Sitting most of the day? Eating poorly? Not sleeping well? Stressed out? These behaviors could be affecting your health—and your DNA.
Think of your body like a car. Sometimes you drive too fast, scrape against a curb or neglect to change your oil at the scheduled time. This behavior may result in minor cosmetic or mechanical “dings” to your car. The environment you drive in, including harsh weather, pothole-littered roads and crowded parking lots may, through no fault of your own, also result in damage to your car. Think about it: How many behaviorally or environmentally caused dings does your car have?
Now, can your environment and behaviors cause analogous dings to your DNA that alter your cancer risk? You are born with your DNA, so it is not something you can change, but you may be able to modify it in important ways. Research shows that through your behavior and environment, your DNA collects imperfections, some of which you may be able to repair through healthy behavior.
In more scientific language, there are epigenetic modifications that do not change the DNA sequence but are layered on top and alter gene expression and protein levels to produce positive and negative impacts on your health. Harmful protein levels may be the result of these dings to your DNA: added negatively acting epigenetic modifications or removed beneficial ones. Protein levels are important, as too much of some or too little of others may cause cells to behave improperly. These imbalances and subsequent cellular behaviors are something researchers are exploring as possible causes for cancer and a variety of other diseases.
Some of your epigenetic modifications (good and bad) may be inherited and perhaps this is part of the reason why cancer, heart disease and Alzheimer’s often run in certain families. As you can imagine, there is great interest in whether and exactly how environment or lifestyle choices such as diet, exercise, sleep and stress levels impact our disease risk. High-fat diets, for example, are fairly consistently associated with cancer, and often with more aggressive cases. Evidence exists suggesting that certain fat by-products impact protein expression in specific pathways related to cancer development. It is possible that high-fat diets epigenetically alter your DNA in a negative fashion leading to cancer – the “you are what you eat” adage may be more prophetic than we thought.
The good news is that just as you can take your car in to get some of the dings cleaned up, you can likely alter your DNA in positive ways through good epigenetic modifications. It may be possible, for example, to exercise regularly or eat certain foods and mitigate some inherited or lifetime-incurred epigenetic modifications. For those of us interested in gene-environment interactions, this is an opportunity to explore how lifestyles and environments modify health through molecular-level DNA alterations. Understanding which of these “dings” cause disease and how we can reduce them will allow us to connect behaviors and environment to their biological manifestations and ultimately reduce disease risk.
Ingrid Oakley-Girvan, PhD, MPH, is a research scientist at the Cancer Prevention Institute of California and a member of the Stanford Cancer Institute. Watch Ingrid’s video on Door Dings and DNA here.