Is BMI Heritable? A recent study published in the Jama Network suggests that obesity in adolescence can have long-lasting effects on future generations. The study, which investigated the heritability of body mass index (BMI) across generations within families, found that children born to parents who were obese at age 17 had a 77% greater likelihood of developing obesity at the same age.
Parental Influence on Offspring Health: According to the researchers, the weight status of parents at 17 years of age was strongly associated with the obesity risk for their offspring, regardless of gender. This highlights the significant impact parental factors can have on the health outcomes of the next generation.
Research Methodology and Findings: The study, conducted using data from mandatory medical screenings before compulsory military service in Israel, analyzed the BMI of 447,883 adolescents at age 17 and compared it with that of their parents at the same age. Children with both parents being obese during their teen years faced an elevated risk of developing obesity themselves. Meanwhile, offspring of parents who were severely underweight at age 17 had a much lower probability of being obese at the same age.
Genetic Influence on Obesity: The researchers noted a significant correlation of 0.386 between mid-parental and offspring BMI, indicating a moderate association. The estimation of narrow-sense heritability for the additive genetic variance in BMI was determined to be 39%. Additionally, daughters were found to be more susceptible to obesity compared to sons, even when only the mother had a history of obesity as a teen.
Implications and Future Research: The findings of this study provide valuable insights into how genetics play a role in body weight during adolescence. By establishing the links between parental and offspring obesity, particularly during late adolescence, the researchers hope to further understand the early origins of obesity and develop preventive strategies to address this pressing health concern.