestinal disorders.
Clinical practice applications:
- The prevalence of osteoporosis rises as individuals age, with approximately 10% of women at 60 years, 20% at 70 years, and 40% at 80 years.
- Calcium supplementation, usually with vitamin D, is a recommended complement to other specific pharmacological treatments of osteoporosis.
- The safety of calcium supplements remains controversial regarding an increased risk of cardiovascular events. Therefore, it is essential to investigate the safety profile of calcium in these populations.
- This study reported adherence, tolerability, and safety of calcium citrate supplementation in osteopenic elderly patients with 4% of patients reporting gastrointestinal adverse effects.
Considerations for future research:
- This study was conducted on 91% Caucasian females and 8% males with a mean age of 70 years therefore, there is a need to include more male and Asian participants from various age groups in further research.
- Future studies are needed to assess the long-term impact of calcium citrate supplementation on bone density, fractures, and quality of life.
Abstract
BACKGROUND Osteoporosis is a common concern in the elderly that leads to fragile bones. Calcium supplementation plays a crucial role in improving bone health, reducing fracture risk, and supporting overall skeletal strength in this vulnerable population. However, there is conflicting evidence on the safety of calcium supplements in elderly individuals. AIM: The aim of this study was to evaluate the adherence, safety and tolerability of calcium citrate supplementation in elderly osteopenic subjects. METHODS In this non-interventional, prospective, multicenter study, subjects received daily 500 mg calcium citrate supplementation for up to one year. Adherence was calculated based on compliance and persistence. Safety was assessed through adverse reactions (ARs), deaths, and clinical laboratory evaluations. RESULTS A total of 268 Caucasian subjects (91.4% female, mean age 70 ± 4.5 years) participated in the study. Mean adherence to treatment was 76.6 ± 29.5% and half of subjects had an adherence of 91% and ~ 33% of participants achieved complete (100%) adherence. ARs were reported by nine (3.9%) subjects, primarily gastrointestinal disorders, with no serious ARs. The frequency of all adverse events (including ARs) was significantly higher in subjects with adherence of < 80% (41.6%; 32/77) vs. those with adherence ≥ 80% (11%; 16/145, p < 0.0001). Both systolic and diastolic blood pressure decreased from baseline to follow-up visit (change of -2.8 ± 13.9 mmHg, p = 0.0102 and -2.1 ± 10.4 mmHg, p = 0.0116, respectively). CONCLUSION This study demonstrated favorable adherence to calcium citrate supplementation in elderly osteopenic subjects. The occurrence of ARs, though generally mild, were associated with lower adherence to calcium supplementation.
-
2.
Calorie restriction modulates the transcription of genes related to stress response and longevity in human muscle: The CALERIE study.
Das, JK, Banskota, N, Candia, J, Griswold, ME, Orenduff, M, de Cabo, R, Corcoran, DL, Das, SK, De, S, Huffman, KM, et al
Aging cell. 2023;22(12):e13963
-
-
-
-
Free full text
Plain language summary
Reducing calorie intake by 12% has been shown in one randomised control trial (RCT) called the Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE) trial, to result in both fat and muscle loss but without any changes to muscle strength and function. The present study aimed to take 90 of the individuals from the original CALERIE study to understand the mechanisms behind this. The results showed that after 12 months individuals who were given a calorie reduced diet lost significant amounts of weight compared to control and this loss was maintained after 2 years. This included muscle loss, but despite this, there was no change in muscle strength of individuals on calorie reduced diet. Genetic analysis showed that genes are involved in muscle quality and anti-ageing. It was concluded that 2 years of calorie restriction resulted in both fat and muscle loss but did not compromise muscle function. The upregulation of genes involved in muscle quality and anti-ageing may be responsible for this.
Expert Review
Conflicts of interest:
None
Take Home Message:
- CR can aid weight loss and sustain losses long-term. Some lean muscle loss may also be seen, but this does not mean that muscle function has been compromised
- CR can trigger molecular and cellular mechanisms involved in skeletal muscle, sustaining functionality during a weight loss programme.
Evidence Category:
-
X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Introduction
The Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE™) randomised control trial (RCT) showed that 12% caloric restriction (CR) induced muscle loss, without compromising muscle strength. This analysis of 90 individuals from that study aimed to determine the mechanisms behind this.
Methods
- The CALERIE study was an RCT that assessed the effects of 25% CR over 2 years compared to an ad libitum control group
- This study ran alongside the CALERIE study and took skeletal muscle biopsies from a subset of 90 individuals at baseline, 12 months, and 24 months from the CR group and ad libitum control group
- This yielded 162 muscle biopsies over 2 years
- Skeletal muscle was taken from the vastus lateralis muscle and lean leg mass, and muscle strength were assessed
- In addition, RNA was extracted, and gene expression assessed.
Results
- Participants on CR lost significant amounts of weight (P=<0.001) at 12 months, with no further improvements at 2 years. Quantity or range of weight loss data was not provided
- Control participants maintained their weight over 2 years
- There were no changes in muscle strength in CR individuals despite a significant loss of muscle mass (no P value given)
- Although adjustments for change in lean leg mass resulted in less of a decline in the isokinetic muscle strength test compared to control (average power P=0.0058 and peak torque P=0.0144)
- RNA analysis showed 797 genes were overexpressed and 206 underexpressed in CR compared to control
- CR was associated with enhanced anti-ageing mechanisms with genes such as those involved in androgen receptor signalling, autophagy, circadian rhythms, DNA repair, FOXO mediated transcription, and mitochondrial biogenesis all upregulated and inflammatory genes downregulated
- These changes were responsible for the positive effect on muscle quality in individuals in the CR group.
Conclusion
- It was concluded that 2 years of CR preserved muscle function despite muscle mass loss, through upregulation of the genes involved in muscle quality and anti-ageing.
Clinical practice applications:
- Healthcare professionals may consider a 12% CR diet for individuals who would like to lose weight and maintain its loss long-term, without compromising muscle function
- Although lean muscle mass may be lost, muscle function should not be affected, but should be monitored to ensure functionality.
Considerations for future research:
- The possible effects of combining CR with muscle strength exercises should be considered for future research to determine if muscle mass loss is prevented and whether this impacts further fat loss.
Abstract
The lifespan extension induced by 40% caloric restriction (CR) in rodents is accompanied by postponement of disease, preservation of function, and increased stress resistance. Whether CR elicits the same physiological and molecular responses in humans remains mostly unexplored. In the CALERIE study, 12% CR for 2 years in healthy humans induced minor losses of muscle mass (leg lean mass) without changes of muscle strength, but mechanisms for muscle quality preservation remained unclear. We performed high-depth RNA-Seq (387-618 million paired reads) on human vastus lateralis muscle biopsies collected from the CALERIE participants at baseline, 12- and 24-month follow-up from the 90 CALERIE participants randomized to CR and "ad libitum" control. Using linear mixed effect model, we identified protein-coding genes and splicing variants whose expression was significantly changed in the CR group compared to controls, including genes related to proteostasis, circadian rhythm regulation, DNA repair, mitochondrial biogenesis, mRNA processing/splicing, FOXO3 metabolism, apoptosis, and inflammation. Changes in some of these biological pathways mediated part of the positive effect of CR on muscle quality. Differentially expressed splicing variants were associated with change in pathways shown to be affected by CR in model organisms. Two years of sustained CR in humans positively affected skeletal muscle quality, and impacted gene expression and splicing profiles of biological pathways affected by CR in model organisms, suggesting that attainable levels of CR in a lifestyle intervention can benefit muscle health in humans.
-
3.
The Effects of Polyphenols on Bone Metabolism in Postmenopausal Women: Systematic Review and Meta-Analysis of Randomized Control Trials.
Salvio, G, Ciarloni, A, Gianfelice, C, Lacchè, F, Sabatelli, S, Giacchetti, G, Balercia, G
Antioxidants (Basel, Switzerland). 2023;12(10)
-
-
-
-
Free full text
Plain language summary
Women who are post-menopause are at a higher risk of osteoporosis due to lower levels of the hormone oestrogen. Oestrogens promote bone building and limit breakdown. In addition, oestrogen protects the bones against oxidative stress, which can cause further bone breakdown. Polyphenols, which are naturally occurring chemicals found in fruits and vegetables, may prevent oxidative stress and subsequent bone breakdown. This systematic review and meta-analysis of 21 randomised control trials aimed to determine the effect of polyphenol supplementation on post-menopausal bone density. The results showed that polyphenol supplementation had no effect on bone density in the spine, leg, hip, or across the whole body. If polyphenol supplementation extended beyond 2 years, there was evidence of an improvement in spinal bone density. Supplementation also increased one biomarker associated with bone building and decrease one associated with its breakdown. It was concluded that polyphenol use is not recommended to improve bone health in postmenopausal women. This study could be used by healthcare professionals to understand polyphenol supplementation is ineffective for the prevention of osteoporosis and other lifestyle modifications should be considered.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Postmenopausal women are susceptible to decreased BMD due to lower oestrogen levels and oxidative stress.
- Although polyphenols have an antioxidant effect, supplementation does not seem to affect bone mineral density in postmenopausal women.
- Post-menopausal women should consider other lifestyle modifications to reduce the risk of osteoporosis.
Evidence Category:
-
X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Introduction
- Postmenopausal, low oestrogen levels can decrease osteoclastic activity, increase osteoclastic apoptosis, and make bones more susceptible to oxidative stress, which in turn increases osteoclastogenesis and decreases osteoblastogenesis.
- Polyphenols from fruits and vegetables can have an antioxidant effect. They have been shown in vitro to enhance osteoblastic activity through effects on endothelial function and have been associated with a lower risk of fractures.
- This systematic review and meta-analysis aimed to evaluate the effect of polyphenol supplementation on postmenopausal bone mineral density (BMD).
Methods
- 21 randomised control trials were included.
- The primary outcome assessed the effect of polyphenols on BMD.
- The secondary outcome assessed the effect of polyphenols on bone turnover markers; deoxypyridinoline, osteocalcin, alkaline phosphatase, and pyridinoline.
- 18 studies reported on lumbar BMD, 12 on femoral neck BMD, and 7 on total body BMD.
- Study durations ranged from 3-36 months
Results
- Polyphenols did not affect BMD of the lumbar spine (sMD: 0.21, 95% CI [−0.08 to 0.51], p = 0.16), femoral neck (sMD: 0.16, 95% CI [−0.23 to 0.55], p = 0.42), total hip (sMD: 0.05, 95% CI [−0.14 to 0.24], p = 0.61), or whole body (sMD: −0.12, 95% CI [−0.42 to 0.17], p = 0.41). However, a sub-analysis based on studies longer than 24 months showed that lumbar BMD was improved (sMD: 1.00, 94% CI [0.19 to 1.81], p=0.02).
- Treatment duration did not affect femoral neck BMD, total hip BMD, or whole-body BMD.
- Polyphenols did not affect deoxypyridinoline or osteocalcin levels, however they did increase bone specific alkaline phosphatase (sMD: 1.27, 95% CI [1.13 to 1.42], p < 0.0001) and decrease pyridinoline (sMD: −0.58, 95% CI [−0.77 to −0.39], p < 0.0001).
- There was high heterogeneity amongst the studies and 14 showed high or unclear risk of bias.
Conclusion
- Polyphenol use is not recommended as the sole preventative therapy for postmenopausal osteoporosis.
Clinical practice applications:
- A polyphenol rich diet is not recommended to improve BMD and fracture risk in postmenopausal women.
- Other lifestyle modifications with more robust research should be recommended instead.
Considerations for future research:
- Future studies would be interesting in women in perimenopause to determine if life stage affects efficacy of polyphenols.
Abstract
Osteoporosis is a condition favored by the postmenopausal decline in estrogen levels and worsened by oxidative stress (OS). Polyphenols are natural compounds abundantly found in fruits and vegetables, and they exert antioxidant and hormonal effects that could be useful in osteoporosis prevention, as suggested by epidemiological studies showing a lower incidence of fractures in individuals consuming polyphenol-rich diets. The aim of our meta-analysis is to evaluate the effects of polyphenols on bone mineral density (BMD, primary endpoint) and bone turnover markers (BTMs, secondary endpoint) in postmenopausal women. Twenty-one randomized control trials (RCTs) were included in our analysis after in-depth search on PubMed, EMBASE, and Scopus databases. We found that supplementation with polyphenols for 3-36 months exerted no statically significant effects on BMD measured at lumbar spine (sMD: 0.21, 95% CI [-0.08 to 0.51], p = 0.16), femoral neck (sMD: 0.16, 95% CI [-0.23 to 0.55], p = 0.42), total hip (sMD: 0.05, 95% CI [-0.14 to 0.24], p = 0.61), and whole body (sMD: -0.12, 95% CI [-0.42 to 0.17], p = 0.41). Subgroup analysis based on treatment duration showed no statistical significance, but a significant effect on lumbar BMD emerged when studies with duration of 24 months or greater were analyzed separately. On the other hand, we found a significantly slight increase in bone-specific alkaline phosphatase (BALP) levels (sMD: 1.27, 95% CI [1.13 to 1.42], p < 0.0001) and a decrease in pyridinoline (PD) levels (sMD: -0.58, 95% CI [-0.77 to -0.39], p < 0.0001). High heterogeneity among studies and unclear risk of bias in one third of the included studies emerged. A subgroup analysis showed similar effects for different duration of treatment and models of dual-energy X-ray absorptiometry (DXA) scanner. More robust evidence is needed before recommending the prescription of polyphenols in clinical practice.
-
4.
Nicotinamide adenine dinucleotide metabolism and arterial stiffness after long-term nicotinamide mononucleotide supplementation: a randomized, double-blind, placebo-controlled trial.
Katayoshi, T, Uehata, S, Nakashima, N, Nakajo, T, Kitajima, N, Kageyama, M, Tsuji-Naito, K
Scientific reports. 2023;13(1):2786
-
-
-
-
Free full text
Plain language summary
Nicotinamide adenine dinucleotide (NAD+) is a coenzyme that plays a crucial role in energy metabolism and different biological processes. Sirtuins (SIRT1) are NAD+-dependent deacetylases, an enzyme that plays a key role in enhancing metabolic efficiency. Nicotinamide mononucleotide (NMN) is a precursor to NAD+. NMN supplementation may help to reduce the risk of developing metabolic diseases and cardiovascular diseases. This randomised, double-blinded, and placebo-controlled, parallel trial investigated the effects of 12 weeks of 125 mg NMN supplementation on metabolic health parameters, including CVD risk factors, blood NAD+ metabolites level, and SIRT1 expression in middle-aged men and women. Serum nicotinamide was significantly higher and arterial stiffness was lower in the NMN test group of middle-aged men and women after 12 weeks of NMN supplementation. The results of the study indicate that the administration of 250mg of nicotinamide mononucleotide (NMN) daily for an extended period is considered safe and well-tolerated. Healthcare professionals can use this finding to understand the significant implications of the use of NMN as a potential therapeutic agent in individuals seeking to improve their metabolic and cardiovascular health. Further robust studies are required to evaluate the effects of NMN supplementation due to the limitations and high baseline variability between the participants of this study.
Expert Review
Conflicts of interest:
None
Take Home Message:
- As we age, NAM levels decline, which could have a negative effect on cardiovascular health.
- Middle-aged adults may like to consider NMN supplementation to improve NAM metabolism and arterial stiffness.
- However, without data on CVD events, it is difficult to determine actual risk reductions.
Evidence Category:
-
X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Introduction
- Nicotinamide adenine dinucleotide (NAD+) is a coenzyme involved in metabolism. When we age, NAD+ levels decline resulting in poorer metabolism and age-related disease such as cardiovascular disease (CVD). Nicotinamide mononucleotide (NMN) is a precursor in the biosynthesis of NAD+.
- This double-blind, randomised control trial aimed to determine the effect of supplementing NMN on NAD+ levels, CVD risk factors and sirtuin 1 (SIRT1) expression, which relies on NAD+ for adequate functioning.
Methods
- 36 healthy male and female individuals aged between 40-65 years of age were assigned to either NMN (125mg/day) or placebo for 12 weeks.
- One capsule was taken twice per day after meals.
- Serum nicotinamide (NAM), NAD+, NMN, advanced glycation end products (AGES), 8-hydroxydeoxyguanosine (8-OHdG) and SIRT1 mRNA expression were measured.
- The condition of blood vessels (arterial stiffness) was also assessed using the ankle brachial index (ABI).
- In a sub-analysis, individuals with hypertension, above average body mass index (BMI), or blood glucose level were also assessed for blood vessel condition using the ABI.
Results
- The results showed that from baseline serum NAM decreased in the placebo group (P=0.014), whereas it increased in the NMN group (P=0.006). This resulted in an increase in the NMN group compared to placebo (P=0.037).
- Interestingly serum NAM was lower in the NMN group compared to placebo at baseline (P=0.001).
- There was no statistically significant difference in ABI with NMN supplementation.
- Amongst those with hypertension there was also no change in ABI. However, those with high BMI or blood glucose, there was an improvement in vascular condition compared to placebo (P=<0.007 and P=0.019 respectively).
- 8-OHdG, SIRT1 mRNA and AGEs remained unchanged by NMN supplementation
Conclusion
- NMN supplementation enhanced NAD+ metabolism in middle-aged adults.
- It also relieved arterial stiffness and reduced CVD risk factors.
Clinical practice applications:
- Apparently healthy middle-aged adults who would like to activate NAD metabolism and decrease their risk for CVD, should consider 12-week supplementation with NMN (125mg/day).
- ABI should be monitored to ensure desired effects.
- It is unclear as to the effects of NMN supplementation after 12-weeks.
Considerations for future research:
- Future research should consider longer supplementation duration and/or adding in a follow-up period to determine duration of effect.
- Different supplemental doses should also be researched to determine an optimal dose.
Abstract
Many animal studies have shown that oral administration of the nicotinamide adenine dinucleotide (NAD+) precursor nicotinamide mononucleotide (NMN) prevents the reduction of NAD+ levels in organs and tissues, helping alleviate aging-related diseases. However, there are very few clinical reports of NMN supplementation in humans. Thus, this study aimed to investigate the influence of a 12-week NMN oral supplementation on biochemical and metabolic health parameters. A 12-week randomized, double-blind, placebo-controlled, parallel-group clinical trial was conducted. A total of 36 healthy middle-aged participants received one capsule of either 125 mg NMN or placebo twice a day. Among the NAD+ metabolites, the levels of nicotinamide in the serum were significantly higher in the NMN intake group than in the placebo group. Pulse wave velocity values indicating arterial stiffness tended to decrease in the NMN intake group. However, no significant difference was found between the two groups. Long-term NMN supplementation at 250 mg/day was well tolerated and did not cause adverse events. NMN safely and effectively elevated NAD+ metabolism in healthy middle-aged adults. Additionally, NMN supplementation showed potential in alleviating arterial stiffness.
-
5.
Mediterranean diet and structural neuroimaging biomarkers of Alzheimer's and cerebrovascular disease: A systematic review.
Gregory, S, Pullen, H, Ritchie, CW, Shannon, OM, Stevenson, EJ, Muniz-Terrera, G
Experimental gerontology. 2023;172:112065
-
-
-
-
Free full text
-
Plain language summary
Nearly a million people in the UK have Alzheimer's disease, the most common type of dementia. Mediterranean diet (MedDiet) adherence is associated with healthy brain ageing, a reduced stroke risk, and a lower incidence of dementia. Seven studies were included in this review to evaluate the effects of MedDiet on hippocampal volume and white matter hyperintensity volume, predictors of stroke and dementia. This systematic review did not reveal any associations between MedDiet adherence and hippocampal volume. However, there was a significant negative relationship between MedDiet adherence and white matter hyperintensity volume in two of the studies included. It is necessary to conduct more robust studies to investigate the associations between MedDiet adherence and structural brain imaging findings and understand the mechanisms behind dementia and other cerebrovascular diseases. This study could provide healthcare professionals with valuable information about the effects of increased MedDiet adherence on brain health, including its potential to delay neurodegenerative disease progression.
Expert Review
Conflicts of interest:
None
Take Home Message:
Due to inconclusive results on the associations between MedDiet adherence and AD and cerebrovascular related structural neuroimaging findings, specific recommendations for the MedDiet cannot be made on the basis of this study until further research has been completed.
Evidence Category:
-
X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Background:
Changes in hippocampal volume (HV) and white matter intensity volume (WMIV) have been identified as structural neuroimaging biomarkers of neurodegenerative disease such as Alzheimer’s Disease (AD) and Cerebrovascular disease (CVD) respectively. Evidence has shown adherence to the Mediterranean Diet (MedDiet) has been associated with reduced risk for strokes. This review evaluated the MedDiet in relation to HV and WMIV.
Methods:
The review followed PRISMA guidelines and was registered on PROSPERO. Literature searching resulted in seven studies published between 2012 and 2022, which met the inclusion criteria. Six studies analysed cross-sectional data and one analysed longitudinal data. The NIH Quality Assessment Tool for Observational and Cross-Sectional Studies was used to assess risk of bias.
Overall, the studies were rated as low-risk of bias with details of the research question, participant group exposure and outcome variables included. Due to moderate to high heterogeneity in some studies, a meta-analysis was deemed unsuitable and narrative synthesis was conducted to present the results.
Results:
Mean participant age ranged from 53.19 to 80.3 years and volunteers were healthy or had subjective cognitive decline and a few participants had dementia (n=46).
Hippocampal Volume:
Four studies included 20,077 participants and found no significant associations between MedDiet adherence and hippocampal volume. All four studies were cross-sectional from larger cohort studies. To establish causative relationships longitudinal and RCT trials are required.
White Matter Hyperintensity Volumes:
Four studies included 1938 participants. Two studies found a significant negative association between MedDiet and WMHV, demonstrating higher Mediterranean Scores were associated with lower level of WHMV. The other two studies found no significant associations.
Although the review methodology with a piloted search strategy was considered a key strength, the lack of meta-analysis as planned in the a priori protocol, due to minimal eligible studies and high heterogeneity was a limitation as well as the restriction of brain imaging outcomes.
Conclusion:
Overall, these results are inconclusive on the associations between the MedDiet and HV and WMHV, and identify a gap in the knowledge, therefore further research such as RCT’s remains a priority to further understand the impact diet may have on neuroimaging markers of AD and CVD.
Clinical practice applications:
There were no significant associations between MedDiet adherence and HV, which was surprising given the evidence stating adherence to the MedDiet is associated with a lower incidence of dementia and stroke. However all four studies were cross-sectional studies and in order to detect causal associations, longitudinal and RCT’s are needed. Two studies did show a significant association between higher MedDiet adherence and lower WMHV, whereas two studies reported no significant associations.
Caution needs to be taken when recommending the MedDiet specifically for a reduction in HV and WMHV until further research has been undertaken.
Considerations for future research:
Future research should consider:
- larger cohorts and participants from the Mediterranean region where lifelong adherence to the MedDiet is more likely.
- looking at other risk factors to include obesity, lack of activity, poor sleep quality and stress.
- evaluating different socio-economic status, which has been shown to impact dietary behaviour.
- alternative imaging outcomes such as cortical thinning, PET amyloid and tau.
- . gold standard for methodology in particular dietary analysis and scanning and outcome derivation.
Abstract
Previous studies have demonstrated an association between adherence to the Mediterranean diet (MedDiet) and better cognitive performance, lower incidence of dementia and lower Alzheimer's disease biomarker burden. The aim of this systematic review was to evaluate the evidence base for MedDiet associations with hippocampal volume and white matter hyperintensity volume (WMHV). We searched systematically for studies reporting on MedDiet and hippocampal volume or WMHV in MedLine, EMBASE, CINAHL and PsycInfo. Searches were initially carried out on 21st July 2021 with final searches run on 23rd November 2022. Risk of bias was assessed using the NIH Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Of an initial 112 papers identified, seven papers were eligible for inclusion in the review reporting on 21,933 participants. Four studies reported on hippocampal volume, with inconclusive or no associations seen with MedDiet adherence. Two studies found a significant association between higher MedDiet adherence and lower WMHV, while two other studies found no significant associations. Overall these results highlight a gap in our knowledge about the associations between the MedDiet and AD and cerebrovascular related structural neuroimaging findings.
-
6.
Muscle Mass Changes After Daily Consumption of Protein Mix Supplemented With Vitamin D in Adults Over 50 Years of Age: Subgroup Analysis According to the Serum 25(OH)D Levels of a Randomized Controlled Trial.
Kang, Y, Kim, N, Lee, Y, An, X, Chung, YS, Park, YK
Clinical nutrition research. 2023;12(3):184-198
-
-
-
-
Free full text
Plain language summary
Sarcopenia is an age-related decrease in muscle mass and strength and increases the risk of falls and death. Protein intake and vitamin D are important for the maintenance of muscle mass, and the amino acid leucine plays a role in the regulation of muscle protein turnover. The aim of this 12-week double-blind, randomised, placebo-controlled trial was to evaluate the efficacy of a supplement containing protein, vitamin D, leucine and calcium for maintaining muscle mass, strength and physical functioning in healthy Koreans aged 50-80 years. Increases in muscle mass were seen in those with low vitamin D levels (< 30 ng/ml) but not in those with higher vitamin D levels. No differences were observed in muscle strength and physical functioning. The authors concluded that a supplement containing protein, including high levels of leucine, vitamin D and calcium may be of benefit for muscle mass to middle-aged and older adults with low vitamin D levels.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Consider supplementing protein in combination with leucine, vitamin D and calcium in middle-aged or older adults with insufficient vitamin D levels for prevention of sarcopenia.
Evidence Category:
-
X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Introduction
- Sarcopenia increases the risk of falls and death
- Protein and vitamin D are important for maintaining muscle mass whilst leucine is involved in regulating muscle protein turnover
- The aim of this study was to evaluate the effects of a supplement containing protein, vitamin D, leucine and calcium on muscle mass, physical functioning, muscle strength, and physical ability in middle-aged and older adults.
Methods
- Double-blind, randomised, placebo-controlled trial, with a duration of 12 weeks. Included 120 healthy Koreans aged 50-80 years
- Participants were assigned to “insufficient” subgroup if vitamin D levels were <30ng/ml and to the “sufficient” subgroup if vitamin D was 30ng/ml or higher
- Intervention: 2.5g powder (containing 20g protein (90% milk/10% soya, incl. 3g leucine), 800 IU vitamin D, 300 mg calcium) mixed into beverage of choice twice a day. Control: isocaloric placebo powder
- Primary outcome: Muscle mass determined by dual-energy X-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA)
- Secondary outcomes: Muscle strength (femoral muscle and grip strength); physical functioning (short physical performance battery (SPPB), International Physical Activity Questionnaire (IPAQ)).
Results
- At baseline, age of participants in the “sufficient” intervention subgroup was higher than that of the “sufficient” control subgroup (p=0.02)
- Increase in vitamin D levels in intervention group relative to control group, in both sufficient and insufficient subgroups (difference in changes between groups 11.5 ng/ml and 13.9 ng/ml, respectively, both p=0.00)
- No difference in change in muscle index as measured by DXA between groups
- In the “insufficient” subgroup, BIA increases in muscle mass were seen when normalised by height (p=0.037) and weight (p=0.05)
- No differences in changes in physical functioning or muscle strength between groups.
Conclusion
- The authors conclude that a supplement containing protein, with high levels of leucine, vitamin D and calcium may be of benefit for muscle mass to middle-aged and older adults with insufficient vitamin D levels.
Clinical practice applications:
- Middle-aged and older adults with insufficient vitamin D levels may gain muscle mass through supplementation of protein, leucine, vitamin D and calcium
- Middle-age and older adults with sufficient vitamin D levels do not appear to benefit from the same intervention.
Considerations for future research:
- Longer-term studies may help identify whether increases in muscle mass lead to improved physical functioning over time
- A study combining supplementation and exercise may help identify additive or synergistic effects.
Abstract
UNLABELLED Early prevention of sarcopenia can be an important strategy for muscle maintenance, but most studies target subjects at slightly pre-sarcopenic state. Our previous paper describes the effect of protein supplements rich in leucine and vitamin D on muscle condition, and in this paper, we performed a sub-analysis to evaluate who benefitted the most in terms of improvement in muscle health. A 12-week randomized clinical trial of 120 healthy adults (aged 50 to 80) assigned to an intervention group (n = 60) or control group (n = 60) were analyzed. Subjects in the intervention group received, twice per day, a protein supplement containing (per serving) 800 IU of vitamin D, 20 g of protein (3 g of total leucine), 300 mg of calcium, 1.1 g of fat, and 2.5 g of carbohydrate. The subjects were classified into 'insufficient' and 'sufficient' groups at 25-hydroxyvitamin D (25[OH]D) value of 30 ng/mL. The skeletal muscle mass index normalized to the square of the skeletal muscle mass (SMM) height (kg/m2) increased significantly in the 'insufficient group' difference value of change between weeks 0 and 12 (Δ1.07 ± 2.20; p = 0.037). The SMM normalized by body weight (kg/kg, %) was higher, but not significantly, in the insufficient group (Δ0.38 ± 0.69; p = 0.050). For people with insufficient (serum 25[OH]D), supplemental intake of protein and vitamin D, calcium, and leucine and adequate energy intake increases muscle mass in middle-aged and older adults and would be likely to exert a beneficial effect on muscle health. TRIAL REGISTRATION Clinical Research Information Service Identifier: KCT0005111.
-
7.
Effect of Vitamin D3 Supplementation on Acute Fracture Healing: A Phase II Screening Randomized Double-Blind Controlled Trial.
Slobogean, GP, Bzovsky, S, O'Hara, NN, Marchand, LS, Hannan, ZD, Demyanovich, HK, Connelly, DW, Adachi, JD, Thabane, L, Sprague, S
JBMR plus. 2023;7(1):e10705
-
-
-
-
Free full text
Plain language summary
Almost half of all adult patients with fractures are vitamin D deficient. The aim of this double-blind, randomised, placebo-controlled trial was to evaluate the efficacy of different vitamin D regimens on the healing of acute tibia and femur fractures. 102 18-50-year-old patients were enrolled in the study and randomised to receive a) two high doses (150,000 IU) at time of injury and after 6 weeks, b) 4000 IU daily, c) 600 IU daily or d) placebo for 3 months. After 3 months, there were no statistically significant differences between the 3 intervention groups with respect to clinical or radiographic outcomes of fracture healing. The authors report a significantly better clinical, but not radiographic, outcome for 4000 IU per day versus placebo with a p-value of 0.15 (note: generally, to be considered statistically significant, p should be < 0.05). Similar results were observed after 12 months. There was no significant correlation between vitamin D levels and fracture healing. The authors concluded that high dose vitamin D may confer a modest benefit for fracture healing but that this requires confirmation from a larger clinical trial.
Expert Review
Conflicts of interest:
None
Take Home Message:
- The evidence base for the use of vitamin D supplements in isolation to support fracture healing is weak.
Evidence Category:
-
X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Introduction
- Low levels of vitamin D can have negative effects on bone metabolism and healing of fractures
- Almost half of all adult fracture patients are vitamin D deficient
- The aim of this study was to evaluate the effectiveness of supplementing vitamin D3 (VD3) to improve tibia and femur fracture healing.
Methods
- Four-arm, double-blind, randomised, phase II screening, placebo-controlled trial
- 102 adult patients (aged 18-50 years) with a non-osteoporotic tibial or femoral shaft fracture were randomised into 1 of 4 treatment groups
- Just over half (56%) of participants were vitamin D3 deficient at baseline
- Intervention groups: 1) 150,000 IU VD3 loading dose at injury and at 6 weeks (high loading) plus daily placebo; 2) placebo loading doses plus 4000 IU VD3 daily (high dose); 3) placebo loading doses plus 600 IU VD3 daily (low dose); 4) placebo loading dose plus placebo daily
- Duration: 3 months intervention, further 9 months follow-up. Vitamin D levels were assessed at 6 weeks and 3 months.
Primary outcome measures at 3 months:
- Clinical assessment using the Function IndeX for Trauma (FIX-IT)
- Radiographic assessment using the Radiographic Union Score for Tibial fractures (RUST).
Secondary outcomes: as above at 6, 9 and 12 months.
Results at 3 months:
- No statistically significant difference between high loading and high dose, high and low dose or low dose and placebo for either clinical or radiological assessment (all p-values ≥0.4)
- Post-hoc analysis of any dose vs placebo showed no significant difference with either clinical or radiological assessment (all p-values ≥0.25)
- Post-hoc analysis of high dose vs placebo showed no significant difference for radiological assessment (p=0.76) whilst it was reported as statistically significant for clinical assessment with p=0.16, with a benefit of VD3 supplementation.
- Similar results were seen at 12 months with reported benefit of high dose VD3 for fracture healing with p=0.18
- Vitamin D levels improved in all 3 VD3 groups from baseline to 6 weeks
- There was no statistically significant correlation between fracture healing and vitamin D level.
Conclusion
The authors conclude that VD3 supplementation may be of modest benefit for fracture healing, but further, larger trials are needed to confirm this.
Clinical practice applications:
- When working with clients who present with a fracture, it should be noted that the evidence for benefit of vitamin D supplementation alone for fracture healing is weak.
Considerations for future research:
- Larger studies to increase the statistical power to detect smaller benefits are required
- Larger studies may also identify differences in potential benefits between patient populations with different baseline levels of vitamin D.
Abstract
Nearly half of adult fracture patients are vitamin D deficient (serum 25-hydroxyvitamin D [25(OH)D] levels <20 ng/mL). Many surgeons advocate prescribing vitamin D supplements to improve fracture healing outcomes; however, data supporting the effectiveness of vitamin D3 supplements to improve acute fracture healing are lacking. We tested the effectiveness of vitamin D3 supplementation for improving tibia and femur fracture healing. We conducted a single-center, double-blinded phase II screening randomized controlled trial with a 12-month follow-up. Patients aged 18-50 years receiving an intramedullary nail for a tibia or femoral shaft fracture were randomized 1:1:1:1 to receive (i) 150,000 IU loading dose vitamin D3 at injury and 6 weeks (n = 27); (ii) 4000 IU vitamin D3 daily (n = 24); (iii) 600 IU vitamin D3 daily (n = 24); or (iv) placebo (n = 27). Primary outcomes were clinical fracture healing (Function IndeX for Trauma [FIX-IT]) and radiographic fracture healing (Radiographic Union Score for Tibial fractures [RUST]) at 3 months. One hundred two patients with a mean age of 29 years (standard deviation 8) were randomized. The majority were male (69%), and 56% were vitamin D3 deficient at baseline. Ninety-nine patients completed the 3-month follow-up. In our prespecified comparisons, no clinically important or statistically significant differences were detected in RUST or FIX-IT scores between groups when measured at 3 months and over 12 months. However, in a post hoc comparison, high doses of vitamin D3 were associated with improved clinical fracture healing relative to placebo at 3 months (mean difference [MD] 0.90, 80% confidence interval [CI], 0.08 to 1.79; p = 0.16) and within 12 months (MD 0.89, 80% CI, 0.05 to 1.74; p = 0.18). The study was designed to identify potential evidence to support the effectiveness of vitamin D3 supplementation in improving acute fracture healing. Vitamin D3 supplementation, particularly high doses, might modestly improve acute tibia or femoral shaft fracture healing in healthy adults, but confirmatory studies are required. The Vita-Shock trial was awarded the Orthopaedic Trauma Association's (OTA) Bovill Award in 2020. This award is presented annually to the authors of the most outstanding OTA Annual Meeting scientific paper. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
-
8.
Effects of an educational intervention on frailty status, physical function, physical activity, sleep patterns, and nutritional status of older adults with frailty or pre-frailty: the FRAGSALUD study.
Casals, C, Ávila-Cabeza-de-Vaca, L, González-Mariscal, A, Marín-Galindo, A, Costilla, M, Ponce-Gonzalez, JG, Vázquez-Sánchez, MÁ, Corral-Pérez, J
Frontiers in public health. 2023;11:1267666
-
-
-
-
Free full text
Plain language summary
Frailty and pre-frailty are associated with an increased risk of premature mortality. Factors involved in the development of frailty include physical activity, sleep and nutrition. The aim of this 6-month randomised controlled trial was to evaluate the effects of an educational programme on frailty, physical function, physical activity, sleep and nutritional status. 166 community-dwelling individuals aged 65 years or over with frailty or pre-frailty were randomised to either receive a health education programme consisting of 4 group sessions in the first month which included guidelines for physical activity, nutrition and cognitive training as well as the promotion of psychological and social wellbeing and 6 follow-up calls over 6 months or their usual healthcare (control). Compared to the control group, the intervention group had significant reductions in frailty score, exhaustion and fatigue score, increase in gait speed and improvements in various physical function tests. The intervention group also showed significant improvements in mini nutritional assessment compared to the control group although this was not associated with significant changes in anthropometric parameters. There was a significant increase in awakenings in the control group whilst this parameter did not change in the intervention group, whilst there were no changes in other sleep parameters. The authors concluded that the simplicity, affordability and effectiveness of the health education programme may contribute to healthy ageing.
Expert Review
Conflicts of interest:
None
Take Home Message:
To improve frailty and physical functioning, a comprehensive programme may be effective, which includes:
- Nutrition
- Physical exercise
- Cognitive training
- Promotion of social and psychological wellbeing.
Evidence Category:
-
X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Introduction
- Frailty and pre-frailty increase the risk of premature mortality but are reversible
- The aim of this study was to evaluate the effects of a health education programme on frailty status in frail or pre-frail older persons.
Methods
- Randomised controlled trial
- Participants: 166 community-dwelling individuals aged 65 years or over with frailty or pre-frailty living in Spain were enrolled, 163 completed the study (80 in intervention and 83 in control group)
- Four weekly group sessions which included guidelines for physical activity, nutrition and cognitive training as well as the promotion of psychological and social wellbeing and 6 follow-up calls over 6 months versus usual healthcare (control).
Results
- Baseline demographics: The educational group consisted of more women (p=0.001), had a younger average age (p=0.019), lower height (p=0.001) and a higher average education level (p=0.013) compared to the control group.
Effects on intervention group:
- Reductions in frailty score (p<0.05 vs baseline and change vs change in control group), with 30% of participants in the intervention group no longer being classified as frail or pre-frail in contrast to none in the control group
- Reductions in fatigue and exhaustion score (p<0.05 vs baseline and change vs change in control group)
- Increase in gait speed and improvements in various physical function tests (all p<0.05 vs baseline and change vs change in control group)
- Improvements in mini nutritional assessment (p<0.001 vs baseline and change vs change in control group)
- Improvement in sleep behaviour demonstrated by an increase in awakenings in the control group (p<0.05 vs baseline and change vs change in intervention group) whilst this parameter did not change in the intervention group.
No effects (vs control) on:
- Anthropometric parameters/unintended weight loss
- Other sleep parameters
- Physical activity expenditure and physical activity score
- Hand grip strength.
Conclusion
This affordable and simple health education programme is effective in reducing frailty in elderly and may contribute to healthy ageing.
Clinical practice applications:
- A comprehensive programme, encompassing not only nutrition, but also exercise, cognitive training and a focus on social and psychological wellbeing may be most effective in improving frailty and physical functioning
- Nutrition intervention, alongside other lifestyle interventions, may have benefits for nutritional status in older adults, even if this is not reflected in a change in anthropometric parameters, such as weight.
Considerations for future research:
- Studies with longer-term follow-up would help evaluate whether/for how long the benefits are sustained.
Abstract
INTRODUCTION The prevalence of frailty is increasing worldwide, emphasizing the importance of prioritizing healthy ageing. To address this, cost-effective and minimally supervised interventions are being sought. This study aimed to assess the impact of an educational program on frailty status, physical function, physical activity, sleep patterns, and nutritional status in community-dwelling older adults with at least 1 Fried's frailty criteria. METHODS A 6-month multicentre randomized controlled trial was conducted from March 2022 to February 2023 in 14 health centres located in Cadiz and Malaga, Spain. The educational intervention consisted of 4 group sessions and 6 follow-up phone calls spread over 6 months. The program focused on educating participants about frailty and its impact on health, providing guidelines for physical activity, healthy dietary habits, cognitive training, psychological well-being and social activities. A total of 163 participants, divided into control (n = 80) and educational groups (n = 83) were assessed before and after the intervention. RESULTS The results showed a significant group-time interaction in the physical function evaluated with a large effect on Short Physical Performance Battery score (η2p = 0.179, -0.1 [-1.2-1.0] points for control group vs. 1.0 [0.0-3.0] points for educational group, p < 0.001), and an effect on the 4-meter gait test ((η2p = 0.122, 0.5 [0.1-0.0] s for control group vs. -0.4 [-0.5- -0.3] s for educational group, p < 0.001), and the 5-repetition sit-to-stand test (η2p = 0.136, 1.0 [0.0-1.2] s for control group vs. -4.3 [-7.0- -2.3] for educational group, p < 0.001). Additionally, the use of accelerometers to assess physical activity, inactivity, and sleep patterns revealed a significant small effect in the number of awakenings at night ((η2p = 0.040, 1.1 [-0.5-3.4] awakenings for control group vs. 0.0 [-2.2-0.0] awakenings for educational group, p = 0.009). The findings also highlighted a significant medium effect regarding malnutrition risk, which was assessed using the Mini-Nutritional Assessment score (η2p = 0.088, -0.7 [-2.3-1.5] points for control group vs. 1.5 [-0.5-3.0] points for educational group, p < 0.001). DISCUSSION Thus, the 6-month educational program effectively improved physical function, sleep patterns, and nutritional status compared to usual healthcare attendance in community-dwelling older adults with frailty or pre-frailty. These findings underscore the potential of minimally supervised interventions in promoting a healthy lifestyle in this vulnerable population.
-
9.
Impact of probiotics on muscle mass, muscle strength and lean mass: a systematic review and meta-analysis of randomized controlled trials.
Prokopidis, K, Giannos, P, Kirwan, R, Ispoglou, T, Galli, F, Witard, OC, Triantafyllidis, KK, Kechagias, KS, Morwani-Mangnani, J, Ticinesi, A, et al
Journal of cachexia, sarcopenia and muscle. 2023;14(1):30-44
-
-
-
-
Free full text
-
Plain language summary
Sarcopenia is a progressive skeletal muscle disorder involving accelerated loss of muscle mass, strength and function. It generally occurs in older age groups but can also be seen in younger people. Multiple factors contribute to the development of the condition. Besides nutritional management strategies, probiotics have recently caught the interest of researchers. As probiotics promote metabolic building activity, aid digestion and absorption and reduce muscle breakdown by favourably managing inflammation, they present great potential for the management of sarcopenia. This systematic review and meta-analysis explored the impact of probiotic supplementation on muscle mass, total lean mass and muscle strength in human adults. The review included 24 studies, with probiotics mainly from the Bifidobacteria or Lactobacilli family. The analysis concluded that probiotic supplementation improved muscle mass in comparison to placebos. It also significantly increased overall muscle strength in 6 randomized controlled trials, which was most obvious in age groups of 50 and above. However, no changes were seen concerning total lean mass. It appeared that longer studies, of >12 weeks or more, showed better outcomes in this review. Furthermore, Bifidobacteria species seemed to exhibit more favourable effects, and the authors also noted the beneficial results were more significant in Asian populations. Further research is needed to understand more about the underlying mechanism, best probiotics strains and the specifics of different demographic groups. This article yields a concise overview of sarcopenia, the nutritional aspects of the disease and how probiotics may be beneficial in disease management, strengthened with data from the review.
Expert Review
Conflicts of interest:
None
Take Home Message:
- This was a well-conducted meta-analysis based on its methodological approach that demonstrated that Lactobacillus and Bifidobacterium probiotic supplementation may contribute to improved muscle mass in younger adults and improved muscle strength in older adults.
- Bifidobacterium probiotic supplementation was associated with enhanced muscle mass in younger adults, a potential focus for those considering probiotic supplements.
- The duration of probiotic therapy matters, with longer-term (12 weeks or more) supplementation showing improvements in muscle mass and strength..
Evidence Category:
-
X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Introduction
This systematic review and meta-analysis evaluated the effect of probiotics on muscle mass, total lean mass and muscle strength in both young and older adults.
Methods
- The search encompassed PubMed, Scopus, Web of Science, and Cochrane Library databases, from inception up to June 2022; studies included spanned a period from 2013 to June 2022.
- The study adhered to Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines and included the Risk-of-Bias tool to assess study quality.
- The study focused on changes in muscle mass, total lean mass, and muscle strength.
- Inclusion criteria: randomised controlled trials (RCTs) with adult participants (>18 years); interventions involving any probiotics, and a control group receiving either no treatment or a placebo.
Results
- 24 RCTs were included (709 participants), with studies conducted in Europe, USA, and Asia. Intervention durations: ranged from 3 weeks to 12 months.
- Participants included overweight, untrained healthy and resistance-trained individuals, and those with specific conditions like metabolic syndrome and frailty.
- Body composition assessments were conducted using bioelectrical impedance (BIA) and/or dual-energy X-ray absorptiometry (DXA).
- Probiotic strains employed in the included studies varied, with Lactobacillus the most common, followed by Bifidobacterium; some combined both. 5 of 24 studies also used additional strains.
- Dosages: ranged from 2 × 10^9 to 11.2 × 10^10 colony-forming units (CFU).
- 4 out of 24 studies used fermented food products like cheese and noodles as sources of probiotics.
- 22 RCTs measured muscle mass and total lean mass; 6 RCTs measured global muscle strength.
- Probiotic supplementation (≥12 weeks) moderately increased muscle mass, with a standardised mean difference (SMD) of 0.42. This significant effect (95% CI: 0.10–0.74, P=0.009) was observed only in younger Asian adults (<50 years) after Bifidobacterium supplementation, based on a meta-analysis of 10 studies.
- Probiotic supplementation (≥12 weeks) significantly increased global muscle strength in older adults (>50 years; SMD: 0.69, 95% CI: 0.33–1.06, P = 0.0002).
- Probiotic supplementation showed no significant impact on lean mass (SMD: -0.03, 95% CI: 0.19 – 0.13, P = 0.69).
Conclusion
Probiotic supplementation, especially Lactobacillus and Bifidobacterium may have a positive impact on muscle mass and global strength
Clinical practice applications:
- Consumption of probiotics, mainly Lactobacillus and Bifidobacterium may contribute to improved muscle strength in older individuals (>50y).
- Consumption of Bifidobacterium strains was associated with improved muscle mass in younger individuals (<50y) in Asian countries, in a low number of studies (k=2).
- Bifidobacterium breve B-3 was associated with an improvement in muscle mass in older overweight individuals, although a causal relationship was not established.
- Probiotics may enhance muscle mass or strength by enhancing protein digestion and amino acid absorption for muscle synthesis and function.
- Considering an individual’s goals, a practitioner could consider probiotic supplementation as a complementary intervention when aiming to enhance muscle mass or strength .
Considerations for future research:
- Future research could focus on pinpointing which specific probiotic strains are most effective for muscle strength or muscle mass to tailor more precise interventions.
- Most studies did not exceed 12 weeks, highlighting the need for long-term research on probiotics sustained muscle impact.
- Future research could investigate the effects of probiotics across diverse demographic groups including different ages, sexes, and ethnic backgrounds to understand the impact in different populations.
- Delving deeper into the mechanisms by which probiotics influence muscle health could lead to targeted probiotic therapies that address specific physiological pathways.
- Finally, future research could explore how probiotics can be combined with other interventions, such as exercise or nutritional modifications, to synergistically improve muscle health and function.
Abstract
Probiotics have shown potential to counteract sarcopenia, although the extent to which they can influence domains of sarcopenia such as muscle mass and strength in humans is unclear. The aim of this systematic review and meta-analysis was to explore the impact of probiotic supplementation on muscle mass, total lean mass and muscle strength in human adults. A literature search of randomized controlled trials (RCTs) was conducted through PubMed, Scopus, Web of Science and Cochrane Library from inception until June 2022. Eligible RCTs compared the effect of probiotic supplementation versus placebo on muscle and total lean mass and global muscle strength (composite score of all muscle strength outcomes) in adults (>18 years). To evaluate the differences between groups, a meta-analysis was conducted using the random effects inverse-variance model by utilizing standardized mean differences. Twenty-four studies were included in the systematic review and meta-analysis exploring the effects of probiotics on muscle mass, total lean mass and global muscle strength. Our main analysis (k = 10) revealed that muscle mass was improved following probiotics compared with placebo (SMD: 0.42, 95% CI: 0.10-0.74, I2 = 57%, P = 0.009), although no changes were revealed in relation to total lean mass (k = 12; SMD: -0.03, 95% CI: -0.19 - 0.13, I2 = 0%, P = 0.69). Interestingly, a significant increase in global muscle strength was also observed among six RCTs (SMD: 0.69, 95% CI: 0.33-1.06, I2 = 64%, P = 0.0002). Probiotic supplementation enhances both muscle mass and global muscle strength; however, no beneficial effects were observed in total lean mass. Investigating the physiological mechanisms underpinning different ageing groups and elucidating appropriate probiotic strains for optimal gains in muscle mass and strength are warranted.
-
10.
Distribution of energy intake across the day and weight loss: A systematic review and meta-analysis.
Young, IE, Poobalan, A, Steinbeck, K, O'Connor, HT, Parker, HM
Obesity reviews : an official journal of the International Association for the Study of Obesity. 2023;24(3):e13537
-
-
-
-
Free full text
-
Plain language summary
Obesity increases an individual's risk of metabolic disease, such as diabetes and cardiovascular disease, musculoskeletal disorders such as osteoarthritis, and some cancers. “Chrononutrition” relates to the timing of meals and distribution of total energy intake across the day. Evidence is building chrononutrition as a potential target in both weight loss and metabolic disease interventions. The aim of this study was to examine the impact of earlier versus later distribution of total daily energy intake on weight loss, and to evaluate the potential for utilizing altered energy distribution as a tool in weight loss interventions. This study is a systematic review and meta-analysis of nine clinical studies. Total number of participants was 485 (earlier distributed total energy intakes: n = 244, later distributed total energy intakes; n = 241). Results show that energy intakes with a focus on earlier distribution resulted in significantly greater weight loss when compared with similarly energy-restricted diets with individuals consuming a larger proportion of their total energy intake later in the day and into the evening. Authors conclude that earlier energy intakes may be a promising tool to be used in conjunction with other weight loss strategies such as energy restriction to enhance weight loss. However, further research is required to elucidate the additional positive impacts that earlier distributed total energy intakes may have on weight and metabolic health.
Expert Review
Conflicts of interest:
None
Take Home Message:
Implementing a dietary strategy where a higher proportion of energy is consumed earlier in the day may offer additional benefits to an energy restricted diet for weight loss, blood glucose, improve markers of insulin resistance, increase satiety and improve hunger management. Based on the findings, earlier distribution of energy intake may serve as an effective component of a weight loss protocol.
Evidence Category:
-
X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Background
Chrononutrition refers to the timing and distribution of total daily energy intake across the day. It has been proposed that consuming a greater proportion of total daily energy intake earlier in the day as opposed to the evening may be beneficial for weight loss and metabolic health.
Aims
This systematic review and meta-analysis aimed to assess the impact of earlier versus later distribution of total daily energy intake on weight loss.
Results
A total of 9 randomised controlled trials involving 485 participants were included in this analysis. The study durations ranged from 5-16 weeks. All of the studies included in this analysis applied energy-restricted diets to both intervention arms. The mean percentages of energy intake in 8 of the 9 studies per meal were:
- Earlier distributed intakes: breakfast: 34% ± 16%, lunch: 38% ± 7%, dinner: 20% ± 6%.
- Later distributed intakes: breakfast: 19% ± 6%, lunch: 30% ± 10%, dinner; 40% ± 11%.
One of the studies advised percentage of energy intakes as either:
- Earlier: 70% for breakfast, morning tea and lunch and 30% for afternoon tea and dinner
- Late: 55% for breakfast, morning tea and lunch and 45% for afternoon tea and dinner.
The earlier distributed energy intake groups demonstrated significantly greater weight loss when compared with later distributed energy intake groups ( Mean Difference (MD) −1.23 kg; 95% CI −2.40, −0.06, p = 0.04;
I2 = 98%).
The earlier energy intake groups also displayed lower fasting and bedtime glucose levels (fasting: −0.83 vs. −0.27 mmol/L, p = 0.001; before sleep: −1.70 vs. −0.28 mmol/L, p = 0.009).
A random-effects model demonstrated that the earlier intake groups displayed greater reductions in LDL (MD: −0.11 mmol/L; 95% CI −0.14, −0.07, p < 0.01), fasting glucose (MD: 0.15 mmol/L, 95% CI −0.23, −0.06, p < 0.001) and HOMA-IR (MD: −0.38; 95% CI −0.64, −0.11, p = 0.005).
One study reported that earlier distribution energy intake also led to a greater reduction in medications following the intervention for type 2 diabetics (31% vs. 0%, P=0.002).
Two of the studies assessed both appetite and hunger and identified that earlier distribution of energy led to improvements in their urge to eat, preoccupation with food and cravings for sweets and fats.
Clinical practice applications:
Earlier distribution of energy intake may be beneficial for:
- Weight loss
- Improve fasting insulin, HOMA-IR, fasting glucose and HbA1c
- Reducing LDL
- Improving satiety and hunger management
- Supporting the reduction of medications for individuals with type 2 diabetes
- Improving regularity of sleep and waking times
Considerations for future research:
As the included studies only ranged from 5-16 weeks, longer duration studies would be useful to identify the effect of earlier distribution of energy intake on body weight, metabolic health and appetite over a longer period of time. There was a high degree of heterogeneity between the studies and a lack of uniformity in the distributions of energy intake across the day. Further studies with more uniformity of energy distribution would be needed to identify the optimal distribution of energy across the day to improve body weight and metabolic health.
Abstract
Consuming a greater proportion of total energy intake earlier in the day rather than in the evening is proposed to positively influence weight loss and health, potentially due to greater synchronization of human body circadian rhythms. This systematic review provides an update on existing evidence regarding earlier distributed eating patterns in weight loss interventions. Using a robust search strategy in five electronic databases, nine randomized controlled trials investigating the impact of energy intake distribution on weight loss were identified. Following critical appraisal, a random-effects meta-analyses found that, in the context of an energy-reduced diet, distributing energy intake with a focus on earlier intake resulted in significantly greater weight loss (-1.23 kg; 95% CI 2.40, -0.06, p = 0.04). Improvements in HOMA-IR, fasting glucose, and LDL cholesterol were also seen. The current study provides a timely update on the evidence linking distribution of total daily energy intake and health, showing that a focus on earlier intakes can result in greater short-term weight loss compared with later intakes. Future studies are needed to elucidate the impact that earlier intakes may have on weight management and metabolic health.