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Weight Loss Programs May Have Beneficial or Adverse Effects on Fat Mass and Insulin Sensitivity in Overweight and Obese Black Women.

Leon B, Miller BV, Zalos G, Courville AB, Sumner AE, Powell-Wiley TM, Walter MF, Waclawiw MA, Cannon RO - J Racial Ethn Health Disparities (2014)

Bottom Line: Weight loss interventions have produced little change in insulin sensitivity in black women, but mean data may obscure metabolic benefit to some and adverse effects for others.Baseline SI (range 0.74 to 7.58 l/mU(-1)•min(-1)) was inversely associated with fat mass (r = -0.516, p < 0.001), independent of age.Additional support for participants who fail to achieve fat mass loss early in an intervention may be required for success.

View Article: PubMed Central - PubMed

Affiliation: Cardiovascular and Pulmonary Branch, National Heart, Lung, and Blood Institute, Building 10-CRC Room 5-3330, 10 Center Drive, Bethesda, MD 20892 USA.

ABSTRACT

Objective: Weight loss interventions have produced little change in insulin sensitivity in black women, but mean data may obscure metabolic benefit to some and adverse effects for others. Accordingly, we analyzed insulin sensitivity relative to fat mass change following a weight loss program.

Design and methods: Fifty-four black women (BMI range 25.9 to 54.7 kg/m(2)) completed the 6-month program that included nutrition information and worksite exercise facilities. Fat mass was measured by dual-energy X-ray absorptiometry, and insulin sensitivity index (SI) was calculated from an insulin-modified intravenous glucose tolerance test using the minimal model.

Results: Baseline SI (range 0.74 to 7.58 l/mU(-1)•min(-1)) was inversely associated with fat mass (r = -0.516, p < 0.001), independent of age. On average, subjects lost fat mass (baseline 40.8 ± 12.4 to 39.4 ± 12.6 kg [mean ± SD], P < 0.01), but 17 women (32 %) actually gained fat mass. SI for the group was unchanged (baseline 3.3 ± 1.7 to 3.2 ± 1.6, P = 0.67). However, the tertile with greatest fat mass loss (-3.6 kg, range -10.7 to -1.7 kg) improved insulin sensitivity (SI +0.3 ± 1.2), whereas the tertile with net fat mass gain (+0.9 kg, range -0.1 to +3.8 kg) had reduced insulin sensitivity (SI -0.7 ± 1.3) from baseline values (P < 0.05 by ANOVA).

Conclusions: Black women in a weight loss program who lose fat mass may have improved insulin sensitivity, but fat mass gain with diminished sensitivity is common. Additional support for participants who fail to achieve fat mass loss early in an intervention may be required for success.

No MeSH data available.


Related in: MedlinePlus

Tertiles of change in total (upper panel) and percent truncal fat mass (lower panel) and change in insulin sensitivity after completion of the 6-month weight loss program
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Fig3: Tertiles of change in total (upper panel) and percent truncal fat mass (lower panel) and change in insulin sensitivity after completion of the 6-month weight loss program

Mentions: Although on average subjects lost total fat mass and % truncal fat mass, 17 women (32 %) actually gained fat mass despite reporting energy intake reduction (−483 ± 697 vs. −287 ± 623 kcal/day), time devoted to daily walking (27 ± 25 vs. 17 ± 24 min) and aerobic exercise (7 ± 5 vs. 9 ± 10 min), and pedometer counts (5,574 ± 2,891 vs. 6,394 ± 3,895 steps/day) similar to the 37 who lost fat mass (all P > 0.2). Weight gain was observed with similar frequency among women who were overweight (4 of 16) or obese (11 of 38, P = 0.729) at the beginning of the program. There was a trend toward fewer women experiencing weight gain in the group randomized to attend nutrition instructional sessions (4 of 26) vs. those who were provided internet-based nutrition and exercise information only (11 of 28, P = 0.098). When participants were analyzed by tertiles of fat mass change and % truncal fat mass change, the tertile with the greatest fat mass loss improved insulin sensitivity in contrast to the tertile with net fat mass gain in which SI worsened (Fig. 3). By multivariable regression analysis, changes in either total fat mass (β = −0.038, P = 0.039) or % truncal fat mass (β = −0.047, P = 0.019) were independent predictors of change in SI, after adjustment for age, change in leptin, and change in VO2 peak.Fig. 3


Weight Loss Programs May Have Beneficial or Adverse Effects on Fat Mass and Insulin Sensitivity in Overweight and Obese Black Women.

Leon B, Miller BV, Zalos G, Courville AB, Sumner AE, Powell-Wiley TM, Walter MF, Waclawiw MA, Cannon RO - J Racial Ethn Health Disparities (2014)

Tertiles of change in total (upper panel) and percent truncal fat mass (lower panel) and change in insulin sensitivity after completion of the 6-month weight loss program
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4125812&req=5

Fig3: Tertiles of change in total (upper panel) and percent truncal fat mass (lower panel) and change in insulin sensitivity after completion of the 6-month weight loss program
Mentions: Although on average subjects lost total fat mass and % truncal fat mass, 17 women (32 %) actually gained fat mass despite reporting energy intake reduction (−483 ± 697 vs. −287 ± 623 kcal/day), time devoted to daily walking (27 ± 25 vs. 17 ± 24 min) and aerobic exercise (7 ± 5 vs. 9 ± 10 min), and pedometer counts (5,574 ± 2,891 vs. 6,394 ± 3,895 steps/day) similar to the 37 who lost fat mass (all P > 0.2). Weight gain was observed with similar frequency among women who were overweight (4 of 16) or obese (11 of 38, P = 0.729) at the beginning of the program. There was a trend toward fewer women experiencing weight gain in the group randomized to attend nutrition instructional sessions (4 of 26) vs. those who were provided internet-based nutrition and exercise information only (11 of 28, P = 0.098). When participants were analyzed by tertiles of fat mass change and % truncal fat mass change, the tertile with the greatest fat mass loss improved insulin sensitivity in contrast to the tertile with net fat mass gain in which SI worsened (Fig. 3). By multivariable regression analysis, changes in either total fat mass (β = −0.038, P = 0.039) or % truncal fat mass (β = −0.047, P = 0.019) were independent predictors of change in SI, after adjustment for age, change in leptin, and change in VO2 peak.Fig. 3

Bottom Line: Weight loss interventions have produced little change in insulin sensitivity in black women, but mean data may obscure metabolic benefit to some and adverse effects for others.Baseline SI (range 0.74 to 7.58 l/mU(-1)•min(-1)) was inversely associated with fat mass (r = -0.516, p < 0.001), independent of age.Additional support for participants who fail to achieve fat mass loss early in an intervention may be required for success.

View Article: PubMed Central - PubMed

Affiliation: Cardiovascular and Pulmonary Branch, National Heart, Lung, and Blood Institute, Building 10-CRC Room 5-3330, 10 Center Drive, Bethesda, MD 20892 USA.

ABSTRACT

Objective: Weight loss interventions have produced little change in insulin sensitivity in black women, but mean data may obscure metabolic benefit to some and adverse effects for others. Accordingly, we analyzed insulin sensitivity relative to fat mass change following a weight loss program.

Design and methods: Fifty-four black women (BMI range 25.9 to 54.7 kg/m(2)) completed the 6-month program that included nutrition information and worksite exercise facilities. Fat mass was measured by dual-energy X-ray absorptiometry, and insulin sensitivity index (SI) was calculated from an insulin-modified intravenous glucose tolerance test using the minimal model.

Results: Baseline SI (range 0.74 to 7.58 l/mU(-1)•min(-1)) was inversely associated with fat mass (r = -0.516, p < 0.001), independent of age. On average, subjects lost fat mass (baseline 40.8 ± 12.4 to 39.4 ± 12.6 kg [mean ± SD], P < 0.01), but 17 women (32 %) actually gained fat mass. SI for the group was unchanged (baseline 3.3 ± 1.7 to 3.2 ± 1.6, P = 0.67). However, the tertile with greatest fat mass loss (-3.6 kg, range -10.7 to -1.7 kg) improved insulin sensitivity (SI +0.3 ± 1.2), whereas the tertile with net fat mass gain (+0.9 kg, range -0.1 to +3.8 kg) had reduced insulin sensitivity (SI -0.7 ± 1.3) from baseline values (P < 0.05 by ANOVA).

Conclusions: Black women in a weight loss program who lose fat mass may have improved insulin sensitivity, but fat mass gain with diminished sensitivity is common. Additional support for participants who fail to achieve fat mass loss early in an intervention may be required for success.

No MeSH data available.


Related in: MedlinePlus