Can You Have an Omega-3 Deficiency and What Are the Effects?

Becoming deficient in omega-3 fatty acids is relatively rare, but if you’re vegan or don’t eat seafood every week, then you may not be getting enough, notes Angelone. Deficiencies can occur, though, with some people reporting fatigue, inflammation, and depression, says King. One classic sign is rough, red, scaly skin with itching. But since there’s no reasonable way to measure the omegas in your body, try to eat more foods that are rich in these fatty acids or consider a supplement, she adds.

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).

Can’t stomach anything with gills? A supplement may be the solution, particularly if you’re at risk for cardiovascular disease or you’re planning to have a baby, counsels Majumdar. Getting omega-3s from whole foods is always the best choice, but for those who simply cannot meet the recommended intake of fish each week, a supplement can be a good alternative.

“Most fish oil or omega-3 supplements contain EPA and DHA, which are from animal sources and tend to be more bioavailable [than the ALA from plant sources],” says King. Always speak with your doctor before taking a supplement, as it may not be appropriate in every case. Fish-free microalgae supplements that contain both EPA and DHA are also an option.

The Safety of Omega-3 Supplements

Two other fatty acids, omega-6 and omega-9, are also part of a healthy diet. “Omega-6s are important building blocks for cell membranes and can only be obtained from food or a supplement,” notes King. Good sources of omega-6 include flaxseed meal and oil, pumpkin seeds, pine nuts, pistachios, and acai. Omega-6 is also present in many popular, processed foods that contain corn oil, though those tend to be less than healthy.

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.

Although the majority of omega-3 research tends to be in the cardiovascular field, there are other areas in which fatty acid research has shown promising effects, including inflammation, colon cancer, and insulin resistance, reports King. “And it may help with ADHD symptoms, the reduction of depression and anxiety, eye health, and Alzheimer’s,” she adds.

Evidence related to cancer prevention isn’t clear, as it varies by cancer type, genetic factors, and gender, says Majumdar.