Omega-3s: What They Are
“Omega-3s are named for the placement of the last double bond in the molecule, which is three positions from the omega tail,” explains Melissa Majumdar, RD, a spokesperson for the Academy of Nutrition and Dietetics and the nutrition coordinator for the Brigham and Women’s Center for Metabolic and Bariatric Surgery in Boston. ALA is the precursor to EPA and DHA, which means your body can convert very small amounts of ALA into the other two fatty acids, notes Sonya Angelone, RDN, a spokesperson for the Academy of Nutrition and Dietetics in San Francisco. “If you’re pregnant, you’ll need more omega-3 fats because they play an important role in the growth and development of the fetal brain and neural tubes,” points out Armul. But pregnant women may be wary of these guidelines because of the risk of mercury that’s present in some fish. In this case, expectant women should still aim for at least 8 oz a week (but less than 12 oz) to aid in cognitive and vision development for their babies, Majumdar explains. And be sure to choose fish lower in mercury, such as wild salmon, herring, sardines, trout, and Atlantic or Pacific mackerel (but not king mackerel, which is high in methyl mercury).
The Safety of Omega-3 Supplements
Most people get more than enough omega-6s in their diet; the benefit comes from a healthy ratio of omega-3s to omega-6s, and this can be improved by eating more omega-3s without a change in consumption of omega-6s. As for omega-9s, your body can actually make this substance, but adding it to your diet is definitely beneficial. “Omega-9s are widely believed to increase levels of HDL, which is the ‘good’ cholesterol, and lower the ‘bad’ one (LDL),” explains King. You can find omega-9s in olive oil, olives, avocados, nuts, and seeds. Evidence related to cancer prevention isn’t clear, as it varies by cancer type, genetic factors, and gender, says Majumdar.