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Predictors of racial differences in weight loss: the PROPEL trial.
Newton, RL, Zhang, D, Johnson, WD, Martin, CK, Apolzan, JW, Denstel, KD, Brantley, PJ, Davis, TC, Arnold, C, Sarpong, DF, et al
Obesity (Silver Spring, Md.). 2024;(3):476-485
Abstract
OBJECTIVE Studies have consistently shown that African American individuals lose less weight in response to behavioral interventions, but the mechanisms leading to this result have been understudied. METHODS Data were derived from the PROmoting Successful Weight Loss in Primary CarE in Louisiana (PROPEL) study, which was a cluster-randomized, two-arm trial conducted in primary care clinics. In the PROPEL trial, African American individuals lost less weight compared with patients who belonged to other racial groups after 24 months. In the current study, counterfactual mediation analyses among 445 patients in the intervention arm of PROPEL were used to determine which variables mediated the relationship between race and weight loss. The mediators included treatment engagement, psychosocial, and lifestyle factors. RESULTS At 6 months, daily weighing mediated 33% (p = 0.008) of the racial differences in weight loss. At 24 months, session attendance and daily weighing mediated 35% (p = 0.027) and 66% (p = 0.005) of the racial differences in weight loss, respectively. None of the psychosocial or lifestyle variables mediated the race-weight loss association. CONCLUSIONS Strategies specifically targeting engagement, such as improving session attendance and self-weighing behaviors, among African American individuals are needed to support more equitable weight losses over extended time periods.
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Exercise-induced Changes in Central Adiposity During an RCT: Effect of Exercise Dose and Associations With Compensation.
Dorling, JL, Apolzan, JW, Johannsen, NM, Thomas, DM, Höchsmann, C, Hsia, DS, Martin, CK
The Journal of clinical endocrinology and metabolism. 2024;(3):e997-e1005
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CONTEXT Exercise can decrease central adiposity, but the effect of exercise dose and the relationship between central adiposity and exercise-induced compensation is unclear. OBJECTIVE Test the effect of exercise dose on central adiposity change and the association between central adiposity and exercise-induced weight compensation. METHODS In this ancillary analysis of a 6-month randomized controlled trial, 170 participants with overweight or obesity (mean ± SD body mass index: 31.5 ± 4.7 kg/m2) were randomized to a control group or exercise groups that reflected exercise recommendations for health (8 kcal/kg/week [KKW]) or weight loss and weight maintenance (20 KKW). Waist circumference was measured, and dual-energy X-ray absorptiometry assessed central adiposity. Predicted weight change was estimated and weight compensation (weight change - predicted weight change) was calculated. RESULTS Between-group change in waist circumference (control: .0 cm [95% CI, -1.0 to 1.0], 8 KKW: -.7 cm [95% CI, -1.7 to .4], 20 KKW: -1.3 cm [95% CI, -2.4 to -.2]) and visceral adipose tissue (VAT; control: -.02 kg [95% CI, -.07 to .04], 8 KKW: -.01 kg [95% CI, -.07 to .04], 20 KKW: -.04 kg [95% CI, -.10 to .02]) was similar (P ≥ .23). Most exercisers (82.6%) compensated (weight loss less than expected). Exercisers who compensated exhibited a 2.5-cm (95% CI, .8 to 4.2) and .23-kg (95% CI, .14 to .31) increase in waist circumference and VAT, respectively, vs those who did not (P < .01). Desire to eat predicted VAT change during exercise (β = .21; P = .03). CONCLUSION In the presence of significant weight compensation, exercise at doses recommended for health and weight loss and weight maintenance leads to negligible changes in central adiposity.
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A scalable, virtual weight management program tailored for adults with type 2 diabetes: effects on glycemic control.
Apolzan, JW, LaRose, JG, Anton, SD, Beyl, RA, Greenway, FL, Wickham, EP, Lanoye, A, Harris, MN, Martin, CK, Bullard, T, et al
Nutrition & diabetes. 2023;(1):3
Abstract
BACKGROUND The objective was to test the efficacy of a scalable, virtually delivered, diabetes-tailored weight management program on glycemic control in adults with type 2 diabetes (T2D). METHODS This was a single arm, three-site clinical trial. Participants had baseline HbA1c between 7-11% and BMI between 27-50 kg/m2. Primary outcome was change in HbA1c at 24 weeks. Secondary outcomes were changes in body weight, waist circumference, the Diabetes Distress Scale (DDS), quality of life (IWQOL-L), and hunger (VAS). Generalized linear effects models were used for statistical analysis. RESULTS Participants (n = 136) were 56.8 ± 0.8 y (Mean ± SEM), 36.9 ± 0.5 kg/m2, 80.2% female, 62.2% non-Hispanic white. Baseline HbA1c, weight, and total DDS score were 8.0 ± 0.09%, 101.10 ± 1.47 kg, and 2.35 ± 0.08, respectively. At week 24, HbA1c, body weight, and total DDS decreased by 0.75 ± 0.11%, 5.74 ± 0.50%, 0.33 ± 0.10 units, respectively (all p < 0.001). Also, at week 24, quality of life increased by 9.0 ± 1.2 units and hunger decreased by 14.3 ± 2.4 units, (both p < 0.0001). CONCLUSIONS The scalable, virtually delivered T2D-tailored weight management program had favorable and clinically meaningful effects on glycemic control, body weight, and psychosocial outcomes.
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Early time-restricted eating affects weight, metabolic health, mood, and sleep in adherent completers: A secondary analysis.
Steger, FL, Jamshed, H, Bryan, DR, Richman, JS, Warriner, AH, Hanick, CJ, Martin, CK, Salvy, SJ, Peterson, CM
Obesity (Silver Spring, Md.). 2023;(Suppl 1):96-107
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Abstract
OBJECTIVE Data are mixed on whether intermittent fasting improves weight loss and cardiometabolic health. Here, the effects of time-restricted eating (TRE) in participants who consistently adhered ≥5 d/wk every week were analyzed. METHODS Ninety patients aged 25 to 75 years old with obesity were randomized to early TRE (eTRE; 8-hour eating window from 07:00 to 15:00) or a control schedule (≥12-hour window) for 14 weeks. A per-protocol analysis of weight loss, body composition, cardiometabolic health, and other end points was performed. RESULTS Participants who adhered to eTRE ≥5 d/wk every week had greater improvements in body weight (-3.7 ± 1.2 kg; p = 0.003), body fat (-2.8 ± 1.3 kg; p = 0.04), heart rate (-7 ± 3 beats/min; p = 0.02), insulin resistance (-2.80 ± 1.36; p = 0.047), and glucose (-9 ± 5 mg/dL; p = 0.047) relative to adherers in the control group. They also experienced greater improvements in mood, including fatigue and anger; however, they self-reported sleeping less and taking longer to fall asleep. CONCLUSIONS For those who can consistently adhere at least 5 d/wk, eTRE is a valuable approach for improving body weight, body fat, cardiometabolic health, and mood. Further research is needed to determine whether eTRE's effects of shortening sleep but reducing fatigue are healthful or not.
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The Personalized Nutrition Study (POINTS): evaluation of a genetically informed weight loss approach, a Randomized Clinical Trial.
Höchsmann, C, Yang, S, Ordovás, JM, Dorling, JL, Champagne, CM, Apolzan, JW, Greenway, FL, Cardel, MI, Foster, GD, Martin, CK
Nature communications. 2023;(1):6321
Abstract
Weight loss (WL) differences between isocaloric high-carbohydrate and high-fat diets are generally small; however, individual WL varies within diet groups. Genotype patterns may modify diet effects, with carbohydrate-responsive genotypes losing more weight on high-carbohydrate diets (and vice versa for fat-responsive genotypes). We investigated whether 12-week WL (kg, primary outcome) differs between genotype-concordant and genotype-discordant diets. In this 12-week single-center WL trial, 145 participants with overweight/obesity were identified a priori as fat-responders or carbohydrate-responders based on their combined genotypes at ten genetic variants and randomized to a high-fat (n = 73) or high-carbohydrate diet (n = 72), yielding 4 groups: (1) fat-responders receiving high-fat diet, (2) fat-responders receiving high-carbohydrate diet, (3) carbohydrate-responders receiving high-fat diet, (4) carbohydrate-responders receiving high-carbohydrate diet. Dietitians delivered the WL intervention via 12 weekly diet-specific small group sessions. Outcome assessors were blind to diet assignment and genotype patterns. We included 122 participants (54.4 [SD:13.2] years, BMI 34.9 [SD:5.1] kg/m2, 84% women) in the analyses. Twelve-week WL did not differ between the genotype-concordant (-5.3 kg [SD:1.0]) and genotype-discordant diets (-4.8 kg [SD:1.1]; adjusted difference: -0.6 kg [95% CI: -2.1,0.9], p = 0.50). With the current ability to genotype participants as fat- or carbohydrate-responders, evidence does not support greater WL on genotype-concordant diets. ClinicalTrials identifier: NCT04145466.
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Protocol to evaluate the effectiveness and cost-effectiveness of an environmental nutrition and physical activity intervention in nurseries (Nutrition and Physical Activity Self Assessment for Child Care - NAP SACC UK): a multicentre cluster randomised controlled trial.
Kipping, R, Pallan, M, Hannam, K, Willis, K, Dobell, A, Metcalfe, C, Jago, R, Johnson, L, Langford, R, Martin, CK, et al
Research square. 2023
Abstract
UNLABELLED Background One in seven UK children have obesity when starting school, with higher prevalence associated with deprivation. Most pre-school children do not meet UK recommendations for physical activity and nutrition. Formal childcare settings provide opportunities to deliver interventions to improve nutritional quality and physical activity to the majority of 3-4-year-olds. The nutrition and physical activity self-assessment for childcare (NAP SACC) intervention has demonstrated effectiveness in the USA with high acceptability in the UK. The study aims to evaluate the effectiveness and cost-effectiveness of the NAP SACC UK intervention to increase physical activity, reduce sedentary time and improve nutritional intake. Methods Multi-centre cluster RCT with process and economic evaluation. Participants are children aged 2 years or over, attending UK early years settings (nurseries) for ≥ 12 hours/week or ≥ 15 hours/week during term time and their parents, and staff at participating nurseries. The 12-month intervention involves nursery managers working with a Partner (public health practitioner) to self-assess policies and practices relating to physical activity and nutrition; nursery staff attending one physical activity and one nutrition training workshop and setting goals to be achieved within six months. The Partner provides support and reviews progress. Nursery staff receive a further workshop and new goals are set, with Partner support for a further six months. The comparator is usual practice. Up to 56 nurseries will be stratified by area and randomly allocated to intervention or comparator arm with minimisation of differences in level of deprivation. PRIMARY OUTCOMES accelerometer-assessed mean total activity time on nursery days and average total energy (kcal) intake per eating occasion of lunch and morning/afternoon snacks consumed within nurseries. SECONDARY OUTCOMES accelerometer-assessed mean daily minutes of moderate-to-vigorous physical activity and sedentary time per nursery day, total physical activity on nursery days compared to non-nursery days, average serving size of lunch and morning/afternoon snacks in nursery per day, average percentage of core and non-core food in lunch and morning/afternoon snacks, zBMI, proportion of children who are overweight/obese and child quality-of-life. A process evaluation will examine fidelity, acceptability, sustainability and context. An economic evaluation will compare costs and consequences from the perspective of the local government, nursery and parents. TRIAL REGISTRATION ISRCTN33134697.
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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
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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:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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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.
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Impact of early time-restricted eating on diet quality, meal frequency, appetite, and eating behaviors: A randomized trial.
Steger, FL, Jamshed, H, Martin, CK, Richman, JS, Bryan, DR, Hanick, CJ, Salvy, SJ, Warriner, AH, Peterson, CM
Obesity (Silver Spring, Md.). 2023;(Suppl 1):127-138
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OBJECTIVE Time-restricted eating (TRE) can reduce body weight, but it is unclear how it influences dietary patterns and behavior. Therefore, this study assessed the effects of TRE on diet quality, appetite, and several eating behaviors. METHODS Adults with obesity were randomized to early TRE plus energy restriction (eTRE + ER; 8-hour eating window from 7:00 a.m. to 3:00 p.m.) or a control eating schedule plus energy restriction (CON + ER; ≥12-hour window) for 14 weeks. Food intake was assessed via the Remote Food Photography Method, while eating patterns, appetite, and eating behaviors were assessed via questionnaires. RESULTS A total of 59 participants completed the trial, of whom 45 had valid food records. eTRE + ER did not affect eating frequency, eating restraint, emotional eating, or the consistency of mealtimes relative to CON + ER. eTRE + ER also did not affect overall diet quality. The intensity and frequency of hunger and fullness were similar between groups, although the eTRE + ER group was hungrier while fasting. CONCLUSIONS When combined with a weight-loss program, eTRE does not affect diet quality, meal frequency, eating restraint, emotional eating, or other eating behaviors relative to eating over more than a 12-hour window. Rather, participants implement eTRE as a simple timing rule by condensing their normal eating patterns into a smaller eating window.
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Protocol to evaluate the effectiveness and cost-effectiveness of an environmental nutrition and physical activity intervention in nurseries (Nutrition and Physical Activity Self Assessment for Child Care - NAP SACC UK): a multicentre cluster randomised controlled trial.
Kipping, R, Pallan, M, Hannam, K, Willis, K, Dobell, A, Metcalfe, C, Jago, R, Johnson, L, Langford, R, Martin, CK, et al
BMC public health. 2023;(1):1475
Abstract
BACKGROUND One in seven UK children have obesity when starting school, with higher prevalence associated with deprivation. Most pre-school children do not meet UK recommendations for physical activity and nutrition. Formal childcare settings provide opportunities to deliver interventions to improve nutritional quality and physical activity to the majority of 3-4-year-olds. The nutrition and physical activity self-assessment for childcare (NAP SACC) intervention has demonstrated effectiveness in the USA with high acceptability in the UK. The study aims to evaluate the effectiveness and cost-effectiveness of the NAP SACC UK intervention to increase physical activity, reduce sedentary time and improve nutritional intake. METHODS Multi-centre cluster RCT with process and economic evaluation. Participants are children aged 2 years or over, attending UK early years settings (nurseries) for ≥ 12 h/week or ≥ 15 h/week during term time and their parents, and staff at participating nurseries. The 12-month intervention involves nursery managers working with a Partner (public health practitioner) to self-assess policies and practices relating to physical activity and nutrition; nursery staff attending one physical activity and one nutrition training workshop and setting goals to be achieved within 6 months. The Partner provides support and reviews progress. Nursery staff receive a further workshop and new goals are set, with Partner support for a further 6 months. The comparator is usual practice. Up to 56 nurseries will be stratified by area and randomly allocated to intervention or comparator arm with minimisation of differences in level of deprivation. PRIMARY OUTCOMES accelerometer-assessed mean total activity time on nursery days and average total energy (kcal) intake per eating occasion of lunch and morning/afternoon snacks consumed within nurseries. SECONDARY OUTCOMES accelerometer-assessed mean daily minutes of moderate-to-vigorous physical activity and sedentary time per nursery day, total physical activity on nursery days compared to non-nursery days, average serving size of lunch and morning/afternoon snacks in nursery per day, average percentage of core and non-core food in lunch and morning/afternoon snacks, zBMI, proportion of children who are overweight/obese and child quality-of-life. A process evaluation will examine fidelity, acceptability, sustainability and context. An economic evaluation will compare costs and consequences from the perspective of the local government, nursery and parents. TRIAL REGISTRATION ISRCTN33134697, 31/10/2019.
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Simply Dinner: A Randomized Controlled Trial of Home Meal Delivery.
Brophy-Herb, HE, Martoccio, TL, Kerver, JM, Choi, HH, Jeanpierre, LA, Williams, J, Mitchell, K, Martin, CK, Sturza, J, Contreras, DA, et al
Academic pediatrics. 2023;(5):952-962
Abstract
OBJECTIVE To determine the effect of a bundled intervention (home meal delivery and provision of cooking/serving resources) on preschoolers' body mass index z-score (BMIz), dietary quality, and family meal frequency. METHODS Participants (299 families; mean child age 4.4 years, 47% male, 55% White, 18% Black, 27% Hispanic or other race and ethnicity, and 25% were overweight or obese) were randomized to a control group or to provision of cooking/serving resources plus home meal delivery for 12 weeks (meals provided by Meals on Wheels [MOW cohort, n = 83] or a commercial service [COM cohort, n = 216]). Outcomes were child dietary quality, family meal frequency, and child BMIz. RESULTS The intervention increased dinnertime intake of red and orange vegetables in the full sample (MOW cohort+COM cohort) (0.10 pre- to 0.15 cup equivalents (CE) post-in the intervention group vs 0.10 pre- to 0.09 post- in the control group; P = .01) and the COM cohort (0.11 pre- to 0.17 CE post- vs 0.11 pre- to 0.09 post-; P = .002), and typical daily dietary intake of fruit and fruit juice in the MOW cohort (1.50 CE pre- to 1.66 post- vs 1.48 pre- to 1.19 post-; P = .05). The intervention did not change meal frequency or BMIz. CONCLUSIONS Short-term home meal delivery with provision of cooking/serving resources improved dietary quality among preschool-aged children but did not change meal frequency or BMIz. Expansion of Meals on Wheels programs to preschool-aged children may be a promising intervention to improve dietary quality. Family meals, when already frequent, are not further increased by reducing the burden of meal preparation.