Photograph: Getty Images; Collage: Gabe Conte

When it comes to our longevity, there’s an age-old question of nature versus nurture: Are we destined for the path that’s been laid out by our DNA? Or do our everyday choices—what we eat, how we move, and who we allow to cause us stress—play a more significant role? A growing body of research suggests that while genetics may predispose us to certain diseases, adopting healthy habits can help mitigate risks in some cases, even potentially altering how our genes express themselves (a growing field of study in longevity called epigenetics"). According to a 2016 review, genetic factors only contribute 20 to 30 percent to the variations observed in the life spans of identical twins. Lifestyle and environment dictate the rest.

Most of the traits related to longevity and health span are complex, says Bartek Nogal, PhD, principal scientist at InsideTracker, which leverages bloodwork and DNA analysis to craft personalized health plans. According to him, how long we live and how well we live when we're alive are not dictated by one gene—it’s usually hundreds, thousands, or even millions of different genetic variations. So it’s not as simple as: “If you have X gene, you’ll get Y disease.” And just because you have a family history of a disease doesn’t mean that genetics will prevail, says Gary Small, MD, chair of psychiatry at Hackensack Meridian Health, renowned for his extensive research and publications on brain health.

This conversation gained mainstream attention in 2022 when Chris Hemsworth revealed his genetic predisposition to Alzheimer’s, marked by two copies of the APOE4 gene. This condition affects two to three percent of the population and significantly increases Alzheimer’s risk. After this revelation, Hemsworth shifted his focus to healthy living, as discussed in his show Limitless. Studies indicate that diet, exercise, and stress management may affect our health, potentially altering the expression of genes associated with disease risk.

Dr. Small has researched Alzheimer's for decades, and back in the '90s, he was studying patients with Alzheimer’s when he came upon a set of identical twins with the same exact genetic makeup. “One had Alzheimer's, the other one did not,” he says. “And it was quite striking that the twin who developed the disease had a dramatically different lifestyle—[one that included smoking, drinking, an unhealthy diet, and lack of sleep]—than the one who was spared.” In a more recent study through UCLA, Dr. Small’s team performed brain scans of people with major genetic risk for Alzheimer's and found that those who had less Alzheimer's in the brain maintained a healthier lifestyle, which was defined by the study as a lower body mass index, a higher rate of exercise, and following a Mediterranean diet.

Many times in traditional healthcare, conditions aren’t caught until someone is already experiencing symptoms. The good news is that—with apps like InsideTracker, longevity clinics, and full-body scans like the Kim Kardashian-approved Prenuvo—we have more access to personalized health insights than ever before. Preventative tests can catch potential conditions before they become a problem. “It’s important to know where you stand,” says Nogal. “Look at some of your negative results and see them as opportunities to improve.” Plus, this knowledge can be lifesaving if you have a condition like high cholesterol or high blood pressure. “Taking the right medicine is going to make a big difference in your life expectancy,” says Dr. Small.

While this information can be empowering to many, there are also adverse effects, warns Dr. Small. An overload of information can cause anxiety, especially if you don’t have an expert to interpret your test results. If you take a preventative health or DNA test, you need to be prepared for some undesirable results. "Talk to your doctor about whether testing makes sense and listen to their explanation,” Dr. Small recommends. Then, ask yourself if—and how—the information will benefit you. Will you change your course of treatment or adjust your lifestyle? “It’s hard to change habits,” he says. So, lifestyle interventions are going to take a lot of discipline.

Genetics play an incredibly large role in how we live and the chronic diseases we may experience. Yet, it does seem that physical exercise, mental stimulation, stress management, sleep, and nutrition, says Dr. Small, can play a role in mitigating these risks. Both experts also underscore the importance of social connections in promoting a longer, healthier life. But if we don’t fully acknowledge the role our actions play, we’re less likely to engage in behaviors that are beneficial for our overall health and longevity. So, the best bet you have to “beat your genetics” is to form good habits and stick to them daily—and when in doubt, talk to a doc who can guide you with their expertise.

Originally Appeared on GQ