Gene plays the primary role in BMI and obesity transmission


Obesity, which means too much body fat, is a serious health issue. Being obese can increase the risk of many diseases.

The World Health Organization uses body mass index (BMI) to define obesity. BMI is obtained as the body mass divided by the square of the body weight. When a person’s BMI is over 30 kg/m2, s/he is thought to have obesity.

It is known that external factors, such as living environment, diet, exercise, and mood, can influence BMI and the risk of obesity.

Nevertheless, a new study shows that gene plays the dominant role in parent-child body weight transmission. In other words, an individual’s BMI is strongly impacted by his/her parents’ BMI. The finding is published in Economics & Health Biology.

In the study, researchers used 10,000+ parent-child data from the National Health Interview Survey. They compared the strength of parent-child BMI transmission and obesity in adopted children relative to biological children.

The result showed strong correlations among biological parent-child pairs. However, no significant correlation was found in adoptive parent-child pairs, even though they share the same household environment.

This indicates that gene plays a key role in intergenerational transmission of BMI and obesity.

As for the environmental factors like lifestyle, researchers suggest that these factors could be important for BMI and obesity determination, but they may be not important for BMI and obesity transmission.

Future research will directly examine genetic transmission of BMI and obesity for children facing different environment conditions. In addition, how environment change can affect genetic transmission of BMI and obesity needs to be tested.

Citation: Classen TJ, Thompson O. (2016). Genes and the Intergenerational Transmission of BMI and Obesity. Economics & Human Biology, In Press, Accepted Manuscript, Available online 23 August 2016. doi:
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