Changes in eating behaviors and body weight in Koreans: the Healthy Twin Study.

OBJECTIVE: We examined the associations between eating behavior at baseline and changes in eating behaviors with weight change, and quantified the contribution of eating behavior and genetic effects on weight change. METHODS: A prospective study of male (n = 482) and female (n = 879) Korean twins and family members who were weighed and assessed twice (baseline visit from December 2005 to December 2008, follow-up visit 2.7 ± 0.9 y later) using eating behavior subscales (external, emotional, and restrained eating) as measured by the Dutch Eating Behavior Questionnaire. RESULTS: After adjusting for family variables, eating behavior subscales at baseline, changes in emotional and restrained eating, age, education, weight, and lifestyle at baseline, and menopausal status at baseline (for women), an increase in external eating was significantly associated with weight gain in men (1.08, 95% confidence interval 0.41-1.74) and in women (0.63, 95% confidence interval 0.13-1.12). None of the three eating behavior subscales at baseline or changes in emotional and restrained eating were associated with weight change. Eating behavior at baseline and changes in those eating behaviors accounted for 4% and 1% of the changes in weight in men and women, respectively. Additive genetic effects in women contributed to 18% of weight change, whereas in men there was no genetic contribution. CONCLUSIONS: These results suggest that an increase in external eating may predict adult weight gain in men and women. However, the relative contribution of eating behavior to weight change was very small, whereas the contribution of genetic effects on weight change was significant in women.

Analysis of mannose-binding lectin 2 (MBL2) genotype and the serum protein levels in the Korean population.

Mannose-binding lectin (MBL) is a C-type lectin produced by the liver and involved in the innate immune response. We have analyzed six SNPs of MBL2 gene--three at promoter (-550, -435, and -221), one at 5'-untranslational region (UTR) (+4), and two at coding (Gly54Asp and Leu126Leu) regions--in the Korean population (N=129), and have correlated genotypes with the serum concentration and functional characteristics. Of those, the Asp54 allele (P<10(-15)), L allele at -550 (P<10(-7)), and P allele at +4 (P=0.012) were correlated with low MBL levels. The effect of the X allele at -221 on MBL levels in the Korean population appeared to be less profound than that of other populations. The highest MBL producing promoter haplotype in the Korean population was HYP, followed by LYQ and LYP, and then LXP. From functional analysis of MBL, low MBL levels were correlated with low mannan-binding, low C4 complement activation, and lack of high ordered oligomers. Our results support that the promoter and coding polymorphisms of MBL are correlated with its functional activity as well as circulating levels, and the association patterns are quite similar to those of other populations.