LAS VEGAS—Recommending an amount and type of daily polyunsaturated fatty acid (PUFA) consumption may help some races achieve better health; however, it could harm other populations, according to Floyd H. "Ski" Chilton, III, Ph.D., professor in the department of physiology and pharmacology and director at the National Institutes of Health (NIH) Center for Botanical Lipids at Wake Forest University Baptist Medical Center.
At SupplySide West, Chilton said his research could show that some populations would benefit from taking certain types of PUFAs over others. For instance, his research suggests flaxseeds may be more efficacious in African Americans than in Caucasians due to a genetic variation on a certain chromosome. This budding research could make a tremendous effect for therapeutic food and supplement manufacturers who can better help consumers by creating population-specific goods.
Humans evolved to depend on PUFAs to store energy, and to build optimal brain and immune health; however, the current Western diet, which is increasingly becoming the world’s standard diet, has put a strain on humans’ health. “These dietary changes have been catastrophic," Chilton said.
Chilton noted a study published in the American Journal of Clinical Nutrition in 2005 that reported 72 percent of calories from the foods we eat today were not eaten by our ancestors. In fact, he noted, it’s in the last 70 years that the food supply has made its biggest changes. We have malnutrition in a time of abundance, he said, pointing out that eight of the top ten causes of preventable deaths in the United States are diet related.
In recent decades, the amount of PUFA consumption has increased dramatically, he said, but most of these are from long-chain omega-6 fatty acids, which are associated with an increased risk of heart disease.
Chilton discussed studies completed at his lab. These studies examined genetic variations on chromosome 11 associated with PUFA metabolism, and found African Americans had much higher blood levels of inflammatory omega-6 PUFAs than did those of European descent, and African Americans were more likely to carry the efficient converter genes compared with Americans of European ancestry sampled from the same geographic regions. Additionally, the results were supported by examining catalogs of genetic information taken from different world populations. Taken together, these studies suggest people of African descent may be more likely to have a genetic variant that allows them to make brain-building omega-3 fatty acids from plants such as flaxseeds; but this same genetic variant also likely renders its carriers more vulnerable to ill effects from the much more abundant omega-6 PUFAs.
By looking at chromosome 11, Chilton said his research shows African Americans have more arachidonic acid (AA); where Caucasians have more dihomo-gamma-linolenic acid (DGLA), even though they eat the same make up PUFAs in the diet. DGLA is less inflammatory than AA, and this genetic difference may explain why African Americans are more likely to suffer from heart disease than Caucasians.
His lab is now examining metabolism and efficacy of different PUFA based dietary supplements in individuals with specific common genetic variants.
