Dietary Restraint Is Non-Genetically Associated with Change in Body Mass Index: The Healthy Twin Study

PURPOSE: We aimed to examine if past and more recent body mass index (BMI) changes are associated with eating behavior (EB) traits and whether these associations are due to non-genetic factors. MATERIALS AND METHODS: In 1321 Korean twins and family members, recent and past BMI change groups were defined using quartiles of BMI change between first and second visits over 2.4+/-0.9 years and BMI change between 20 years old and second visit, respectively. We applied linear mixed analysis for relationships of past or recent BMI change groups and each EB (restrained, external, and emotional EB using the Dutch Eating Behavior Questionnaire) assessed at second visit after adjusting for household effect and covariates (age, gender, education, medical history of diabetes, hypertension, and dyslipidemia, alcohol use, physical activity, smoking habit, and calorie intake). In monozygotic twin pairs, paired t-test for within-pair comparison and conditional logistic regression analysis were conducted regarding EB. RESULTS: Greater past BMI change was associated with higher restrained eating scores (P for trend=0.031), whereas greater recent BMI change was associated with higher external eating scores (P for trend=0.046). In co-twin-control analysis, twins with greater past BMI change were more likely to have higher restrained eating scores as compared with their co-twins with lower past BMI change (odds ratio 1.80; 95% confidence interval 1.13-2.87), whereas there were no associations between recent BMI change and external eating scores. CONCLUSION: Greater BMI change since 20 years old is associated with higher dietary restraint, and non-genetic factors explain this relationship.

Effect of Body Mass Index Change on Cardiovascular Risk Factors in Korean Men

BACKGROUND: Obesity is becoming an increasing public health problem. Weight gain in adults causes increased risk of cardiovascular diseases and mortality. The aim of the present study was to investigate the effect of body mass index (BMI) change on cardiovascular risk factors in Korean men. METHODS: This study subjects consisted of 1,169 people, aged 20~71 y at baseline year who had undergone health examinations 2 times for average 8-year period. Height, weight, systolic and diastolic blood pressure, total cholesterol, triglyceride, HDL-C, fasting plasma glucose, and urate were measured. Smoking status, alcohol drinking, and exercise were assessed through self-questionnaire. RESULTS: The baseline mean age was 43.1 6.7 year, the mean weight was 66.8+/-5.2 kg, and the mean BMI was 23.3+/-2.5kg/m2. BMI significantly increased by 0.9 0.04 kg/m2 the during 8-year period. An increase of 1 kg/m2 in BMI was significantly associated with increase of blood pressure, total cholesterol, triglyceride, LDL-C, and urate, and decrease of HDL-C. The risk of cardiovascular diseases was increased with more weight gain. Compared with the lowest quintile of BMI change, the adjusted relative risk of the highest quintile of BMI change for hypercholesterolemia, hypertriglyceridemia, low HDL-C, and hyperuricemia were 5.59 (95% CI: 1.19~26.36), 3.24 (95% CI: 1.53~6.88), 5.16 (95% CI: 2.27~11.77), and 2.18 (95% CI: 1.17~4.06), respectively. The adjusted relative risk for cardiovascular disease tended to increase according to BMI increase (P for trend<0.0001). CONCLUSION: The increase of BMI was significantly associated with worsening of cardiovascular risk factors in Korean men.