Over the past couple of years, omega-3 fatty acids have received profound media attention due to their wide range of health benefits. Although they serve as a powerful source of nutrition, excess omega-3 fatty acids can come with a cost to overall health.
Omega-3 fatty acids are polyunsaturated fatty acids, which we must obtain from our diet through foods such as fish oil or some plants and nut oils. The more potent and important omega-3 fatty acids
are docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). EPA is only present structurally in minute quantities and is constantly in need of replenishment. DHA, the main building block for brain and retinal development, is more abundant in the body and aids in the formation of neural transmitters.
According to Amy Jamieson, MS, PES, AASDN, a nutrition lecturer and faculty of the Department of Exercise and Sport Studies at UCSB, DHA has many other benefits for our bodies also.
“Health benefits include an increase in HDL — the good cholesterol — and a decrease in LDL — the bad cholesterol — which results in improved blood cholesterol levels and reduced risk of heart disease,” Jamieson said.
However, David Valentine, a professor of Earth Science and Biology at UCSB, and Raymond Valentine, professor emeritus of Plant Sciences at UC Davis, have discovered that taking omega-3 fatty acids may come with a price. David Valentine focuses largely on the role of omega-3s in cellular membranes, ranging from within human neurons to plants and bacteria, while Raymond Valentine researches how to engineer genes from ocean plants to harvest crop plants for a more accessible source of omega-3. They published a book outlining their findings titled, Omega-3 Fatty Acids and the DHA Principle.
According to their journal article in Progress in Lipid Research, “omega-3 fatty acids in cellular membranes: a unified concept,” DHA and EPA comprise a large portion of the cellular membrane of bacteria and human cells. DHA and EPA are oxidatively unstable in nature and can be easily broken down into harmful byproducts. In bacteria, oxidation is less likely because most bacteria live in an anaerobic environment. But in humans, this is the opposite. The combination of unsaturated omega-3 fatty acids and oxygen present in our brains causes inevitable oxidation, which could lead to brain aging and disease.
Jamieson said that these causes and effects of DHA oxidation could pose a risk when deciding whether or not to take a fish oil supplement.
“Supplements are always controversial — studies show that fish oil supplements can improve cholesterol health and help in reducing risk of heart disease, but high doses can be harmful. Natural sources — food sources — are always a better choice,” Jamieson said.
It is not advised to completely denounce omega-3 fatty acids, however, excess dosage could cause adverse effects. These fats are very important in increasing our neural development; despite the downside of their oxidation, they have a myriad of health benefits which outweigh the disadvantages.