Nutritional Pearls: Diet Affects Cellular Aging in the Longer Term

Joe is a 65-year-old man who is concerned about staying healthy as he gets older. He tells you that while he tries to eat as healthy as possible, he normally follows a Western-style diet high in red meat, sugar, and refined grains.

How would you advise your patient?
(Answer and discussion on next page)

Dr. Gourmet is the definitive health and nutrition web resource for both physicians and patients with evidence-based resources including special diets for coumadin users, patients with GERD/acid reflux, celiac disease, type 2 diabetes, low sodium diets (1500 mg/d), and lactose intolerance.

Timothy S. Harlan, MD, is a board-certified internist and professional chef who translates the Mediterranean diet for the American kitchen with familiar, healthy recipes. He is an assistant dean for clinical services, executive director of The Goldring Center for Culinary Medicine, associate professor of medicine at Tulane University in New Orleans, faculty chair of the all-new Certified Culinary Medicine Specialist program, and co-chair of the Cardiometabolic Risk Summit.

Now, for the first time, Dr. Gourmet is sharing nutritional pearls of wisdom with the Consultant360 audience. Sign up today to receive an update from the literature each week.

Answer: Mediterranean-style diet is one that you can live with long term and will likely keep your telomeres longer.

Telomeres are repeating DNA sequences that form a protective cap on certain chromosomes. Each time the chromosome divides to create new cells, the telomeres get shorter and shorter until the chromosome breaks down and the cell dies. This is known as "programmed cell death," a normal process that can, however, be set off prematurely. That premature cell death has been linked to inflammatory states such as cancer, heart disease, and high blood pressure. In 2011, I wrote about a study that linked longer telomere length to higher intake of omega-3 fatty acids from fish and shellfish, and in 2014, I wrote about another study that linked longer telomeres to a higher Mediterranean Diet score.^1,2

The Research

Both those studies were done on largely white populations in the United States: the first in over 600 men and the second in the Nurses' Health Study, which focuses on women. Today's research, however, comes from South Korea, where nearly 2,000 Korean men and women participated in a long term study that started in 2001, when the participants were between 40 and 69 years of age.³

At the start of the study the researchers administered a food frequency questionnaire specifically created and tested to be accurate for Koreans. At that time they also gathered demographic data and health information, including blood tests, height, and weight. Ten years later the participants' blood was drawn and their telomeres were measured.

Using the responses to the food frequency questionnaire, the authors were able to identify 2 broad dietary patterns. They called one a "prudent dietary pattern," which was characterized by a higher intake of whole grains, legumes, seafood, vegetables, and seaweed. The second they called a "Western dietary pattern," which as you might guess included higher intake of refined grains, red or processed meats, and sweetened carbonated beverages.

The Results

It shouldn't surprise you that even after taking into account such variables as body mass Index, smoking status, the amount of physical activity, and whether the participant had high blood pressure, diabetes, or poor cholesterol scores, those who followed the prudent dietary pattern tended to have longer telomeres than those following a Western dietary pattern. What's particularly interesting, however, is what the authors found when they looked at specific food types.

Once again, it will be no surprise that higher intake of legumes, nuts, and fruit were linked to longer telomeres, but so was seaweed, dairy products, and coffee! Even more interesting is that the effects of seaweed and fruit were greater for men, while the effect of coffee was greater for women. On the other hand, greater intake of red or processed meat and sweetened carbonated beverages were most strongly linked to shorter telomeres, with the effects of red or processed meats being slightly stronger for men than women.

What’s The “Take Home”?

These types of studies assume that people tend to have the same dietary pattern for the long term—and this has indeed been shown in corroborating research. That said, people can and do change their diets. The authors acknowledge that this is a possibility and note that their research still shows that one's diet, even 10 or more years previously, appears to still have an effect on telomere length. Your take-home should be that a Mediterranean-style diet (which their "prudent dietary pattern" strongly resembles) is one that you can live with long term and will likely keep your telomeres longer, too.

References:

1. Bou M, Fung TT, Prescott J, et al. Mediterranean diet and telomere length in Nurses’ Health Study: population based cohort study. BMJ. 2014;349:6674
2. Far RF, Lin J, Epel ES, et al. Association of marine omega-3 fatty acid levels with telomeric aging in patients with coronary heart disease. JAMA. 2010;303(3):250-257.
3. Lee JY, Jun NR, Yoon D, et al. Association between dietary patterns in the remote past and telomere length. Eur J Clin Nutr 2015;69:1048-1052.