Maybe We’re Not Born With It

Science Fields

“If we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would have found the safest way to health.”


Quality nutrition, sleep, and physical exercise are the cornerstones of good health – physically and mentally. Sure, some of us have vulnerabilities that may leave us susceptible to certain diseases and conditions however, a newly published study draws attention to the importance of environmental factors on health. 

The study led by Washington State University Professor Dr. Glen Duncan and colleagues reveals important new insights regarding the role of exercise in gene expression or epigenetics. But what is epigenetics? “Epi-” is Greek for on or above. So, epigenetics refers to factors beyond the genetic code. Epigenetics, therefore, studies how changes at the cellular level control the activity of genes without altering the DNA. 

Dr. Duncan and the research team collected cheek swabs of 70 pairs of monozygotic (identical) twins and used fitness trackers to measure their body mass indexes as well as waistlines. The study results revealed considerable differences in the twin pairs’ exercise levels and body mass index. Moreover, the cheek swabs pointed to interesting epigenetic differences, too. The researchers found that twins who were highly physically active (defined as exercising more than 150 minutes per week) had epigenetic changes in areas called DNA methylation regions. DNA methylation is a process by which methyl groups are added to the DNA molecule without changing the sequence. These regions are known to be associated with genes that are specific to vigorous exercise and metabolic risk factors. 

Physically active siblings were at a lower risk for metabolic syndrome. According to the researchers, this condition can lead to heart disease and stroke. So, physical exercise offers quite excellent protective benefits when it comes to metabolic diseases. Now, the researchers are suggesting that exercise is affecting many cell types, as well. 

According to Washington State University biologist Dr. Michael Skinner, “If genetics and DNA sequence were the only driver for biology, then essentially twins should have the same diseases. But they don’t.” 

The results of this study carry critical importance because they suggest that we are not necessarily at the mercy of our DNA. Even if we have certain genetic vulnerabilities, we can take action to protect our health and improve wellbeing. 


  • 1. Duncan, G.E., Avery, A., Thorson, J.L.M. et al. Epigenome-wide association study of physical activity and physiological parameters in discordant monozygotic twins. Sci Rep 12, 20166 (2022). https://doi.org/10.1038/s41598-022-24642-3
  • 2. https://www.sciencedaily.com/releases/2022/12/221206083112.htm
  • 3. https://medlineplus.gov/genetics/understanding/howgeneswork/epigenome/