Stanley Heshka

Discrepancy between Self-Reported and Actual Caloric Intake and Exercise in Obese Subjects

BACKGROUND AND METHODS Some obese subjects repeatedly fail to lose weight even though they report restricting their caloric intake to less than 1200 kcal per day. We studied two explanations for this apparent resistance to diet--low total energy expenditure and underreporting of caloric intake--in 224 consecutive obese subjects presenting for treatment. Group 1 consisted of nine women and one man with a history of diet resistance in whom we evaluated total energy expenditure and its main thermogenic components and actual energy intake for 14 days by indirect calorimetry and analysis of body composition. Group 2, subgroups of which served as controls in the various evaluations, consisted of 67 women and 13 men with no history of diet resistance. RESULTS Total energy expenditure and resting metabolic rate in the subjects with diet resistance (group 1) were within 5 percent of the predicted values for body composition, and there was no significant difference between groups 1 and 2 in the thermic effects of food and exercise. Low energy expenditure was thus excluded as a mechanism of self-reported diet resistance. In contrast, the subjects in group 1 underreported their actual food intake by an average (+/- SD) of 47 +/- 16 percent and overreported their physical activity by 51 +/- 75 percent. Although the subjects in group 1 had no distinct psychopathologic characteristics, they perceived a genetic cause for their obesity, used thyroid medication at a high frequency, and described their eating behavior as relatively normal (all P < 0.05 as compared with group 2). CONCLUSIONS The failure of some obese subjects to lose weight while eating a diet they report as low in calories is due to an energy intake substantially higher than reported and an overestimation of physical activity, not to an abnormality in thermogenesis.

Waist Circumference Correlates with Metabolic Syndrome Indicators Better Than Percentage Fat

Objective: Percent fat is often considered the reference for establishing the magnitude of adipose tissue accumulation and the risk of excess adiposity. However, the increasing recognition of a strong link between central adiposity and metabolic disturbances led us to test whether waist circumference (WC) is more highly correlated with metabolic syndrome components than percent fat and other related anthropometric measures such as BMI.

Adipose tissue distribution is different in type 2 diabetes

BACKGROUND The extent to which adipose tissue (AT) distribution is different between persons with type 2 diabetes (T2DM) and nondiabetic control subjects remains unclear. OBJECTIVE The aim of this study was to establish whether total body adiposity and its distribution, quantified by using state-of-the-art whole-body magnetic resonance imaging, differs between these 2 groups. DESIGN This cross-sectional evaluation included 93 participants (n = 56 women and 37 men) in the Look AHEAD (Action for HEAlth in Diabetes) Trial with T2DM who had a mean (+/-SD) age of 58.3 +/- 6.6 y and body mass index (in kg/m(2)) of 31.6 +/- 3.1 and 93 healthy non-T2DM control subjects (n = 64 women and 29 men) who had a mean (+/-SD) age of 60.6 +/- 17.1 y and body mass index of 29.6 +/- 3.0. All participants self-reported being of African American or white ancestry. Magnetic resonance imaging-derived in vivo measures of total-body AT (TAT) and its distribution, subcutaneous AT (SAT), visceral AT (VAT), and intermuscular AT (IMAT) were acquired. Linear regression models were developed for each AT compartment to adjust for important covariates of race, sex, age, height, and weight and to examine potential interactions of covariates. RESULTS These models showed significantly less SAT (African American: -1.2 kg; white: -2.4 kg; both P = 0.001), including less femoral-gluteal SAT, more VAT (African American: 0.7 kg, P < 0.001; white: 1.8 kg, P = 0.007), and more IMAT (0.5 kg, P = 0.001) in the T2DM group. CONCLUSION We concluded that AT distribution is significantly altered in T2DM, ie, more VAT and IMAT--2 depots known to exacerbate insulin resistance--and less SAT in persons with T2DM than in healthy control subjects, a novel finding that we posit may compound the risk of insulin resistance.

Body composition in children and adults by air displacement plethysmography

Objectives: Air displacement plethysmography (ADP) may provide a partial alternative to body density (Bd) and therefore body composition measurement compared to conventional hydrodensitometry (Hd) in children. As there are no evaluation studies of ADP in children, this study had a two-fold objective: to compare Bd estimates by ADP and Hd; and to compare fat estimates by both ADP and Hd to fat estimates by another reference method, dual energy X-ray absorptiometry (DXA).Setting: Obesity Research Center, St. Luke’s/Roosevelt Hospital, New York, USA.Subjects: One hundred and twenty subjects (66 females/54 males) who ranged in age from 6–86 y and in body mass index (BMI, kg/m2) from 14.1–40.0  kg/m2 met study entry criteria.Study Design: Cross-sectional study of healthy children (age≤19 y) and adult group for comparison to earlier studies. Each subject completed ADP, Hd, and DXA studies on the same day. Only subjects with subjectively-judged successful Hd studies were entered into the study cohort.Results: There was a high correlation between Bd by ADP and Hd (Bd Hd=0.11+0.896×Bd ADP; r=0.93, SEE=0.008 g/cm3, P<0.0001), although the regression line slope and intercept differed significantly from 1 and 0, respectively. Additional analyses localized a small-magnitude Bd bias in the child (n=48) subgroup. Both ADP and Hd%fat estimates were highly correlated (r>0.9, P<0.0001) with%fat by DXA in child and adult subgroups. Bland–Altman analyses revealed no significant%fat bias by either ADP or Hd vs DXA in either children or adults, although a bias trend (P=0.11) was detected in the child subgroup.Conclusion: With additional refinements, the air displacement plethysmography system has the potential of providing an accurate and practical method of quantifying body fat in children as it now does in adults.Sponsorship: This study was in-part supported by NIH Grants RR00645, NIDDK 42618 and NIDDK 37352.

Depression Score Predicts Weight Loss following Roux-en-Y Gastric Bypass

Background: The prevalence of obesity is increasing in the United States. Bariatric surgery is the only intervention that can reliably induce and maintain significant weight loss in obese patients. The association between pre-surgical severity of depression and success at weight loss following Roux-en-Y gastric bypass (RYGBP) has not yet been fully elucidated. Methods: 145 charts of patients who underwent RYGBP for morbid obesity were reviewed. 47 patients who filled out the Beck Depression Inventory (BDI) before surgery and completed 1 year of follow-up were studied. The relationship between pre-surgical severity of depression and success at weight loss was examined through multivariate regression analysis using percent excess weight loss (%EWL) as a dependent variable and BDI score as one of the predictors. Results: Weight loss at 1 year was significantly related to the BDI score before surgery (P =0.014). BDI score was also found to be a significant predictor of the amount of weight lost (kg) 1 year after surgery (P =0.027). Age (P =0.03) and initial body mass index (BMI) (P =0.011) were the only other variables with significant independent relations to %EWL. Conclusions: Our data show a positive correlation between pre-surgical severity of depression as measured by BDI score and the 1-year success at weight loss after RYGBP as measured by %EWL. More depressed individuals tend to lose greater amounts of weight compared with less depressed individuals. Future prospective studies should examine possible mechanisms and effects of depression and other psychiatric disturbances on long-term weight loss after RYGBP.

A novel soy-based meal replacement formula for weight loss among obese individuals: a randomized controlled clinical trial.

Objective: To assess the efficacy and safety of a low calorie soy-based meal replacement program for the treatment of obesity.Design: A 12-week prospective randomized controlled clinical trial.Setting: Outpatient weight control research unit.Subjects: One hundred obese (28<BMI≤41 kg/m2) volunteers between the ages of 35 and 65 y. Seventy-four participants completed the trial.Interventions: Participants were randomized to either the meal replacement treatment group (n=50; 240 g/day, 1200 kcal/day) or control group (n=50). Both groups at baseline received a single dietary counseling session and a pamphlet describing weight loss practices.Main outcome measures: Weight, body fat, serum lipid concentrations.Results: By intent-to-treat analysis, the treatment group lost significantly more weight than the control group (7.00 vs 2.90 kg; P<0.001) and had a greater change in total (22.5 vs 6.8 mg/dl; P=0.013) and LDL cholesterol (21.2 vs 7.1 mg/dl; P<0.009). Among completers only, the treatment group again lost more weight (7.1 kg; n=37 vs 2.9 kg; n=37; P=0.0001) and had a greater reduction in total cholesterol (26.1 mg/dl; n=37 vs 6.7 mg/dl; P=0.0012) and a greater change in LDL cholesterol (21.6 vs 5.5 mg/dl; P=0.0025). (For any given degree of weight loss, the reduction in LDL cholesterol was significantly greater in the treatment group.) Treatment was well tolerated and no serious side effects were detected.Conclusions: Use of this soy-based meal replacement formula was effective in lowering body weight, fat mass and in reducing LDL cholesterol beyond what could be expected given the weight lost.Sponsorship: This research was funded by Nutripharma. Dr Allison is a member of the United Soybean Boards Scientific Advisory Panel and Chair of the Research Grants Committee.

Alternative Treatments for Weight Loss: A Critical Review

Referee: Dr. Susan Yanovski, National Task force on Ptrevention and Treatment of Obesity, NIDDK, Bldg 45, RM 6AN-18B, 9000 Rockville Pike, Bethesda, MD 20892-6600. “Nontraditional” or “alternative” treatments are extremely popular, especially with respect to obesity and body composition. Although such treatments are widely used, it is not clear that these are supported by the existing data in the peer-reviewed literature. Herein, we review the data on 18 methods/products advocated as potential anti-obesity/fat-reducing agents. We have found that none have been convincingly demonstrated to be safe and effective in two or more peer-reviewed publications of randomized double-blind placebo-controlled trials conducted by at least two independent laboratories. Nevertheless, some have plausible mechanisms of action and encouraging preliminary data that are sufficiently provocative to merit further research.

Intermuscular adipose tissue rivals visceral adipose tissue in independent associations with cardiovascular risk

Background:The metabolic implications of intermuscular adipose tissue (IMAT) are poorly understood compared to those of visceral adipose tissue (VAT) even though the absolute quantities of both depots are similar in many individuals.Objective:The aim was to determine the independent relationship between whole-body IMAT and cardiovascular risk factor parameters.Design:Whole body magnetic resonance imaging (MRI) was used to quantify total skeletal muscle (SM), total adipose tissue (TAT) of which IMAT, defined as the AT visible by MRI within the boundary of the muscle fascia, is a sub-component. Fasting serum measures (n=262) of glucose, total cholesterol (T-Chol), high-density lipoprotein cholesterol (HDL-Chol), triglycerides (TG), protein bound glucose (PBG, n=206) and insulin (n=119) were acquired in healthy African-American (AA, n=78) and Caucasian (Ca, n=109) women (body mass index (BMI) 26.5±5.7 kg/m2; 44.4±16.4 years) and men (39 AA, 62 Ca; BMI 25.6±3.5 kg/m2; 45.6±17.4 years). General linear models identified the independent effects of IMAT after covarying for SM, VAT, TAT, race, sex and two-way interactions.Results:Significant independent associations were observed for IMAT with glucose (P<0.001), PBG (P<0.001) and T-Chol (P<0.05). The association of IMAT with cholesterol differed by race in such a manner that for a unit increase in IMAT, T-Chol increased more rapidly in Ca compared to AA (P<0.05). TG, HDL-Chol and insulin had no independent association with IMAT.Conclusion:The strong independent associations of IMAT with fasting glucose and PBG suggest that IMAT may be related to glucose metabolism; however, IMAT is also associated with T-Chol in Ca.

Self-help weight loss versus a structured commercial program after 26 weeks: a randomized controlled study.

PURPOSE There have been few randomized controlled trials of commercial weight-loss programs. This ongoing study compares the effects of a self-help program and a commercial program on weight loss and other measures of obesity in overweight and obese men and women. SUBJECTS AND METHODS We report the results of the first 26 weeks of a multicenter, randomized, 2-year study of 423 subjects who had a body mass index of 27 to 40 kg/m(2). Subjects were randomly assigned to either a self-help program, consisting of two 20-minute sessions with a nutritionist and provision of printed materials and other self-help resources, or to attendance at meetings of a commercial program (Weight Watchers). Outcome measures were changes in body weight, body mass index, waist circumference, and body fat. Changes in serum homocysteine levels were measured in a subsample of participants during the first 12 weeks. RESULTS After 26 weeks, subjects in the commercial program, as compared with those in the self-help program, had greater decreases in body weight [mean (+/- SD) -4.8+/-5.6 vs -1.4+/-4.7 kg] and body mass index (-1.7+/-1.9 vs -0.5+/-1.6 kg/m(2), both P<0.001) in intention-to-treat analyses. Among subjects measured at week 26, mean waist circumference (-4.3+/-10.5 vs -0.7+/-12.7 cm) and fat mass (-3.8 +/-7.0 vs -1.5+/-7.6 kg, both P<0.05) also decreased more among subjects in the commercial program. Mean serum homocysteine levels improved in the commercial program compared with self-help (-0.5+/-1.3 vs 0.9+/-1.8 microM, P<0.05). CONCLUSIONS A structured commercial weight-loss program is more likely to be effective for managing moderately overweight patients than brief counseling and self-help.

Visceral adipose tissue: relationships between single slice areas at different locations and obesity-related health risks

Background:Visceral adipose tissue (VAT) is widely recognized as conveying the highest health risk in humans among the currently measurable adipose tissue compartments. A recent study indicated that the traditionally measured VAT area at L4–L5 is not the VAT area with the highest correlation with total VAT volume. At present, it is unknown whether the area with the highest correlation is also the most strongly associated with obesity-related health risk.Objective:The study aim was to establish which VAT slice area(s) are most strongly associated with obesity-related health risk indicators.Design:The subjects were a convenience sample of healthy adults who completed whole-body magnetic resonance imaging (MRI) scans. The correlations, with appropriate adjustments, were examined between individual MRI slice VAT areas and fasting serum/plasma triglycerides (TG), high-density lipoprotein cholesterol (HDL), glucose, insulin and blood pressure.Results:The sample consisted of 283 healthy men (age (mean±s.d.) 41.9±15.8 years; BMI, 26.0±3.2 kg/m2; VAT, 2.7±1.8 L) and 411 women (age, 48.1±18.7 years; BMI 27.0±5.4 kg/m2; VAT, 1.7±1.2 L). After adjusting for age, race, menopause status, scan position and specific blood analysis laboratory, VAT area at L4–L5 had lower correlations with most metabolic risk factors including serum/plasma TG, HDL, glucose, insulin and blood pressure than VAT volume in both men and women. The VAT areas 10 and 15 cm above L4–L5 in men had higher or equal correlations with health risk measures than VAT volume. In women, the VAT area 5 cm above or below L4–L5 and total VAT volume had similar correlations with health risk measures.Conclusions:An appropriately selected single slice VAT area is an equally reliable phenotypic marker of obesity-related health risk as total VAT volume. However, in both men and women the VAT slice area at the traditional L4–L5 level is not the best marker of obesity-related health risk.