Gene-Environment Interaction Explained

Gene-Environment Interaction: The Crucial Role in Obesity

Research highlights the crucial role social and environmental factors play in obesity.

Last updated on February 20th, 2025

Gene-environment interaction (GxE) refers to the dynamic relationship between an individual’s genetic makeup and physical and social environment. This interaction factors into what determines how a person’s genes are expressed, influencing traits, diseases, and overall genetic expression.

Recently, nutrition coach and health author Thomas DeLauer illustrated the concept of GxE by examining cases of obesity in twins raised in different environments.

“Separated twins — two people with the same DNA — put into two completely separate environments. How do they fare against obesity? Does one become obese and the other not solely because of their environment?” DeLauer questioned.

Twin Obesity Research

A study examined twins with genetic mutations linked to obesity. The findings reveal that, regardless of environmental factors, these individuals were predisposed to gaining weight and becoming obese. This genetic influence accounted for 69% of cases in women and 74% in men. Dealing with obesity genes presents significant challenges, making it difficult to avoid obesity even in favorable environments.

However, if identical twins are placed in an environment that promotes unhealthy eating and encourages obesity, their chances of becoming obese could approach nearly 100%.

Gene-Environment Interaction

The human genome evolves slowly. “100 years ago, we were pretty lean as a society,” DeLauer suggested.

Today, American society faces rising obesity rates, with many individuals classified as overweight. Nearly 43% of Americans are classified as obese. It’s unlikely that genetic makeup has changed significantly in 100 years, as DNA evolves over a much longer timescale. According to DeLauer, it’s not our DNA changing; it’s our environment. The genetic predispositions for obesity likely existed a century ago, but the environmental triggers to activate them were far less prevalent.

“We didn’t have food readily available. We have an opposite problem today,” DeLauer explained. “100 years ago, it was harder to get food. Nowadays, food is everywhere. We have a crisis-of-abundance issue, not a crisis of needing food.”

Control Environment

According to DeLauer, small, unglamorous actions often make the most sense. Although these hacks may seem insignificant, they can collectively address more significant challenges. Some of the ways to control one’s environment to help prevent obesity include:

1. Avoid having access to unhealthy food where you live.
2. Intermittent fasting involves setting specific eating and fasting periods. Establishing boundaries for when and what to eat is efficient for individuals with obesity-prone genetics.
3. Move more daily. While a sedentary lifestyle can negate the benefits of exercise, incorporating regular activity throughout the day can help maintain metabolic health.
4. Consider compressing eating windows to regulate calorie intake and metabolism.

More In Research

References

1. Ottman R. (1996). Gene-environment interaction: definitions and study designs. Preventive medicine, 25(6), 764–770. https://doi.org/10.1006/pmed.1996.0117
2. Stunkard, A. J., Harris, J. R., Pedersen, N. L., & McClearn, G. E. (1990). The body-mass index of twins who have been reared apart. The New England journal of medicine, 322(21), 1483–1487. https://doi.org/10.1056/NEJM199005243222102
3. Elks, C. E., den Hoed, M., Zhao, J. H., Sharp, S. J., Wareham, N. J., Loos, R. J., & Ong, K. K. (2012). Variability in the heritability of body mass index: a systematic review and meta-regression. Frontiers in endocrinology, 3, 29. https://doi.org/10.3389/fendo.2012.00029

Conclusion:

The concept of gene-environment interaction is crucial in understanding the complex relationship between genetic and environmental factors in the development of obesity. By recognizing the impact of environmental factors on gene expression, we can better understand the role of lifestyle choices in obesity prevention and treatment. By controlling our environment, we can reduce the risk of obesity and promote overall health and well-being.

FAQs:

* What is gene-environment interaction?
Gene-environment interaction refers to the dynamic relationship between an individual’s genetic makeup and physical and social environment.
* How does gene-environment interaction affect obesity?
Gene-environment interaction can influence the development of obesity by affecting the expression of genes involved in metabolism and weight regulation.
* What are some ways to control our environment to prevent obesity?
Some ways to control our environment include avoiding unhealthy food, intermittent fasting, regular physical activity, and compressing eating windows.