Rebecca S. Reeves

Reduction in weight and cardiovascular disease risk factors in individuals with type 2 diabetes: one-year results of the look AHEAD trial.

OBJECTIVE—The effectiveness of intentional weight loss in reducing cardiovascular disease (CVD) events in type 2 diabetes is unknown. This report describes 1-year changes in CVD risk factors in a trial designed to examine the long-term effects of an intensive lifestyle intervention on the incidence of major CVD events. RESEARCH DESIGN AND METHODS—This study consisted of a multicentered, randomized, controlled trial of 5,145 individuals with type 2 diabetes, aged 45–74 years, with BMI >25 kg/m2 (>27 kg/m2 if taking insulin). An intensive lifestyle intervention (ILI) involving group and individual meetings to achieve and maintain weight loss through decreased caloric intake and increased physical activity was compared with a diabetes support and education (DSE) condition. RESULTS—Participants assigned to ILI lost an average 8.6% of their initial weight vs. 0.7% in DSE group (P < 0.001). Mean fitness increased in ILI by 20.9 vs. 5.8% in DSE (P < 0.001). A greater proportion of ILI participants had reductions in diabetes, hypertension, and lipid-lowering medicines. Mean A1C dropped from 7.3 to 6.6% in ILI (P < 0.001) vs. from 7.3 to 7.2% in DSE. Systolic and diastolic pressure, triglycerides, HDL cholesterol, and urine albumin-to-creatinine ratio improved significantly more in ILI than DSE participants (all P < 0.01). CONCLUSIONS—At 1 year, ILI resulted in clinically significant weight loss in people with type 2 diabetes. This was associated with improved diabetes control and CVD risk factors and reduced medicine use in ILI versus DSE. Continued intervention and follow-up will determine whether these changes are maintained and will reduce CVD risk.

State of the Evidence Regarding Behavior Change Theories and Strategies in Nutrition Counseling to Facilitate Health and Food Behavior Change

Behavior change theories and models, validated within the field of dietetics, offer systematic explanations for nutrition-related behavior change. They are integral to the nutrition care process, guiding nutrition assessment, intervention, and outcome evaluation. The American Dietetic Association Evidence Analysis Library Nutrition Counseling Workgroup conducted a systematic review of peer-reviewed literature related to behavior change theories and strategies used in nutrition counseling. Two hundred fourteen articles were reviewed between July 2007 and March 2008, and 87 studies met the inclusion criteria. The workgroup systematically evaluated these articles and formulated conclusion statements and grades based upon the available evidence. Strong evidence exists to support the use of a combination of behavioral theory and cognitive behavioral theory, the foundation for cognitive behavioral therapy (CBT), in facilitating modification of targeted dietary habits, weight, and cardiovascular and diabetes risk factors. Evidence is particularly strong in patients with type 2 diabetes receiving intensive, intermediate-duration (6 to 12 months) CBT, and long-term (>12 months duration) CBT targeting prevention or delay in onset of type 2 diabetes and hypertension. Few studies have assessed the application of the transtheoretical model on nutrition-related behavior change. Little research was available documenting the effectiveness of nutrition counseling utilizing social cognitive theory. Motivational interviewing was shown to be a highly effective counseling strategy, particularly when combined with CBT. Strong evidence substantiates the effectiveness of self-monitoring and meal replacements and/or structured meal plans. Compelling evidence exists to demonstrate that financial reward strategies are not effective. Goal setting, problem solving, and social support are effective strategies, but additional research is needed in more diverse populations. Routine documentation and evaluation of the effectiveness of behavior change theories and models applied to nutrition care interventions are recommended.

Comparison of 2-Year Weight Loss Trends in Behavioral Treatments of Obesity: Diet, Exercise, and Combination Interventions

OBJECTIVE The effects of three cognitive-behavioral weight control interventions for adults were compared: diet only, exercise only, and a combination of diet and exercise. This article reports 2-year follow-up data. DESIGN The three interventions were compared in a randomized, experimental design. SUBJECTS A total of 127 men and women who were at least 14 kg overweight (according to height-weight tables) were recruited from an urban community and assigned randomly to the experimental conditions. INTERVENTION The dietary intervention was a low-energy eating plan adjusted to produce a 1 kg/week loss of weight. The exercise component involved training in walking and a home-based program of up to five exercise periods per week. There were 12 weekly instructional sessions, followed by 3 biweekly and 8 monthly meetings. All sessions were led by registered dietitians. OUTCOME MEASURES Changes in body weight. STATISTICAL ANALYSES Analysis of variance for weight changes and repeated measures analysis of variance for weight change trends. RESULTS At 1 year, no significant differences were noted among the three groups. The diet-only group lost 6.8 kg, the exercise-only group lost 2.9 kg, and the combination group lost 8.9 kg (P=.09). During the second year, the diet-only group regained weight--reaching 0.9 kg above baseline; the combination group regained to 2.2 kg below baseline; and the exercise-only group regained slightly to 2.7 kg below baseline (P=.36). Repeated measures analysis of variance showed a group-by-time interaction (P=.001); data for the dieting groups best fit a U-shaped regain curve (P=.001). APPLICATIONS The results suggest that dieting is associated with weight loss followed by regain after treatment ends, whereas exercise alone produced smaller weight losses but better maintenance. The large outcome variability and unequal difficulty of the regimens across groups limit the generalizability of the findings.

Nondieting Versus Dieting Treatment for Overweight Binge-Eating Women

This study evaluated the effectiveness of nondieting versus dieting treatments for overweight, binge-eating women. Participants (N = 219) were randomly assigned to 1 of 3 groups: diet treatment (DT), nondiet treatment (NDT), or wait-list control (WLC). DT received a balanced-deficit diet reinforced with behavioral strategies. NDT received therapy designed to help participants break out of their dieting cycles. Treatment in both conditions was administered in weekly groups for 6 months, followed by 26 biweekly maintenance meetings, for a total of 18 months of contact. At 6 months posttreatment, DT lost 0.6 kg while NDT gained 1.3 kg. Both treatment groups reduced their Binge Eating Scale scores significantly more than WLC. At 18-month follow-up, both treatment groups experienced weight gain but maintained similar reductions in binge eating. Results indicate that neither intervention was successful in producing short- or long-term weight loss. Therapist biases, which may have affected treatment integrity, and other methodological issues are discussed in relation to the small weight losses achieved.

Weight loss in overweight Mexican American children: a randomized, controlled trial.

OBJECTIVES. Childhood overweight has increased significantly in the past 20 years, with the highest rates noted among Mexican Americans. Although this minority group is in significant need of intervention, few programs have demonstrated actual decreases in weight. In this study we evaluated an intensive healthy lifestyle program designed to result in weight reduction for overweight Mexican American children. We hypothesized that children randomly assigned to an intensive intervention would significantly reduce their standardized BMI when compared with children randomly assigned to a self-help condition. PATIENTS AND METHODS. A total of 60 children (33 boys; 55%) between the ages of 10 and 14 years at or above the 85th percentile for BMI were randomly assigned to a 6-month intensive-intervention or self-help condition. RESULTS. Children in the intensive-intervention condition significantly reduced their standardized BMI when compared with the children in the self-help condition. The change in standardized BMI was significantly different at both 3 and 6 months, with intensive-intervention participants showing greater decreases in weight. CONCLUSIONS. Overall, the results were promising, suggesting that an intensive, individualized intervention may be an effective means for promoting weight loss in overweight Mexican American children.

Action for Health in Diabetes (Look AHEAD) Trial: Baseline Evaluation of Selected Nutrients and Food Group Intake

BACKGROUND Little has been reported regarding food and nutrient intake in individuals diagnosed with type 2 diabetes, and most reports have been based on findings in select groups or individuals who self-reported having diabetes. OBJECTIVE To describe the baseline food and nutrient intake of the Look AHEAD (Action for Health in Diabetes) trial participants, compare participant intake to national guidelines, and describe demographic and health characteristics associated with food group consumption. METHODS The Look AHEAD trial is evaluating the effects of a lifestyle intervention (calorie control and increased physical activity for weight loss) compared with diabetes support and education on long-term cardiovascular and other health outcomes. Participants are 45 to 75 years old, overweight or obese (body mass index [BMI] > or = 25), and have type 2 diabetes. In this cross-sectional analysis, baseline food consumption was assessed by food frequency questionnaire from 2,757 participants between September 2000 and December 2003. STATISTICAL ANALYSIS Descriptive statistics were used to summarize intake by demographic characteristics. Kruskal-Wallis tests assessed univariate effects of characteristics on consumption. Multiple linear regression models assessed factors predictive of intake. Least square estimates were based on final models, and logistic regression determined factors predictive of recommended intake. RESULTS Ninety-three percent of the participants exceeded the recommended percentage of calories from fat, 85% exceeded the saturated fat recommendation, and 92% consumed too much sodium. Also, fewer than half met the minimum recommended servings of fruit, vegetables, dairy, and grains. CONCLUSIONS These participants with pre-existing diabetes did not meet recommended food and nutrition guidelines. These overweight adults diagnosed with diabetes are exceeding recommended intake of fat, saturated fats, and sodium, which may contribute to increasing their risk of cardiovascular disease and other chronic diseases.

Evaluation of a culturally appropriate intervention to increase physical activity.

OBJECTIVE To evaluate a culturally appropriate intervention to increase activity in overweight Mexican American women. METHODS Participants were randomly assigned to a physical activity program or wait-list control. RESULTS Treated participants were not more active than controls at 6 or 12 months. In addition, we found no significant differences in the proportion of individuals who met an objective criterion for physical activity from baseline to 6 months in the treatment or control groups. CONCLUSION The intervention did not increase physical activity in this population. Differences in baseline activity and contamination of the control group may partially account for the outcome.

Effect of alcohol dose on plasma lipoprotein subfractions and lipolytic enzyme activity in active and inactive men

Controversy as to which lipoprotein subfraction of high-density lipoprotein (HDL) increases during alcohol consumption prompted the current study of the effects of two alcohol doses over varying time intervals on plasma lipoproteins and lipolytic enzymes. Measurements were made in 49 healthy men before and after three weeks of abstinence from alcohol and after consumption of one or three 12-ounce cans of beer per day. We found that HDL (10%), HDL2 (14%), and HDL3 (9%) cholesterol, and apolipoprotein A-I (7%) decreased with abstinence from alcohol and then increased with its consumption. These increases were not significant until after 3 weeks of daily alcohol intake, but they were significant in both the one-can and three-cans of beer per day groups. In the 23 inactive subjects HDL and HDL2 cholesterol decreased with abstinence but did not increase significantly with alcohol intake. Lipolytic enzymes were not changed by alcohol manipulation, but the level of lipoprotein lipase was higher and that of hepatic lipase was lower at each measurement point in the 26 habitually active versus the 23 inactive subjects. Adjustment for weight or skinfold thickness did not affect lipoprotein changes over time within groups but did eliminate many of the differences between activity groups. Alcohol consumption seems to be related to possibly beneficial influences on plasma HDL and HDL2 cholesterol, and may thus impact the risk of heart disease.

Nutrient intake of obese female binge eaters.

OBJECTIVE To compare the 6-month change in selected nutrients and number of binge days (from 7-day food records) between obese binge eaters randomly assigned to either a behavioral self-management (BSM) or waiting list control (WLC) group. Within each of the 2 groups, the average intake of selected nutrients on binge and nonbinge days at baseline and at 6 months were compared. DESIGN A randomized, controlled, intervention study with assessments at entry and 6 months later. SUBJECTS Forty-six women in the BSM group and 36 in the WLC group completed the 6-month measurement. Participants were 25 to 50 years of age, 30 to 90 pounds overweight, did not have a history of physical or psychological illnesses, and scored 20 or greater on the binge eating scale. INTERVENTION Participants in the BSM intervention received 6 months of weekly, 1-hour classes taught by registered dietitians. Participants in the WLC group were not contacted during the 6 months. OUTCOME MEASURES The main outcome measures were change in energy consumed (kilocalories); percentage of energy from fat, protein, and carbohydrate; grams of fiber/1,000 kcal; and change in the number of self-reported binge days. STATISTICAL ANALYSES Weight at 6 months was compared using a 2-sample t test. The change in the number of binge days at 6 months and the amount of change in selected nutrients by group was compared using the 2-sample t test. The paired t test was used to compare the average nutrient intakes on binge and nonbinge days within groups. RESULTS No significant difference was found in the 6-month change between groups in any of the selected nutrients. The BSM group reported a greater reduction in binge days between baseline and 6 months compared with the WLC group (mean 1.0 vs 1.7, P < 0.03). Within the BSM group at 6 months, energy intake and percentage of energy from fat on nonbinge days were significantly reduced compared with binge days. At baseline within the WLC group, energy intake increased and percentage of energy from protein decreased significantly on nonbinge days compared with binge days. Within the WLC group at 6 months, energy intake and percentage of energy from fat significantly decreased and percentage of energy from protein significantly increased on nonbinge days. CONCLUSIONS Our results suggest that collecting dietary information from participants identified with binge eating disorder is challenging. Dietitians who conduct behavioral weight management programs may require additional training in identifying and understanding the psychological characteristics of participants with binge-eating disorder.

Rise of Plasma Ghrelin With Weight Loss is Not Sustained During Weight Maintenance

Objective: Ghrelin is postulated to be an orexigenic signal that promotes weight regain after weight loss (WL). However, it is not known whether this putative effect of ghrelin is sustained after weight stabilization. The objective of this study was to investigate the relationship of plasma ghrelin concentrations to active WL and weight maintenance in obese subjects.