Abstract
BACKGROUND.
Intentional weight-loss improves physical function among older adults with obesity, despite the associated lean mass loss. However, prior studies have not assessed impacts of weight-loss on physical function and body composition among older adults with type 2 diabetes mellitus (T2DM) and obesity, a population at high-risk for sarcopenia and functional decline. Our objective was to examine differences in body composition changes by physical function status among middle-aged and older adults with T2DM and overweight/obesity participating in an intensive weight-loss intervention of diet and exercise over 12 months.
METHODS.
We conducted a secondary analysis of 12-month data from the Look AHEAD dual-energy X-ray absorptiometry (DXA) substudy among participants randomized to intervention (n=603). Independent variables included DXA-derived percent change in appendicular lean mass (ALM) and fat mass (FM). The dependent variable was SF-36 physical function subscale change categorized as worsened (decrease ≥5), stable (change ±4), or improved (increase ≥5). We examined the associations using ANOVA.
RESULTS.
Overall, participants had a mean age of 58.3 (SD 6.7) and 63% were women – 8% had worsened, 69% stable, and 22% improved physical function. Differences in mean percent ALM change between physical function groups were non-significant (worsened −3.7%; stable −4.8%; improved −5.6% (p=0.05)). Mean percent FM change was significantly different across physical function groups (worsened −9.3%; stable −14.6%; improved −17.9% (p<0.01)).
CONCLUSIONS.
Lean mass loss associated with lifestyle weight-loss intervention does not negatively impact physical function, rather the intervention appears to improve physical function by reducing adiposity among adults with T2DM and overweight/obesity.
Keywords: Body Composition, Functional Performance, Obesity, Diabetes, Caloric Restriction
INTRODUCTION
Obesity compounds the impacts of aging by exacerbating functional decline and chronic disease burden in older adults (1). Obesity, defined as a body mass index (BMI) ≥30 kg/m2, is estimated to impact 45% of middle-aged adults and 43% of older adults in the U.S. with projected rise in prevalence (2,3). Obesity leads to fat infiltration into the muscle tissue, resulting in poor muscle quality and, in turn, functional impairment (4). Type 2 diabetes mellitus (T2DM) is highly prevalent among older adults and often co-occurs with obesity (5). T2DM is an independent risk factor for the loss of muscle mass, which leads to decline in muscle strength and function (5–7). Thus, older adults with obesity and T2DM represent a population at particularly high risk for an accelerated decline in physical function. Therefore, identifying interventions that improve metabolic disease and preserve physical function in this group is a public health priority (8).
While weight reduction improves obesity-related conditions including T2DM (9), intentional weight loss is also associated with accompanying lean mass loss (10) that may worsen physical function. Older adults with T2DM are particularly vulnerable to lean mass loss (5); therefore, clinical guidelines recommend individualized lifestyle modification based on frailty status and consideration of physical function improvement as an important goal in this population (11). In a 12-month randomized controlled trial (RCT) among older adults with obesity and mild to moderate frailty, weight loss through a combination of diet and exercise significantly improved physical performance and physical function relative to study controls (12). The diet-exercise group achieved 9% mean weight loss along with preferential loss of fat mass [−6.3 kg (16% loss)] compared to lean mass [−1.8 kg (3% loss)], suggesting that loss of fat mass may be a driver of improvement in physical function. While physical function improved despite the loss of lean mass, this study did not target the high-risk group of individuals with T2DM and obesity. Given that T2DM and obesity are significant contributors to poor muscle function and physical impairment (4,5), additional research is needed to understand the impacts of weight loss on body composition and physical function in this population.
In this study, we conducted a secondary analysis of the Look AHEAD trial – a RCT of an intensive lifestyle intervention (ILI) to reduce weight among middle-aged and older adults with T2DM and overweight/obesity – among a subgroup of ILI participants who underwent dual-energy X-ray absorptiometry (DXA). We aimed to examine the association between changes in body composition and physical function status over 12 months. We hypothesized that decreased lean mass would not negatively impact physical function and that reductions in fat mass and total body mass would be associated with physical function improvement.
METHODS
Study Design and Description of the Parent Study
This study was a secondary analysis of the Look AHEAD DXA substudy, in which a subgroup of ILI participants with DXA were used to evaluate the relationship between body composition changes and physical function over 12 months. The Look AHEAD trial was a U.S.-based multi-center RCT (NCT00017953) designed to compare the effects of ILI on cardiovascular mortality to a control group who received diabetes support and education (DSE). Look AHEAD randomized 5,145 middle-aged and older adults (aged 45–76) with T2DM and overweight/obesity (BMI ≥25 kg/m2). All participants provided informed consent and the study was approved by the Institutional Review Board at each site.
Look AHEAD participants were randomized to either ILI or DSE. ILI, designed to produce ≥10% weight reduction, focused on a reduced-calorie diet, physical activity goal ≥175 minutes of moderately intense activity weekly, and behavior modification — especially meal tracking — delivered through a standardized curriculum (13). Participants were encouraged to record their food intake and physical activity daily. The recommended calorie intake was 1200–1500 calories per day for participants weighing <114 kg and 1500–1800 calories per day for participants ≥114 kg, achieved through a portion-controlled diet. Participants had the option to choose partial meal replacements, replacing two meals and one snack, with one meal consisting of conventional foods from a detailed menu plan. Participants were encouraged to eat fruits and vegetables to reach their daily calorie goal and consume less than 30% of their calories from fat (and <10% from saturated fat). The focus was on caloric restriction and not on specific diet patterns.
In terms of physical activity, participants were initially encouraged to engage in unsupervised moderately intense physical activity (brisk walking or a similar aerobic activity) for 50 minutes/week with the goal to gradually increase physical activity to ≥175 minutes/week by 6 months. For 12 months, participants attended a combination of group and individual intervention sessions designed to support participants’ behavior modification. During these sessions, participants had the opportunity to share their food intake and physical activity logs and whether they met their weekly goals. All routine care was provided by the participants’ individual physicians.
At five study sites (Baton Rouge, Louisiana; Boston, Massachusetts; Houston, Texas; Los Angeles, California; Seattle, Washington), participants underwent DXA at baseline and 12 months to measure body composition (n=1,373). DXA was measured using Hologic (QDR 4500A) fan beam densitometer. Correctional factors were applied to account for underestimation of lean mass (LM) and overestimation of fat mass (FM) with QDR 4500A (14). Additionally, calibration was conducted to ensure consistency across the five sites.
Population for this Study
Given that our study focused on the impact of ILI-induced weight reduction on body composition and physical function, we limited the analytic sample to ILI participants who took part in the DXA substudy and had physical function scores at baseline and 12 months (10 with incomplete scores). We also limited the sample to participants who identified as non-Hispanic white, non-Hispanic black, and Hispanic, as the ‘other’ race category was heterogeneous (n=29) (e.g. Asian, Native American), resulting in 603 participants in the analytic sample.
Measures
The independent variables were body composition changes between baseline and 12 months, specifically percent change in appendicular lean mass (ALM), fat mass (FM), and total body mass (TBM). ALM, which represents the amount of lean tissue in the arms and legs excluding bone, is a common measure to estimate total body skeletal muscle mass (15). We derived ALM and FM from DXA. For TBM, we used weight measured by a digital scale.
The dependent variable was change between baseline and 12 months in self-reported physical function assessed with the validated SF-36 physical function subscale score, which is clinically relevant (16). The SF-36 physical function subscale uses 10 questions to assess to what degree participants felt limited in various activities (a lot, a little, not at all). ‘Limited a lot, ‘limited a little,’ and ‘limited not at all’ were assigned scores of 0, 50, and 100, respectively. Scores were averaged to obtain the composite physical function score, which was then converted to a T-score (mean 50, SD 10) based on the scores of the general U.S. population (17). Scores range from 0–100, with higher scores indicating better physical function. We categorized scores into clinically meaningful groups: worsened, stable and improved. We used the minimum clinically important difference of a 5-point change to define the physical function change groups (18): worsened (decrease ≥ 5 points), stable (change ±4 points), and improved (increase ≥ 5 points). The stable physical function group served as the reference group in analyses.
Covariates included age, gender, and baseline BMI. We also considered race and baseline assessments of diabetes severity including hemoglobin A1c, diabetes duration, and insulin use.
Statistical Analysis
We used IBM SPSS Statistics, version 29 for data analysis and used chi-squared test and ANOVA to examine differences in baseline attributes by physical function groups. To examine the association between independent variables (i.e., percent change in ALM, FM, and TBM) and change in physical function groups, we conducted bivariate analyses using ANOVA.
To examine influences of potential confounders and confirm bivariate results, we used multinomial logistic regression adjusted for age, gender, and baseline BMI. We selected these covariates given their prior associations with body composition and physical function (15); furthermore, given that BMI and FM are known to be correlated (19), we elected to adjust for only BMI.
We used separate multinomial logistic regression models to characterize how percent change in each of the body composition variables influenced the probability of being in one of the three physical function change groups. The regression models for ALM and FM represent 1% change increments in these variables (to reflect magnitude of expected 12-month changes (20,21)) while TBM was scaled to represent 5% change increments to reflect a clinically significant magnitude of weight change. As race has been associated with body composition, we conducted a sensitivity analysis that included race in the multinomial regression model. Results were similar (eTables 1–3), as race was not a statistically significant variable. We also conducted a sensitivity analysis including baseline A1C, diabetes duration, and insulin use, but these covariates did not impact the association (eTables 1–3). We ultimately opted for a parsimonious approach (22), and therefore, only present results adjusted for age, gender, and baseline BMI.
RESULTS
Overall, 603 participants were included in the analyses, with a mean age of 58.3 years (SD 6.7), 63% were women, and 61% were non-Hispanic white. Table 1 shows the baseline attributes overall and by physical function change groups – 8% had worsened physical function, 69% were stable, and 22% had improved physical function. There were no significant between-group differences at baseline with respect to age, gender, race, hemoglobin A1C, diabetes duration, or insulin use. Mean BMI and FM were lower among the stable physical function group relative to the worsened and improved physical function groups. However, there was no significant difference in baseline ALM between groups. Mean values at each timepoint as well as absolute changes in body composition and physical function are provided in Table 2. Mean (SD) change in ALM was −0.9 kg (1.3) for the worsened group, −1.1 (1.1) for the stable group, and −1.2 (1.1) for the improved group. FM decreased incrementally by 4.2 kg (SD 5.1), 5.6 (4.5), and 7.5 (5.6) in the worsened, stable, and improved physical function change groups, respectively. Similarly, TBM decreased by 6.7 kg (SD 6.6) for the worsened group, 8.7 (6.2) for the stable group, and 10.9 (7.1) for the improved group. Finally, mean (SD) change in physical function score was −11.6 (5.4) for the worsened group, +0.8 (2.4) for the stable group, and +10.3 (4.9) for the improved group (Table 2).
Table 1.
Baseline attributes by change in physical function at 12 months among participants randomized to intensive lifestyle intervention for weight reduction in the Look AHEAD trial
| Participant Attributes | Overall (n=603) | Change in Physical Functiona | p-valueb | ||
|---|---|---|---|---|---|
| Worsened (n=48) | Stable (n=423) | Improved (n=132) | |||
| Demographics | |||||
| Mean age in years (SD) | 58.3(6.7) | 57.7(6.9) | 58.2(6.7) | 58.9 (6.8) | 0.49 |
| Age group, n (%) | |||||
| <60 years | 341 (56.6) | 29 (60.4) | 247 (72.4) | 65 (49.2) | 0.15 |
| ≥60 years | 262 (43.4) | 19 (39.6) | 176 (41.6) | 67 (50.8) | |
| Women, n (%) | 382 (63.3) | 35 (72.9) | 87 (65.9) | 260 (61.5) | 0.23 |
| Race/ethnicityc, n (%) | |||||
| Non-Hispanic White | 370 (61.4) | 29 (60.4) | 262 (61.9) | 79 (59.8) | 0.32 |
| Non-Hispanic Black | 63 (10.4) | 9 (18.8) | 41 (9.7) | 13 (9.8) | |
| Hispanic | 170 (28.2) | 10 (20.8) | 120 (28.4) | 40 (30.3) | |
| Baseline Diabetes Status | |||||
| Mean hemoglobin A1C (SD) | 7.2% (1.2) | 6.9% (1.0) | 7.3% (1.2) | 7.2% (1.2) | 0.16 |
| Mean diabetes duration in years (SD)d | 6.2 (5.9) | 5.2 (5.9) | 6.2 (6.0) | 6.9 (5.7) | 0.18 |
| Insulin use, n (%) | 94 (15.6) | 6 (12.5) | 60 (14.2) | 28 (21.2) | 0.13 |
| Baseline Body Composition | |||||
| Mean BMI in kg/m2 (SD) | 35.1 (5.4) | 36.2 (5.9) | 34.7 (5.3) | 36.0 (5.6) | 0.02 |
| Mean appendicular lean mass in kg (SD)d | 22.8 (5.1) | 22.6 (5.3) | 22.9 (5.0) | 22.6 (5.2) | 0.73 |
| Mean fat mass in kg (SD)d | 40.0 (10.7) | 42.8 (11.8) | 39.1 (10.6) | 41.9 (10.5) | <0.01 |
| Mean total body mass in kg (SD) | 96.2 (17.0) | 97.8 (17.0) | 95.6 (16.9) | 97.8 (16.9) | 0.37 |
Note. Abbreviations: BMI = body mass index.
Physical function measured by the SF-36 physical function subscale score at baseline and 12-month follow-up, change between timepoints was categorized as follows: worsened (decrease ≥ 5 points), stable (change ±4 points), and improved (increase ≥ 5 points).
To calculate p-values for differences between groups, we used a Χ2 test statistic for categorical variables and an F-statistic for continuous variables.
Individuals from the ‘other’ race category (n=29) were excluded from the analytic sample.
There were three participants missing diabetes duration data (n=600). There were four participants with incomplete dual-energy X-ray absorptiometry data; therefore, mean appendicular lean mass and fat mass were calculated from the remaining (n=599).
p<0.05
Table 2.
Appendicular lean mass, fat mass, total body weight, and physical function at baseline, 12 months, and absolute change between timepoints, overall and by change in physical function groups
| Change in Physical Function a | Overall (n=603) | |||
|---|---|---|---|---|
| Worsened (n=48) | Stable (n=423) | Improved (n=132) | ||
| Mean Appendicular Lean Mass, kg (SD) b | ||||
| Baseline | 22.6 (5.3) | 22.9 (5.0) | 22.6 (5.2) | 22.8 (5.1) |
| 12 months | 21.7 (5.0) | 21.9 (4.9) | 21.3 (5.2) | 21.7 (5.0) |
| Change (12 months-Baseline) | −0.9 (1.3) | −1.1 (1.1) | −1.2 (1.1) | −1.1 (1.1) |
| Mean Fat Mass, kg (SD) b | ||||
| Baseline | 42.8 (11.8) | 39.1 (10.6) | 41.9 (10.5) | 40.0 (10.7) |
| 12 months | 38.6 (11.0) | 33.6 (10.6) | 34.4 (10.2) | 34.1 (10.6) |
| Change (12 months-Baseline) | −4.2 (5.1) | −5.6 (4.5) | −7.5 (5.6) | −5.9 (4.9) |
| Mean Total Body Mass, kg (SD) | ||||
| Baseline | 97.8 (17.0) | 95.6 (16.9) | 97.8 (16.8) | 96.3 (16.9) |
| 12 months | 91.2 (17.0) | 87.0 (16.3) | 86.8 (15.9) | 87.3 (16.3) |
| Change (12 months-Baseline) | −6.7 (6.6) | −8.7 (6.2) | −10.9 (7.1) | −9.0 (6.6) |
| Mean Physical Function Score (SD) | ||||
| Baseline | 49.5 (6.8) | 51.5 (5.7) | 41.7 (7.7) | 49.2 (7.4) |
| 12 months | 37.9 (9.1) | 52.3 (5.9) | 52.0 (5.5) | 51.1 (7.2) |
| Change (12 months-Baseline) | −11.6 (5.4) | 0.8 (2.4) | 10.3 (4.9) | 1.9 (6.5) |
Physical function measured by the SF-36 physical function subscale score at baseline and 12-month follow-up, change between timepoints was categorized as follows: worsened (decrease ≥ 5 points), stable (change ±4 points), and improved (increase ≥ 5 points). The SF-36 physical function subscale scores can range from 0–100, with higher scores indicating better physical function.
There were four participants with incomplete dual-energy X-ray absorptiometry data; therefore, appendicular lean mass and fat mass calculated from the remaining (n=599).
In bivariate analysis, mean (SD) percent ALM change did not differ significantly across physical function change groups [worsened −3.7% (5.7), stable −4.8% (4.8), and improved −5.6% (5.0); p = 0.05] (Figure 1). In contrast, greater mean (SD) FM reduction was associated with better physical function change–FM decreased incrementally by 9.3% (12.4), 14.6% (11.3), and 17.9% (12.3) in the worsened, stable, and improved PF groups (p<0.01), respectively. Similarly, mean (SD) percent TBM loss significantly differed between groups, with incremental weight loss as physical function improved [worsened −6.8% (6.9), stable −9.0% (6.0), improved −11.1% (6.5); p<0.01] (Figure 1).
Figure 1. Percent changes in body composition by physical function change groups at 12 months among participants randomized to intensive lifestyle intervention for weight reduction in the Look AHEAD trial.
Data displayed are bivariate associations between percent change in body composition and physical function change groups, which was analyzed using ANOVA to examine between-group differences. Physical function categories defined as: worsened (decrease ≥ 5 points), stable (change ±4 points), and improved (increase ≥ 5 points); which represent minimum clinically important differences in the SF-36 physical function subscale score. Worsened physical function represented by black bars, stable physical function as grey bars, and improved physical function as white bars.
Multinomial logistic regression analyses, adjusted for age, gender, and baseline BMI, confirmed findings from the bivariate results. There was no significant association between percent ALM change and either improved physical function [OR 0.97; 95%CI 0.93–1.01; p = 0.10] or worsened physical function [OR 1.05; 95%CI 0.98–1.11; p = 0.15] as compared to the stable physical function group. Both FM and TBM changes were significantly associated with physical function. For every 1% increase in FM and 5% increase in TBM, there was an increase in the odds of being in the worsened physical function group compared to the stable physical function group [FM: OR 1.04; 95%CI 1.01–1.07; p <0.01. TBM: OR 1.37; 95%CI 1.07–1.74; p = 0.01]. Conversely, for every 1% increase in FM and 5% increase in TBM, there was a decrease in the odds of being in the improved physical function compared to the stable physical function group [FM: OR 0.97; 95%CI 0.96–0.99; p <0.01. TBM: OR 0.78; 95%CI 0.67–0.91; p <0.01].
DISCUSSION
In middle-aged and older adults with T2DM and overweight/obesity participating in an intensive lifestyle intervention, this study found that greater FM and TBM loss were associated with improved physical function over 12 months. Greater reductions in FM and TBM were significantly less likely to be associated with worsened physical function, even when accounting for factors known to influence body composition and physical function including age. Overall, reduction in ALM was small–mean loss of 1.1 kg between baseline and 12 months and was not significantly associated with either improved or worsened physical function. Our findings suggest that weight loss through diet and exercise improves physical function by reducing FM among a high-risk population of adults with T2DM and overweight/obesity.
Physical function–given its implications for quality of life and mortality (1)–is an important outcome for adults as they age. A prior Look AHEAD analysis (23) showed that the ILI group had a significant improvement in self-reported physical function compared to the control group at 12 months and this improvement was maintained at 8-year follow-up. Another Look AHEAD analysis (24) had similar findings at long-term follow-up with an objective physical function measure: ILI participants had faster gait speed and physical performance at ~8 years of follow-up compared to the control group. However, these studies did not assess physical function in the context of body composition changes and at an important time-point at 12 months when the intensive phase of the lifestyle intervention concluded.
A seminal RCT by Villareal and colleagues demonstrated that physical function improved despite a mean 1.8 kg total lean mass loss over 12 months among older adults with mild to moderate frailty participating in a diet-exercise intervention to lose weight (12). Our study, among high-risk individuals with T2DM and obesity, similarly found no association between an average 1.1 kg ALM loss and physical function at 12 months. By examining the 12-month outcomes, we were able to examine the associations between body composition and physical function most proximal to the conclusion of the intensive phase of the lifestyle intervention, and we are unaware of another study examining the association of body composition and physical function at this timepoint for individuals with T2DM and obesity. Although not specific to older adults, weight loss in adults with T2DM and overweight/obesity has been recommended to mitigate diabetes-related complications (25). Based on our findings, clinicians may consider recommending weight reduction through diet and exercise for middle-aged and older adults with T2DM and obesity without concern for impaired physical function due to lean mass loss. In our study, 8% of participants had worsened physical function, which may be attributed to smaller reductions in FM and TBM. Therefore, monitoring of physical function status may still be prudent in the clinical setting, particularly among patients who achieve less weight loss.
Rather than concern about lean mass loss, evidence suggests that reducing adiposity is an important driver that predicts physical function improvement (26). Our study among middle-aged and older adults with T2DM and overweight/obesity confirmed these prior findings. Maintaining FM reduction may differ by sex long-term, as a Look AHEAD subgroup analysis found that ILI-induced changes in FM was maintained at 4 years in both men and women, but only in women at 8 years (27). Benefits of reduction in adiposity extend beyond physical function into cardiometabolic health. A recent Look AHEAD analysis demonstrated an association between reductions in FM and improvements in glycemic control as well as decreased odds of insulin use (28). Reduction in adiposity also leads to improvements in other cardiometabolic conditions including sleep apnea, hypertension, dyslipidemia, and chronic kidney disease (9).
Other trials of lifestyle interventions for weight reduction have excluded participants with insulin-dependent diabetes (29,30); however, 15% of the participants in our sample used insulin. Interestingly, we found no significant associations between various measures of diabetes status at baseline–hemoglobin A1c, diabetes duration, and insulin use–with change in physical function. Our results suggest that individuals with insulin-dependent diabetes also benefit from intensive lifestyle intervention without increased risk for decline in physical function.
This study has several limitations. We used DXA-derived body composition data, which only provides an estimate of muscle mass. DXA is also infrequently used in clinical settings to measure body composition. We used the self-reported SF-36 physical function score, as objective physical function measures were not collected at our study timepoints. Although the magnitude of the between-group differences in ALM loss was relatively small and the associations with physical function were not statistically significant, future studies should assess the association using objective physical function measures to assess clinical significance. There may be additional covariates that we did not include that may have attenuated the estimates, although a sensitivity analysis adjusted for baseline hemoglobin A1C, diabetes duration, and insulin use did not change our results. The Look AHEAD study is not applicable to adults with frailty and those without T2DM. Furthermore, generalizability is limited in racial minorities. The Look AHEAD study predates the approval of nutrient-stimulated hormone-based anti-obesity medications, which have raised concerns regarding extensive loss of lean mass (31).
Lastly, we were unable to assess the impact of dietary adherence and physical activity on body composition and physical function in this analysis as this data was not widely available in our analytic sample. A prior Look AHEAD analysis in a subgroup of participants who completed the food frequency questionnaire showed that ILI group, on average, consumed 1661 kcal/day (SD 659) (51% of energy intake from carbohydrates, 34% fat, and 18% protein) at 12 months (32). Additionally, ILI group engaged in 136.7 minutes (SD 110.4) of physical activity/week over 12 months and greater amount of physical activity correlated with 1-year weight loss outcomes (33). However, we cannot make inferences about how this may have impacted body composition and physical function. Future studies should assess specific physical activity and dietary strategies on body composition and physical function.
CONCLUSION
This subgroup analysis of the Look AHEAD trial showed that lean mass loss in the context of a lifestyle weight-loss intervention was not detrimental to physical function in middle-aged and older adults with T2DM and overweight/obesity. Rather, reduction in fat mass was associated with improved physical function. Overall, clinicians may consider recommending weight reduction through diet and exercise for middle-aged and older adults with T2DM and obesity without concern for impaired physical function due to lean mass loss.
Supplementary Material
ACKNOWLEDGEMENTS
We thank Nowella Durkin for her efforts in generating and sharing clinical trial data with the study team. The Look AHEAD clinical sites, coordinating center, central resource centers, and sponsors are acknowledged in Supplemental Material 1. KC conceptualized and designed the study as well as assisted with statistical analysis. AB conducted statistical analysis. DKH, EMS, LF, RK, JMC helped conceptualize the study. KAG helped conceptualize and design the analysis. All authors contributed to writing, review, and editing of the manuscript.
FUNDING
The Look AHEAD study was funded by the National Institutes of Health through cooperative agreements with the National Institute of Diabetes and Digestive and Kidney Diseases: DK57136, DK57149, DK56990, DK57177, DK57171, DK57151, DK57182, DK57131, DK57002, DK57078, DK57154, DK57178, DK57219, DK57008, DK57135, and DK56992. Additional funding was provided by the National Heart, Lung, and Blood Institute; National Institute of Nursing Research; National Center on Minority Health and Health Disparities; NIH Office of Research on Women’s Health; and the Centers for Disease Control and Prevention. This research was supported in part by the Intramural Research Program of the National Institute of Diabetes and Digestive and Kidney Diseases. The Indian Health Service (I.H.S.) provided personnel, medical oversight, and use of facilities. The opinions expressed in this paper are those of the authors and do not necessarily reflect the views of the funding sources. The full list of funding and support for the Look AHEAD study is provided in Supplemental Material 1. Additionally, this work was supported by the Health Services and Outcomes Research in Aging Population T32 (Grant Number T32AG066576).
Footnotes
DISCLOSURES
KAG served as the medical director for the American Board of Obesity Medicine, has been a paid scientific advisor to Novo Nordisk and Eli Lilly, and receives royalties from the Johns Hopkins ACG System. Since completion this work, KAG joined the American Board of Obesity Medicine Foundation as an employee. DKH serves as the NIH/NIA-appointed Data Safety Monitoring Board Chair and received National Dairy Council honoraria to present at the Nutrition and Wellness Science Forum. RK serves as the National Board of Directors in the American Diabetes Association. JMC has been a paid scientific advisor to Boehringer Ingelheim. All other authors declare that they have no competing interests.
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