UCLA scientists have found that genes in the brain can be damaged by fructose in a way that could lead to diseases including diabetes, cardiovascular disease and Alzheimer's disease. From cereal to salad dressing, Americans get most of their fructose in foods that are sweetened with high-fructose corn syrup, an inexpensive liquid sweetener made from cornstarch. However, researchers have discovered that the benefits of an omega-3 fatty acid known as docosahexaenoic acid, DHA, may be able to reverse the harmful changes produced by fructose. DHA strengthens synapses in the brain and enhances learning and memory.
"DHA changes not just one or two genes; it seems to push the entire gene pattern back to normal, which is remarkable," Xia Yang, a senior author of the study and a UCLA assistant professor of integrative biology and physiology, said in a UCLA press release. "And we can see why it has such a powerful effect."
While the human body naturally makes small amounts of DHA, it does not make enough. Therefore, it is essential that people get DHA from food. Seafood, like salmon, is the premier dietary source of omega-3 fatty acids. Both farmed and wild salmon are great sources of DHA as well as eicosapentaenoic acid (EPA), another beneficial omega-3 fatty acid. Due to the higher fat content, farm-raised salmon has as much or more EPA and DHA per serving than wild-caught, according to the 2015 Dietary Guidelines Advisory Committee. In fact, Norwegian farm-raised salmon contains 1300 mg DHA per 100g fish.1 While both farmed and wild salmon are terrific sources of DHA and EPA, Norwegian farm-raised salmon can be the better option, as it is reasonably priced and available year-round.
The benefits of seafood consumption were reinforced with this year's release of the 2015 USDA Dietary Guidelines. While Americans are known to eat too much protein, nearly all eat far too little seafood—the average American eats one serving of fish per week, while the average pregnant woman eats half a serving per week. As part of the 2015 USDA Dietary Guidelines, Americans are now encouraged to eat seafood at least twice weekly because of its heart and weight benefits. DHA and EPA are abundant in oily fish such as salmon, tuna, mackerel and herring. Consuming 250 milligrams daily of DHA and EPA—the amount in a 3-ounce farmed salmon fillet—has been associated with reduced heart disease risk.
The benefits of omega-3 fatty acids have been supported for years, but this new study shows just how important DHA could be in preventing some of America's most prevalent diseases. While the latest research is significant, more research will be needed to determine the extent of its ability to reverse damage to human genes.
1 National Institute of Nutrition and Seafood Research (Norway), 2010