Effects of self-reported calorie restriction on correlations between SIRT1 polymorphisms and body mass index and...

SIRT1 acts as a cellular sensor to detect energy availability and modulates fat and glucose metabolism. This study assessed the effects of self-reported calorie restriction (CR) and exercise on correlations between SIRT1 polymorphisms and body mass index (BMI) and long-term weight change. This cross-sectional study enrolled 4023 subjects aged 35-69years (1847 men and 2176 women) selected from participants in the Japan Multi-Institutional Collaborative Cohort Study. This study was based on a self-administered questionnaire. No significant correlations between SIRT1 polymorphisms and BMI or long-term weight change were found in either the CR or the active groups. In the no-CR group, women with the rs1467568 G allele had a higher BMI than women without (p=0.02). Moreover, women with the rs7895833 A or rs1467568 G allele gained more weight from the age of 20years than women without these alleles (p=0.03 for rs7895833 and p=0.003 for rs1467568). In addition, the odds ratios (95% confidence intervals) of these alleles for overweight (BMI >27.5kg/m²) were significantly high in the no-CR women group (1.78 (1.06-2.99) for rs7895833 and 1.88 (1.13-3.15) for rs1467568) but not in the CR group. The results of this study suggest that CR might override the genetic contributions of the SIRT1 rs7895833 A and rs1467568 G alleles to BMI and long-term weight change.