Effects of Cognitive-Behavioral Treatment for Weight Loss in Family Members

Abstract

The possibility that lifestyle changes may be shared by the family members of subjects with obesity attending cognitive-behavioral treatment (CBT) for weight loss has been scarcely evaluated. The purpose of this study was to measure the changes in body weight, lifestyle habits, and stage of change toward physical activity in the family members of 149 subjects with overweight/obesity enrolled into a weekly group CBT for weight management in the years 2007-2008. 230 adult (aged >18 years) family members (129 spouses, 72 children (43 female, 29 male), 29 with a different family relationship) completed a self-administered questionnaire at baseline and soon after the end of the completion of their relatives' program (approximately 6 months later). The questionnaire consisted of qualitative information regarding food choices, estimation of energy and food intake, self-report of height and weight, and motivation toward physical activity. At baseline, self-reported body mass index was normal in 115 cases, in the range 25 to 29.9 in 80 and ≥30 in 35. Following CBT of their relatives, the family members significantly reduced their average daily energy intake (−232 kcal/day; P<0.001) and the reported body weight decreased on average by 1 kg (P=0.001). The analysis of food choices revealed a reduced average daily amount of energy from dressings (−40 kcal, P<0.001), main courses with cheese or fat meat (−24 kcal, P=0.002), refined carbohydrates (−16 kcal, P<0.001), bread (−58 kcal, P<0.001), breakfast biscuits (−23 kcal, P=0.005), chocolate (−7 kcal, P=0.024), and nonalcoholic beverages (fruit juices and carbonated drinks; −10 kcal; P=0.013), whereas fruit consumption was increased (+10 kcal; P=0.023). There was also a shift in the stage of change toward exercising. Body mass index changes of family members and CBT subjects were significantly correlated, mainly within spouses. In conclusion, CBT for weight loss positively influences the lifestyle habits of family members of participants, reducing energy intake and promoting a more favorable attitude toward physical activity.