Researchers from the University of Washington have demonstrated that regular physical activity can alter how genes are expressed in identical twins. The findings appeared in a peer reviewed journal focused on scientific evidence and biology.
In a long term study, scientists collected DNA samples from seventy pairs of identical twins at multiple points between 2012 and 2019. Participants wore fitness trackers to quantify physical activity, completed questionnaires, and provided measurements for waist circumference and body mass index. This combination of objective and self reported data allowed a precise look at how movement correlates with genetic activity over time.
Across the paired twins, the sibling with higher weekly activity levels—calculated at about 150 minutes or more—tended to show a smaller waistline and a lower BMI compared with their less active twin. Beyond these physical indicators, researchers observed changes in the activity of more than fifty genes that scientists have linked to reduced risk for metabolic diseases, including stroke, type 2 diabetes, and cardiovascular conditions. These gene activity shifts suggest a potential mechanism by which lifestyle choices can influence disease risk at a molecular level.
Prior research into identical twins has shown that many diseases emerge with age, and many of these differences reflect epigenetic modifications—changes in gene expression driven by lifestyle and environment rather than changes to the underlying DNA sequence. Since identical twins start with the same genetic blueprint, they serve as a natural comparison to understand how behavior and surroundings can steer biological outcomes. This study adds to a growing body of evidence that activity patterns can leave lasting epigenetic marks, linking daily habits to long term health trajectories in a very tangible way. (University of Washington, 2022 2023)