Your Genes or Your Lifestyle — Which Matters Most?

by Carole Jackson, Bottom Line Health

If you’re searching for a plan to improve your cardiovascular health, then exercise and a healthy diet may be just what the doctor will order… but will it really make a difference if you have a family history of heart attack and stroke? Many people I’ve met over the years don’t think so, citing examples of people they know who don’t watch what they eat and yet have lived a long time, along with examples of other folks who ate healthfully yet died young from heart problems. Meanwhile we hear from health professionals that what you put into your stomach is absolutely a key to your health. So it’s a fair question: Is the diet mightier than the gene, or isn’t it?

On this point, I admit that over the years, my opinion has wavered from time to time… but now I’m siding squarely with the health pros. Here’s why: A recent study of adult twins found that those who followed a Mediterranean diet had better heart health than those who did not.

Reverse Genetic Risk

Genes are only part of our health story, explains Jeffrey S. Bland, PhD, FACN, FACB, author of the new book, Genetic Nutritioneering: How You Can Modify Inherited Traits and Live a Longer, Healthier Life. The propensity for certain health conditions that you inherit from your family is not, by a long shot, the sole determinant of whether or not most folks will get sick. Your lifestyle choices have a significant impact, especially when it comes to chronic illnesses such as heart disease.

The Mediterranean diet, rich in vegetables, fruits, grains and omega-3 fatty acids, is well known for its protective effects against cardiovascular disease. Researchers at Indiana University set out to ask a different question: Are these cardiovascular benefits independent of genes?

To determine the answer, they compared the food diaries of 276 middle-aged male twins (some fraternal and some identical) with the results of their electrocardiograms (ECGs), records of electrical activity of the heart. In particular, they looked at heart rate variability (HRV), the differences in time between heartbeats during daily activities. A higher variability is a sign of better heart function. (For information on heart-rate variability and what it means to your health, see Daily Health News, “Does Your Heart Rate Vary?”, August 10, 2009.)

The researchers scored the twins’ food questionnaires according to how closely they matched the Mediterranean diet, with close adherence reflected by a high score. They found that higher scores were associated with higher HRVs — even in the group of identical twins with shared genes and certain shared environmental factors. The authors concluded that “whether or not a person has an adverse genetic background or other risk factors for cardiovascular disease, this person would be likely to have better cardiac autonomic function if he/she follows a diet similar to the Mediterranean diet.” In other words, the old excuse for eating that big slice of New York cheesecake — “Why worry? It’s all in the genes!” — just doesn’t stand up.

Living Healthfully Matters More

Researchers have identified many genes implicated in illnesses such as heart disease, cancer and diabetes, and recent studies demonstrate that our genes are not necessarily our destiny. Just because heart disease or cancer “runs in your family” does not mean that you will fall prey to it. In fact, Dr. Bland told me that “positive environmental stimuli” — which he defines as a healthful diet… a lifestyle that includes plenty of exercise… sufficient management of stress… and reasonable avoidance of disease-causing microbes and pollutants — can effectively “turn off” genes that cause disease and “turn on” those that promote wellness.

More research is needed to explore the precise relationship between heart disease and underlying genetic susceptibilities. In the meantime, to positively modify your own “gene expression” against heart disease, Dr. Bland recommends…

  • Make your menu Mediterranean. Adopt healthful, tasty elements of the Mediterranean diet, such as more fresh fruits and vegetables (at least nine servings daily), nuts and legumes, whole grains, two or three servings of fish a week and moderate consumption of monounsaturated fatty acids (e.g., olives and olive oil).

Dr. Bland’s advice: Eat plenty of cruciferous vegetables such as kale, broccoli, cabbage, Brussels sprouts and cauliflower. These are rich in heart-healthy fiber and nutrients such as potassium, magnesium, folic acid and vitamin C.

  • Junk the junk food. Reduce your intake of processed products, items made with refined flour and sugar and inflammatory fats (trans and saturated), such as pizza, and other fast food, white bread, doughnuts, candy and soft drinks.

Dr. Bland’s advice: To reduce sugar intake and flush toxins out of your body, replace all beverages with water.

  • Balance your life. Strive for an optimal balance of rest and exercise. Whenever possible, make time for daily aerobic activity (e.g., fast walking or biking) and stress management (meditation, yoga, deep breathing, etc.) — ideally 20 to 30 minutes for each.

Dr. Bland’s advice: Get adequate sleep at night — on average seven to eight hours — to help reduce stress, maintain a healthy weight and improve health potential.

  • Take your health seriously. It is possible that you may have underlying infections even if they aren’t making you ill in obvious ways. Chronic or hidden infections with microorganisms such as viruses, bacteria, yeasts or parasites often lay at the root of heart disease.

Dr. Bland suggests: See your doctor if you aren’t feeling right to determine whether you need blood tests to identify unknown issues. A healthy lifestyle with adequate nutrition, regular exercise and effective stress management will strengthen the immune system and help to suppress infections.

It’s true that your genetic profile was determined long before you were born, but Dr. Bland urges everyone to be aware that decisions you make every day of your life to control environmental and dietary choices are very important — perhaps more important — in protecting you from disease. Each day you commit to treating your body well, you reduce your risk for illness and improve your health potential.

Jeffrey S. Bland, PhD, FACN, FACB, nutritional biochemist and registered clinical laboratory director, founder, Institute for Functional Medicine, chief science officer, Metagenics, Inc. (, a provider of medical foods and lifestyle medicine programs, based in Gig Harbor, Washington. He is author of Genetic Nutritioneering: How You Can Modify Inherited Traits and Live a Longer, Healthier Life and The 20-Day Rejuvenation Diet Program (both from McGraw-Hill).