-
1.
Macronutrient composition and its effect on body composition changes during weight loss therapy in patients with non-alcoholic fatty liver disease: Secondary analysis of a randomized controlled trial.
Lindqvist, C, Holmer, M, Hagström, H, Petersson, S, Tillander, V, Brismar, TB, Stål, P
Nutrition (Burbank, Los Angeles County, Calif.). 2023;110:111982
-
-
-
Free full text
Plain language summary
Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide and it is closely linked to overweight and obesity. Weight loss leads to an amelioration of NAFLD, which preferably should lead to loss of fat mass while maintaining lean body mass. The aim of this study was to examine if different diet compositions during weight loss therapy were associated with different reductions in abdominal fat mass compared with standard weight loss advice given by a physician. This study was a secondary analysis of data collected in an open-label, randomised controlled trial. The trial examined the effect of two popular weight loss diets, calorie-restricted intermittent fasting (5:2) and a calorie-restricted low-carbohydrate high-fat (LCHF) diet, compared with standard of care (SOC) on reduction in liver fat in 74 persons with NAFLD. Results show that a dietitian-led nutrition counselling treatment with an LCHF or 5:2 diet reduced weight to a higher extent than physician-supported SOC during a 12-wk treatment. Improvements in most of the variables related to body composition parameters and metabolic function were found, independent of dietary composition. Furthermore, during weight loss, visceral fat was mobilized to a greater extent than subcutaneous fat. Authors conclude that further studies are needed with a focus on the effect of diet composition on body composition changes during weight loss.
Abstract
OBJECTIVES Dietary composition may affect body composition during weight loss therapy. We tested the hypothesis of whether dietary macronutrient composition influences the reduction of total abdominal adipose tissue, subcutaneous adipose tissue (SAT), or visceral adipose tissue (VAT) during weight loss. METHODS Dietary macronutrient composition and body composition were analyzed as a secondary outcome of a randomized controlled trial of 62 participants with non-alcoholic fatty liver disease. Patients were randomly assigned to a calorie-restricted intermittent fasting (5:2), calorie-restricted low-carbohydrate high-fat (LCHF), or healthy lifestyle advice (standard-of-care) diet in a 12-wk intervention phase. Dietary intake was assessed by self-reported 3-d food diaries and by characterization of total plasma fatty acid profile. Percentage of energy intake (E%) from different macronutrients was calculated. Body composition was assessed by magnetic resonance imaging and anthropometric measurements. RESULTS The macronutrient composition differed significantly between the 5:2 (fat 36 E% and carbohydrates 43 E%) and the LCHF (fat 69 E% and carbohydrates 9 E%) groups (P < 0.001). Weight loss was similar in the 5:2 and LCHF groups (-7.2 [SD = 3.4] kg versus 8.0 [SD = 4.8] kg; P = 0.44) and significantly larger than for standard of care (-2.5 kg [SD = 2.3]; P < 0.001). The volume of total abdominal fat, adjusted for height, decreased on average by 4.7% (standard of care), 14.3% (5:2), and 17.7% (LCHF), with no significant differences between the 5:2 and LHCF groups (P = 0.32). VAT and SAT, adjusted for height, decreased on average by 17.1% and 12.7% for 5:2, respectively, and by 21.2% and 17.9% for LCHF, with no significant group differences (VAT [P = 0.16] and SAT [P = 0.10]). VAT was mobilized to a greater extent than SAT in all diets. CONCLUSIONS The 5:2 and LCHF diets had similar effects on changes in intraabdominal fat mass and anthropometrics during weight loss. This might indicate that overall weight loss is more important than diet composition to achieve changes in total abdominal adipose tissue, VAT, or SAT. The results of the present study suggest that there is a need for further studies on the effect of diet composition on body composition changes during weight loss therapy.
-
2.
Treatment of obesity and metabolic-associated fatty liver disease with a diet or orlistat: A randomized controlled trial.
Feng, X, Lin, Y, Zhuo, S, Dong, Z, Shao, C, Ye, J, Zhong, B
The American journal of clinical nutrition. 2023;117(4):691-700
-
-
-
Free full text
Plain language summary
Metabolic-associated fatty liver disease (MAFLD) is characterised by excessive lipid accumulation in hepatocytes. Weight management by the treatment to target strategy through lifestyle intervention remains the primary approach for MAFLD treatment. The aim of this study was to compare the efficacy of a conventional energy-restricted diet (the control group), orlistat, and an experimental diet in the Asian population with obesity and MAFLD. This study was a prospective, open-label, monocentric randomised controlled study. Participants (n = 118) were randomly assigned to the control (n = 39), orlistat (n = 40), or experimental diet (n = 39) groups at a 1:1:1 allocation. Results showed that: - orlistat and the experimental diet were superior to lifestyle intervention in ameliorating liver steatosis [fatty liver]. - the experimental diet had an advantage over lifestyle intervention when patients adhered to the diet. - orlistat was superior to the experimental diet and lifestyle modifications in decreasing liver fat content. Authors conclude that more multicentre, large-scale, prospective studies are needed to verify the long-term efficacy and safety of the experimental diet and orlistat treatment in subjects with MAFLD.
Abstract
BACKGROUND Losing weight by lifestyle interventions is the first-line treatment for metabolic-associated fatty liver disease (MAFLD) but is limited by low compliance. OBJECTIVES This study aimed to compare the effects of orlistat or an experimental high-protein/lower-carbohydrate diet with a control diet in Asian patients with obesity and MAFLD. METHODS A total of 118 Asian patients with obesity and MAFLD confirmed with MRI-based proton density fat fraction with Dixon sequence were enrolled and allocated to the control group, the orlistat group, or the experimental diet group for 24 wk. The primary endpoint was the relative change in liver fat content (LFC) assessed by MRI-based proton density fat fraction. RESULTS A total of 118 subjects with obesity and MAFLD were randomly assigned to the control group (n = 39), the orlistat group (n = 40), or the experimental diet group (n = 39). All 3 groups demonstrated improvement in liver steatosis at wk 24. The absolute decrease in LFC in the orlistat group was 9.1% and 5.4% in the experimental diet group, both significantly higher than that in the control group (P < 0.05). The relative reduction in LFC was 30.2% in the experimental diet group, which was significantly higher than the 12.2% observed in the control group (P = 0.01). CONCLUSIONS Orlistat and the experimental diet group reduced liver steatosis compared to the control group. This trial was registered at Chinese Clinical Trial Registry (ChiCTR-1900027172). http://www.chictr.org.cn.
-
3.
An Energy-Reduced Mediterranean Diet, Physical Activity, and Body Composition: An Interim Subgroup Analysis of the PREDIMED-Plus Randomized Clinical Trial.
Konieczna, J, Ruiz-Canela, M, Galmes-Panades, AM, Abete, I, Babio, N, Fiol, M, Martín-Sánchez, V, Estruch, R, Vidal, J, Buil-Cosiales, P, et al
JAMA network open. 2023;6(10):e2337994
-
-
-
-
Free full text
-
Plain language summary
The Mediterranean diet (MedDiet), which focuses on whole grains, lean meat, fruits, vegetables, and low amounts of minimally processed foods has been shown in previous research to improve body composition and decrease fat storage around the middle. This randomised control trial of 1556 older adults aimed to determine the effects of combining a 30% lower energy version of the MedDiet in combination with physical exercise on body composition. After 3 years, the results showed that compared to a normal MedDiet without exercise, the lower energy version in combination with exercise improved body composition by decreasing total fat, and the fat stored around the organs and increasing muscle mass. However, benefits were more pronounced after 1 year and decreased slightly at 3 years. It was concluded that a low energy MedDiet in combination with physical activity may be able to improve the body composition of overweight and older adults with obesity. This study could be used by healthcare professionals to recommend a low energy MedDiet to older adults to promote weight loss, whilst attenuating muscle loss associated with ageing.
Expert Review
Conflicts of interest:
None
Take Home Message:
- The addition of exercise to an energy-reduced diet, which focuses on whole grains, healthy fats, lean protein, and fruits and vegetables can emphasise positive effects on body composition in older adults.
- However, there is a loss of lean mass associated with this type of diet (contrary to author conclusions) and measures should be taken to monitor and increase protein intake to prevent or limit this loss.
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 study aimed to determine the long-term effects of an energy reduced MedDiet in combination with physical activity on body composition.
Methods
- This is a predetermined 3-year interim analysis of a 6-year single-blind, randomised control trial of 1556 individuals aged 55-75 who are overweight or obese with metabolic syndrome.
- 760 individuals on 30% energy reduced MedDiet with limited processed foods, plus 45 minutes walking 6 days per week and behavioural and motivational support. [Intervention group]
- 761 on standard MedDiet without physical activity. [Control]
Results
Within group comparisons showed that individuals in the intervention group lost (P value represents baseline vs year 3):
- Total fat mass percentage (1-year vs baseline, −1.14%; 95% CI, −1.32% to −0.96%; 3-year vs baseline, −0.52%; 95% CI, −0.71% to −0.33% P=<0.001)
- Absolute visceral fat (1-year vs baseline, −154 g; 95% CI, −191 to −116 g; 3-year vs baseline, −75.1 g, 95% CI, −115 to −35.3 g P=<0.001)
- Absolute total fat after 1 year (mean change at 1 year vs baseline, −1677 g; 95% CI, −1930 to −1424 g) but regained some at year 3 (mean change at 3 years vs baseline, −1018 g; 95% CI, −1280 to −756 g P=<0.001)
- Absolute lean mass (mean change at 1 year vs baseline −300 g; 95% CI, −439 to −162 g) with further losses at year 3 (−626 g; 95% CI, −770 to −483 g P=0.001).
Within group comparisons also showed significantly increased:
- Total lean mass percentage, which was greater at year 1 than year 3 (1-year vs baseline, 1.07%; 95%CI, 0.90%-1.25%; 3-year vs baseline, 0.47%; 95% CI, 0.29%-0.65% P=<0.001).
As a result of total fat loss and some lean mass in the intervention group, the lean:fat mass ratio improved and was unchanged in the control group (between group differences (P=<0.001).
Compared to women, men may find the MedDiet + exercise more beneficial as it was shown that body composition changes were slightly more pronounced in men.
Conclusion
An energy-reduced MedDiet plus exercise emphasised positive changes to body composition compared to standard MedDiet in older adults who are overweight or have obesity.
Clinical practice applications:
- The recommendation of a reduced energy MedDiet in combination with physical activity to older people who are overweight or obese may improve body composition.
- Although lean mass loss slowed between years 1 and 3, other practices should be employed to attenuate the loss of lean mass associated with an energy-reduced MedDiet and ageing.
Considerations for future research:
- The research has not yet concluded but when it does, it will address the incidence of cardiovascular disease along with body composition changes.
- It will also look at long-term effects of the diet to determine longevity.
- Future research could focus on how to limit lean mass loss through the possibility of changing the type of exercise that accompanies the MedDiet.
Abstract
IMPORTANCE Strategies targeting body composition may help prevent chronic diseases in persons with excess weight, but randomized clinical trials evaluating lifestyle interventions have rarely reported effects on directly quantified body composition. OBJECTIVE To evaluate the effects of a lifestyle weight-loss intervention on changes in overall and regional body composition. DESIGN, SETTING, AND PARTICIPANTS The ongoing Prevención con Dieta Mediterránea-Plus (PREDIMED-Plus) randomized clinical trial is designed to test the effect of the intervention on cardiovascular disease prevention after 8 years of follow-up. The trial is being conducted in 23 Spanish research centers and includes men and women (age 55-75 years) with body mass index between 27 and 40 and metabolic syndrome. The trial reported herein is an interim subgroup analysis of the intermediate outcome body composition after 3-year follow-up, and data analysis was conducted from February 1 to November 30, 2022. Of 6874 total PREDIMED-Plus participants, a subsample of 1521 individuals, coming from centers with access to a dual energy x-ray absorptiometry device, underwent body composition measurements at 3 time points. INTERVENTION Participants were randomly allocated to a multifactorial intervention based on an energy-reduced Mediterranean diet (MedDiet) and increased physical activity (PA) or to a control group based on usual care, with advice to follow an ad libitum MedDiet, but no physical activity promotion. MAIN OUTCOMES AND MEASURES The outcomes (continuous) were 3-year changes in total fat and lean mass (expressed as percentages of body mass) and visceral fat (in grams), tested using multivariable linear mixed-effects models. Clinical relevance of changes in body components (dichotomous) was assessed based on 5% or more improvements in baseline values, using logistic regression. Main analyses were performed in the evaluable population (completers only) and in sensitivity analyses, multiple imputation was performed to include data of participants lost to follow-up (intention-to-treat analyses). RESULTS A total of 1521 individuals were included (mean [SD] age, 65.3 [5.0] years; 52.1% men). In comparison with the control group (n=761), participants in the intervention arm (n=760) showed greater reductions in the percentage of total fat (between group differences after 1-year, -0.94% [95% CI, -1.19 to -0.69]; 3 years, -0.38% [95% CI, -0.64 to -0.12] and visceral fat storage after 1 year, -126 g [95% CI, -179 to -73.3 g]; 3 years, -70.4 g [95% CI, -126 to -15.2 g] and greater increases in the percentage of total lean mass at 1 year, 0.88% [95% CI, 0.63%-1.12%]; 3-years 0.34% [95% CI, 0.09%-0.60%]). The intervention group was more likely to show improvements of 5% or more in baseline body components (absolute risk reduction after 1 year, 13% for total fat mass, 11% for total lean mass, and 14% for visceral fat mass; after 3-years: 6% for total fat mass, 6% for total lean mass, and 8% for visceral fat mass). The number of participants needed to treat was between 12 and 17 to attain at least 1 individual with possibly clinically meaningful improvements in body composition. CONCLUSIONS AND RELEVANCE The findings of this trial suggest a weight-loss lifestyle intervention based on an energy-reduced MedDiet and physical activity significantly reduced total and visceral fat and attenuated age-related losses of lean mass in older adults with overweight or obesity and metabolic syndrome. Continued follow-up is warranted to confirm the long-term consequences of these changes on cardiovascular clinical end points. TRIAL REGISTRATION isrctn.org Identifier: ISRCTN89898870.
-
4.
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.
-
5.
Trial of the MIND Diet for Prevention of Cognitive Decline in Older Persons.
Barnes, LL, Dhana, K, Liu, X, Carey, VJ, Ventrelle, J, Johnson, K, Hollings, CS, Bishop, L, Laranjo, N, Stubbs, BJ, et al
The New England journal of medicine. 2023;389(7):602-611
-
-
-
Free full text
-
Plain language summary
Lifestyle interventions targeting diet are a possible approach that could affect public health. Most clinical trials have investigated comprehensive diets, in contrast to dietary manipulation of single foods or nutrients. The aim of this study was to evaluate the effects of a 3-year dietary intervention on cognitive decline and brain-imaging markers of dementia and Alzheimer’s disease in older, cognitively unimpaired adults at risk for dementia because of family history. This study was a 3-year, two-site, randomised, controlled trial. The participants were randomly assigned to follow the MIND diet with mild caloric restriction for weight loss or their usual diet with the same mild caloric restriction for weight loss (control diet). Participants were randomly assigned in a 1:1 ratio. Results showed that the participants who followed the MIND diet had small improvements in a global measure of cognition that were similar to those who followed a control diet with mild caloric restriction. Authors concluded that brain health, cognitive function and brain imaging outcomes (after 3 years) did not differ significantly between participants who followed the MIND diet and those who followed a control diet with a mild caloric restriction.
Abstract
BACKGROUND Findings from observational studies suggest that dietary patterns may offer protective benefits against cognitive decline, but data from clinical trials are limited. The Mediterranean-DASH Intervention for Neurodegenerative Delay, known as the MIND diet, is a hybrid of the Mediterranean diet and the DASH (Dietary Approaches to Stop Hypertension) diet, with modifications to include foods that have been putatively associated with a decreased risk of dementia. METHODS We performed a two-site, randomized, controlled trial involving older adults without cognitive impairment but with a family history of dementia, a body-mass index (the weight in kilograms divided by the square of the height in meters) greater than 25, and a suboptimal diet, as determined by means of a 14-item questionnaire, to test the cognitive effects of the MIND diet with mild caloric restriction as compared with a control diet with mild caloric restriction. We assigned the participants in a 1:1 ratio to follow the intervention or the control diet for 3 years. All the participants received counseling regarding adherence to their assigned diet plus support to promote weight loss. The primary end point was the change from baseline in a global cognition score and four cognitive domain scores, all of which were derived from a 12-test battery. The raw scores from each test were converted to z scores, which were averaged across all tests to create the global cognition score and across component tests to create the four domain scores; higher scores indicate better cognitive performance. The secondary outcome was the change from baseline in magnetic resonance imaging (MRI)-derived measures of brain characteristics in a nonrandom sample of participants. RESULTS A total of 1929 persons underwent screening, and 604 were enrolled; 301 were assigned to the MIND-diet group and 303 to the control-diet group. The trial was completed by 93.4% of the participants. From baseline to year 3, improvements in global cognition scores were observed in both groups, with increases of 0.205 standardized units in the MIND-diet group and 0.170 standardized units in the control-diet group (mean difference, 0.035 standardized units; 95% confidence interval, -0.022 to 0.092; P = 0.23). Changes in white-matter hyperintensities, hippocampal volumes, and total gray- and white-matter volumes on MRI were similar in the two groups. CONCLUSIONS Among cognitively unimpaired participants with a family history of dementia, changes in cognition and brain MRI outcomes from baseline to year 3 did not differ significantly between those who followed the MIND diet and those who followed the control diet with mild caloric restriction. (Funded by the National Institute on Aging; ClinicalTrials.gov number, NCT02817074.).
-
6.
Association between Mediterranean Diet and Fatty Liver in Women with Overweight and Obesity.
Leone, A, Bertoli, S, Bedogni, G, Vignati, L, Pellizzari, M, Battezzati, A
Nutrients. 2022;14(18)
-
-
-
Free full text
Plain language summary
Non-alcoholic fatty liver disease (NAFLD) is a condition resulting from excessive lipid accumulation in the liver in individuals with low alcohol consumption. Obesity is an established risk factor for the development of NAFLD, and 50% to 75% of people with obesity also have NAFLD. The aim of this study was to evaluate the association between Mediterranean diet and non-invasive indices of fatty liver in a large sample of women with overweight and obesity. This study is a cross-sectional study of 2967 consecutive women with overweight and obesity. Results show that higher adherence to the Mediterranean diet was associated with lower indices of fatty liver in women with overweight and obesity (particularly obese women than in women who are overweight). Authors conclude that women with obesity, especially during the premenopausal period, may benefit more from following a Mediterranean-style diet.
Abstract
Obesity is a risk factor for NAFLD. However, not all people with obesity have an excessive intrahepatic fat content. Adherence to a high-quality dietary pattern may also promote liver health in obesity. A cross-sectional study of 2967 women with overweight and obesity was carried out to assess the association between a Mediterranean diet and fatty liver. All women underwent clinical examination, anthropometric measurements, blood sampling, ultrasound measurements of abdominal visceral and subcutaneous fat, and assessment of adherence to the Mediterranean diet using the 14-item MEDAS questionnaire. Fatty liver index (FLI), NAFLD fatty liver steatosis (NAFLD-FLS) and hepatic steatosis index (HSI) were calculated. In women with obesity, the MEDAS score was inversely associated with FLI (β = -0.60, 95% CI: -1.04, -0.16, p = 0.008), NAFLD-FLS (β = -0.092, 95% CI: -0.134, -0.049, p < 0.001) and HSI (β = -0.17, 95% CI: -0.30, -0.04, p = 0.011). Stronger associations were observed in premenopausal women with obesity. Mediterranean diet was inversely associated with NAFLD-FLS in women with overweight, independently of menopausal status. In conclusion, Mediterranean diet is associated with a better liver status in women with overweight and obesity. This may have a public health impact and be useful in drafting nutritional guidelines for NAFLD.
-
7.
Mediterranean Style Dietary Pattern with High Intensity Interval Training in Men with Prostate Cancer Treated with Androgen Deprivation Therapy: A Pilot Randomised Control Trial.
Baguley, BJ, Adlard, K, Jenkins, D, Wright, ORL, Skinner, TL
International journal of environmental research and public health. 2022;19(9)
-
-
-
Free full text
Plain language summary
The use of androgen deprivation therapy (ADT) has coincided with improvements in disease control and improved overall survivorship in many men treated for prostate cancer. Exercise and nutrition interventions during and/or after ADT are strongly recommended to mitigate or improve body composition and reduce cardiometabolic side effects. The aim of this study was to examine the combined effects of a Mediterranean diet (MED-diet) and high intensity interval training (HIIT) on cardiorespiratory fitness, body composition and quality of life, compared to usual care, in men with prostate cancer treated with ADT. This study is a two-arm randomised controlled trial. Participants (n = 23) were randomly allocated to either an intervention or usual care group in a 1:1 ratio. Results show that for men with prostate cancer undergoing ADT, a MED-diet with HIIT compared to usual care at 20 weeks (i) significantly improved cardiorespiratory fitness relative; (ii) reduced body weight; (iii) maintained lean body mass despite achieving weight loss; (iv) significantly improved vitality and mental health composite, and clinical improvements were seen in prostate-cancer specific quality of life and cancer-related fatigue. Authors conclude that future larger-scale trials examining the MED-diet with HIIT on cardiorespiratory fitness, body composition and quality of life would help to extend the findings of their study.
Abstract
Background: Androgen deprivation therapy (ADT) in prostate cancer has been shown to deteriorate body composition (reduced lean mass and increased body and fat mass) and increase the risk of cardiovascular morbidity. The Mediterranean style dietary pattern (MED-diet) and high intensity interval training (HIIT) may synergistically alleviate these side effects and improve quality of life in men treated with ADT. Methods: Twenty-three men (65.9 ± 7.8 years; body mass index: 29.6 ± 2.7 kg/m2; ADT duration: 33.8 ± 35.6 months) receiving ADT for ≥3 months were randomly assigned (1:1) to 20 weeks of usual care or the MED-diet (10 nutrition consults) with HIIT (4 × 4 min 85−95% heart rate peak, 3× week, starting at 12 weeks). Results: The MED-diet with HIIT significantly improved cardiorespiratory fitness (+4.9 mL·kg−1·min, p < 0.001), and body mass (−3.3 kg, p < 0.001) compared to the usual care group at 20 weeks. Clinically meaningful (≥3 points) improvements were seen in quality of life and cancer-related fatigue after 20 weeks. Conclusions: The MED-diet with HIIT increased cardiorespiratory fitness and reduced body weight in men with prostate cancer treated with ADT. Larger trials determining whether the MED-diet with HIIT translates to cardiovascular benefits are warranted.
-
8.
The effect of high-polyphenol Mediterranean diet on visceral adiposity: the DIRECT PLUS randomized controlled trial.
Zelicha, H, Kloting, N, Kaplan, A, Yaskolka Meir, A, Rinott, E, Tsaban, G, Chassidim, Y, Bluher, M, Ceglarek, U, Isermann, B, et al
BMC medicine. 2022;20(1):327
-
-
-
-
Free full text
Plain language summary
Visceral adipose tissue (VAT) accumulation is one of the main key factors that differentiate between metabolic healthy and unhealthy obese individuals. VAT is closely related to the development of multiple cardiovascular risk factors. The Mediterranean (MED) diet, high in polyphenol content and rich in plant food sources, was shown to have an enhanced effect on VAT reduction in combination with physical activity (PA), regardless of weight loss The aim of this study was to assess the effect of the MED diet, further enriched with polyphenols, and lower in red and processed meat (“green-MED diet”) on visceral adiposity in the 18-month Dietary Intervention Randomized Controlled Trial-Polyphenols, Unprocessed trial. This study is a randomised controlled trial. Participants were randomly assigned to one of three intervention groups (1:1:1 ratio): healthy dietary guidelines, MED diet, or green-MED diet, all included PA recommendations, with a free gym membership and educational sessions promoting moderate-intensity PA. Results show that participants following the green-MED diet achieved more than twice the degree of VAT reduction compared to those following the MED diet, despite similar weight loss. In fact, VAT loss was specifically related to lower red meat intake and increased walnuts, green tea, Wolfa globosa, and dietary fibre (this was reflected by higher plasma polyphenol and serum folate levels). Authors conclude that a green-MED diet enriched with polyphenols and decreased red meat consumption might serve as an improved version of the MED diet for targeted VAT reduction.
Expert Review
Conflicts of interest:
None
Take Home Message:
- The positive health effects of the traditional MED diet, moderately high in PUFAs and MUFAs and low in red meat, are well-established
- Higher levels of total plasma polyphenol and serum folate may reflect higher consumption of “green” dietary components, which were significantly associated with greater VAT loss
- The green-MED diet, richer in dietary polyphenols and green plant-based proteins and lower in red meat, might be a more effective strategy for VAT loss than the traditional healthy MED diet, achieving more than twice the degree of VAT reduction, despite similar weight loss.
- VAT loss was specifically related to lower red meat intake and increased walnuts, green tea, Wolffia globosa, and dietary fibre and was reflected by higher plasma polyphenol and serum folate levels.
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:
A mediterranean (MED) diet is a rich source of polyphenols, which benefit adiposity by several mechanisms. Visceral adipose tissue (VAT) accumulation is one of the main factors that differentiate between metabolic healthy and unhealthy obese individuals.
In this Dietary Intervention Randomised Controlled Trial PoLyphenols UnproceSsed (DIRECT‐ PLUS) weight‐loss trial, 294 participants were randomised to: (A) healthy dietary guidelines (HDG), (B) MED, or (C) green‐MED diets, all combined with physical activity. The study duration was 18‐months.
This study explored the effect of the green‐MED diet, twice fortified in dietary polyphenols and lower in red/processed meat, on visceral adipose tissue (VAT) and used magnetic resonance imaging (MRI) to quantify the abdominal adipose tissues.
Both isocaloric (with the same calorific value) MED groups consumed 28 g/day of walnuts (+ 440 mg/day polyphenols). The green‐MED group further consumed green tea (3–4 cups/day) and Wolffia globosa (duckweed strain) plant green shake (100 g frozen cubes/day) (+ 800mg/day polyphenols) and reduced red meat intake.
The mean weight loss (HDG: −0.4% (5.0), MED: −2.7% (5.6), green-MED: −3.9% (6.5)) and WC loss (HDG: −3.6% (5.1), MED: −4.7% (5.0), green-MED: −5.7%(5.7)) after 18 months were similar between the two MED diets (p > 0.05 for all) and higher as compared to the HDG (weight: HDG vs. MED: p = 0.02; HDG vs. green+MED: p < 0.001; WC: HDG vs. MED: p = 0.33, HDG vs. green+MED: p = 0.02).
All three abdominal fat depots decreased over 18 months of intervention (p < 0.05 vs. baseline for all). The green-MED group achieved a greater reduction in VAT than the other intervention groups (HDG: −4.2% (22.5), MED: −6.0%(31.3), green-MED: −14.1%(27.7); p < 0.05 green-MED vs. MED or vs. HDG groups). These differences in VAT loss across the groups remained significant after adjusting for age, sex, and 18-month WC change (green-MED vs. MED p = 0.023; green-MED vs. HDG p = 0.002) (Fig. 1)
Limitations of the study included a low proportion of women, and different VAT proportions at baseline across groups limit the generalisability of findings to women.
The authors of the study did not identify the exact components responsible for the dietary effects when they compared dietary regimens and not specific nutrients.
Adherence was by a validated, self-reported dietary intake assessment tool, which the authors acknowledge is subject to error
Strengths of the study included the relatively large sample size, high retention rate, and use of 3-T MRI measurements (considered one of the gold standards tools for the quantification of specific fat depots
Clinical practice applications:
- This trial shows that, when combined with a Mediterranean diet, higher dietary consumption of green tea, walnuts, and dietary fibre and reduced red meat consumption were significantly associated with greater %VAT loss
- The authors observed a significant synergistic interaction effect between decreased red meat consumption and increased serum folate on VAT loss
- A reduction in VAT accumulation, known as a key risk factor in CVD development, may reduce metabolic complications, improve the lipid profile, and decrease cardiometabolic risk.
Considerations for future research:
- Future studies are needed to explore the exact mechanisms of specific polyphenol-rich foods on visceral adiposity.
- Future studies could explore whether the results are replicable in both male and female participants, as this sample was largely male.
Abstract
BACKGROUND Mediterranean (MED) diet is a rich source of polyphenols, which benefit adiposity by several mechanisms. We explored the effect of the green-MED diet, twice fortified in dietary polyphenols and lower in red/processed meat, on visceral adipose tissue (VAT). METHODS In the 18-month Dietary Intervention Randomized Controlled Trial PoLyphenols UnproceSsed (DIRECT-PLUS) weight-loss trial, 294 participants were randomized to (A) healthy dietary guidelines (HDG), (B) MED, or (C) green-MED diets, all combined with physical activity. Both isocaloric MED groups consumed 28 g/day of walnuts (+ 440 mg/day polyphenols). The green-MED group further consumed green tea (3-4 cups/day) and Wolffia globosa (duckweed strain) plant green shake (100 g frozen cubes/day) (+ 800mg/day polyphenols) and reduced red meat intake. We used magnetic resonance imaging (MRI) to quantify the abdominal adipose tissues. RESULTS Participants (age = 51 years; 88% men; body mass index = 31.2 kg/m2; 29% VAT) had an 89.8% retention rate and 79.3% completed eligible MRIs. While both MED diets reached similar moderate weight (MED: - 2.7%, green-MED: - 3.9%) and waist circumference (MED: - 4.7%, green-MED: - 5.7%) loss, the green-MED dieters doubled the VAT loss (HDG: - 4.2%, MED: - 6.0%, green-MED: - 14.1%; p < 0.05, independent of age, sex, waist circumference, or weight loss). Higher dietary consumption of green tea, walnuts, and Wolffia globosa; lower red meat intake; higher total plasma polyphenols (mainly hippuric acid), and elevated urine urolithin A polyphenol were significantly related to greater VAT loss (p < 0.05, multivariate models). CONCLUSIONS A green-MED diet, enriched with plant-based polyphenols and lower in red/processed meat, may be a potent intervention to promote visceral adiposity regression. TRIAL REGISTRATION ClinicalTrials.gov , NCT03020186.
-
9.
Mediterranean and Western diet effects on Alzheimer's disease biomarkers, cerebral perfusion, and cognition in mid-life: A randomized trial.
Hoscheidt, S, Sanderlin, AH, Baker, LD, Jung, Y, Lockhart, S, Kellar, D, Whitlow, CT, Hanson, AJ, Friedman, S, Register, T, et al
Alzheimer's & dementia : the journal of the Alzheimer's Association. 2022;18(3):457-468
-
-
-
-
Free full text
-
Plain language summary
There is a current understanding that Alzheimer’s disease (AD) development is related to a high intake of saturated fat and simple carbohydrates, which are found in abundance in the so-called Western Diet (WD). In contrast the consumption of low saturated fat and simple carbohydrates characteristic of the Mediterranean Diet (MD), has been associated with a reduced risk for the development of AD. This study aimed to look at the association of the MD and WD with AD in a more robust way using the randomised control method in 84 individuals both with and without mild memory impairment. The results showed that depending on whether an individual has mild brain impairment determines their response to the MD or WD after 4 weeks. In those without brain impairment the adoption of the WD resulted in a shift towards increasing the risk for AD development and the reverse following the MD. Whereas in those with brain impairment, the adoption of the WD was protective against the development of AD and the MD moved individuals towards worse disease outcomes. It was concluded that diet can be of importance in the prevention or progression of AD and that further studies are required to determine the possible mechanisms through which these two diets can act differentially. This study could be used by health care professionals to understand that diet can have a large impact on AD.
Expert Review
Conflicts of interest:
None
Take Home Message:
- A Med-diet may be beneficial for supporting brain health, cognitive function. metabolic health and reduce the risk of an AD pathology in middle-aged adults with normal cognitive function
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
Epidemiological studies have associated a Western diet (West-diet) with an increased risk of Alzheimer’s disease (AD) and other dementias. This study aimed to examine the impact of a Mediterranean-diet (Med-diet) versus a West-diet on AD pathology, cognition, vascular function and metabolic markers in middle aged adults with normal cognitive (NC) function compared to adults with mild cognitive impairment (MCI).
Methods
N=41 NC adult females completed the Med-diet and N=43 adult females with MCI completed the West-diet arm of this study. The average age of the participants was 56y. All participants received isocaloric diets which were either high or low in saturated fat, sodium and glycaemic index (GI) for 4 weeks. Statistical analyses were conducted per dietary arm as well as per cognitive function (NC vs MCI).
Results
- NC Participants were found to have decreased cerebro-spinal fluid (CSF) biomarkers (p=.026) following the Med-diet and increased levels following the West-diet. Whereas, cerebral perfusion increased following the med-diet and decreased after the West-diet (p=.003). These results indicate a reduced AD risk. The MCI group showed no changes to CSF or cerebral perfusion for either dietary group.
- Cognition tended to improve for the NC Med-diet and remain the same for the NC West-diet group. No changes were found for the MCI groups.
- Total cholesterol levels were increased following the West-diet and decreased following the Med-diet for both groups (p=0.0001).
- Glucose and HbA1C were unchanged in the NC group following the Med-diet, increased for the West-diet (p=.049) and decreased for the MCI group (p=<.001). whereas fasting insulin was increased in the NC Med-diet group and decreased in the MCI Med-diet (p=.0.12) and West diet groups.
Conclusion
The results of this study found that diet may modulate AD pathology, cognitive and metabolic function in middle-aged adults. A West-like diet may increase risk of AD through its effects on impairing cognitive function, reducing cerebral infusion and negatively influencing metabolic health in NC adults. Conversely, A Med-diet may promote brain function and metabolic health. However, surprisingly, in this study the results were reversed for MCI middle aged adults, the results showed improvement in metabolic and cerebrospinal fluid biomarkers for the West-diet. These results require further confirmation.
No conflicts of interest were declared.
Clinical practice applications:
- A Med-diet may be beneficial for supporting brain health, cognitive function, metabolic health and reducing the risk of an AD pathology in middle-aged adults with normal cognitive function but not for those with MCI.
Considerations for future research:
The authors acknowledged several limitations to this study.
- These results require further confirmation through longer and larger studies, particularly the surprising finding that a West-diet may confer beneficial effects on metabolic and brain health for middle-aged adults with MCI.
Abstract
INTRODUCTION Mid-life dietary patterns are associated with Alzheimer's disease (AD) risk, although few controlled trials have been conducted. METHODS Eighty-seven participants (age range: 45 to 65) with normal cognition (NC, n = 56) or mild cognitive impairment (MCI, n = 31) received isocaloric diets high or low in saturated fat, glycemic index, and sodium (Western-like/West-diet vs. Mediterranean-like/Med-diet) for 4 weeks. Diet effects on cerebrospinal fluid (CSF) biomarkers, cognition, and cerebral perfusion were assessed to determine whether responses differed by cognitive status. RESULTS CSF amyloid beta (Aβ)42/40 ratios increased following the Med-diet, and decreased after West-diet for NC adults, whereas the MCI group showed the reverse pattern. For the MCI group, the West-diet reduced and the Med-diet increased total tau (t-tau), whereas CSF Aβ42 /t-tau ratios increased following the West-diet and decreased following the Med-diet. For NC participants, the Med-diet increased and the West-diet decreased cerebral perfusion. DISCUSSION Diet response during middle age may highlight early pathophysiological processes that increase AD risk.
-
10.
Lifestyle factors and visceral adipose tissue: Results from the PREDIMED-PLUS study.
Galmes-Panades, AM, Konieczna, J, Abete, I, Colom, A, Rosique-Esteban, N, Zulet, MA, Vázquez, Z, Estruch, R, Vidal, J, Toledo, E, et al
PloS one. 2019;14(1):e0210726
-
-
-
Free full text
Plain language summary
Excess visceral adipose tissue (VAT, abdominal fat) is a risk factor for developing cardiovascular disease, type 2 diabetes mellitus and all cause mortality. Lifestyle factors, including diet and physical activity, are associated with VAT. This cross-sectional study evaluated the association between different levels of physical activity (PA), adherence to an energy-restricted Mediterranean diet and sedentary lifestyle with VAT in older people with overweight/obesity and metabolic syndrome. Data were taken from an ongoing randomised study evaluating the effect of a weight loss programme based on an energy-restricted Mediterranean diet, promotion of physical activity and behavioural support compared to usual care consisting of advice on an energy-unrestricted Mediterranean diet only. Total and moderate-to-vigorous physical activity and muscle strength were inversely, and sedentary behaviour was positively associated with VAT. There was no statistically significant association between VAT and light exercise, adherence to the energy-reduced Mediterranean diet and watching TV.
Abstract
BACKGROUND Visceral adipose tissue (VAT) is a strong predictor of cardiometabolic health, and lifestyle factors may have a positive influence on VAT depot. This study aimed to assess the cross-sectional associations between baseline levels of physical activity (PA), sedentary behaviours (SB) and adherence to the Mediterranean diet (MedDiet) with VAT depot in older individuals with overweight/obesity and metabolic syndrome. METHODS Baseline data of the PREDIMED-Plus study including a sample of 1,231 Caucasian men and women aged 55-75 years were used. Levels of leisure-time PA (total, light, and moderate-to-vigorous, in METs·min/day) and SB (total and TV-viewing, in h/day) were evaluated using validated questionnaires. Adherence to the MedDiet was evaluated using a 17-item energy-restricted MedDiet (erMedDiet) screener. The chair-stand test was used to estimate the muscle strength. VAT depot was assessed with DXA-CoreScan. Multivariable adjusted linear regression models were used to evaluate the association between lifestyle factors and VAT. For the statistics we had used multiadjusted linear regression models. RESULTS Total leisure-time PA (100 METs·min/day: β -24.3g, -36.7;-11.9g), moderate-to-vigorous PA (β -27.8g, 95% CI -40.8;-14.8g), chair-stand test (repeat: β -11.5g, 95% CI -20.1;-2.93g) were inversely associated, and total SB (h/day: β 38.2g, 95% CI 14.7;61.7) positively associated with VAT. Light PA, TV-viewing time and adherence to an erMedDiet were not significantly associated with VAT. CONCLUSIONS In older adults with overweigh/obesity and metabolic syndrome, greater PA, muscle strength, and lower total SB were associated with less VAT depot. In this study, adherence to an erMedDiet was not associated with lower VAT.