Evaluation of a Health at Every Size vs a Behavioral Weight Loss Approach for Obese Women

Comparative Health Improvements and Rate of Relapse in Weight-Centered vs. Wellness-Centered Interventions for Obese Women

For over four decades the medical literature has observed a relationship between obesity and poorer health outcomes. The causal mechanisms of these poorer outcomes however are unclear. One assumption that has been supported by correlational data is that increased weight is associated with increased cardiovascular disease (CVD) risk factors (i.e., hypertension, dyslipidemia, and type 2 diabetes). Consequently, obese people are routinely prescribed weight loss programs in order to prevent or control these conditions. Unfortunately, long term weight loss has been met with minimal success for the large majority of people. Furthermore, the data suggesting that weight loss leads to long term health benefits and decreased mortality is limited and contradictory. The purpose of the proposed project is to perform a randomized controlled pilot study comparing the effectiveness of two lifestyle interventions for preventing CVD risk factors (hypertension, dyslipidemia, and type 2 diabetes). The interventions are constitutionally similar; however, the treatment condition is a wellness-focused intervention that teaches healthy living without consideration of weight. The control condition is a traditional curriculum where the prescribed outcome is weight loss. The primary goals of both programs are to reduce hypertension and total cholesterol, and to enhance glucose control. Secondary outcomes of interest are psychological and behavioral in nature (e.g., self-esteem; depressed mood; anxiety; stress; quality of life; dietary habits; and physical activity). We will compare the trajectories of the CVD and psychological/behavioral risk factors for a total period of 24 months (including the time from baseline to the end of the 6-month intervention). Our objectives are to collect data to a) determine whether participants in both programs reduce CVD and psychological/behavioral risk factors at the completion of the 6-month program, and b) compare the persistency of health improvements and rate of relapse at the end of the 18-month follow-up period between the traditional weight loss intervention and the wellness-focused intervention.

Inclusion Criteria:

1. Women ages 30 to 45 years old (at intervention onset);
2. BMI between 30 and 45
3. Physically inactive
4. Practicing birth control if heterosexually active and pre-menopausal.
5. English speaking

Exclusion Criteria:

1. Current smoker
2. Use of medications known to affect weight/energy expenditure;
3. Pregnant, intending to get pregnant over next two years, or lactating;
4. Recent myocardial infarction (within 6 months);
5. Congestive heart failure
6. Active neoplasms
7. Type 1 and insulin-dependent Type 2 diabetes
8. Cerebrovascular disease
9. Renal disease
10. Cirrhosis
11. Bulimia nervosa
12. Alcohol and/or Substance Abuse
13. Major psychiatric disturbance (suicidality, psychosis, anti-social personality disorder, current manic episode)
14. Prior bariatric surgery
15. Plans to have bariatric surgery over next 2.5 years