Do You Need an Omega-3 Supplement If You Don't Eat Fish?

There is confusion about dietary fat, and especially whether or not we need to work to get the essential fatty acids omega 6 and omega 3, into our diet. These are called "essential" fats because they are not made by the body, yet they work hand in hand to lower inflammation, fight heart disease, and inhibit the dangerous clots from forming in the bloodstream. Most of us get plenty of omega-6 in the vegetable oils we use to cook with, but omega-3s are harder to come by, but no less important.

Rather than avoid healthy fats from plant-based foods, your body needs polyunsaturated fats to thrive and survive, to help your cells create strong membranes and brain cells to connect and function at warp speed. And while our bodies can make most of what we need, we can’t make the all-important omega-3 fatty acids, so instead, we need to get these from our diet. The best sources of omega-3s are either oily fish such as sardines, salmon, and mackerel, or fish oil. But if you're avoiding fish and oil, omega 3s can be found in nuts such as walnuts and seeds such as flaxseeds and chia seeds, but the question is, are you getting enough?

Omega-3 fatty acids are essential to your health, including your brain and heart

A diet high in omega-3 fatty acids has been linked to improved cardiovascular health, as well as improved brain function, according to a large review study from July 2021 that found that among nearly 150,000 participants in dozens of studies, daily doses of omega-3 helped lower cardiovascular mortality risk. But if you are trying to eat plant-based, omega-3 is harder to get, since if you're not eating fish, you may not be getting enough just by eating nuts and seeds. In that case, should you take a supplement? Here's what experts say about omega-3 fatty acids and how to get enough on a plant-based diet.

What Are Omega-3 Fatty Acids?

There are three main types of dietary omega-3s: Alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). While ALA is a short-chain omega-3 fatty acid, the other two are long-chain omega-3 fatty acids.

You can only get ALA through your diet, by eating chia seeds, hemp seeds, flaxseed or linseed, as well as rapeseed oil, and walnuts. Your body then converts ALA into EPA and DPA, which have the most health benefits. “EPA is thought to play a role in heart health while DHA is a major component of the grey matter of the brain and is found in the retina and cell membranes,” says Andrea Rymer, R.D. with the Vegan Society in the UK.

Because DHA plays an important role in brain and eye health, especially during growth and development stages, it’s particularly important to get enough during pregnancy, breastfeeding, and childhood. In fact, compelling research from Cochrane shows that omega-3 intake during pregnancy helps reduce the risk for early preterm birth and low birthweight babies, says Elana Natker, R.D., director of consumer and health professional communication for the Global Organization for EPA and DHA Omega-3s.

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Can You Get Enough Omega-3s Through Diet Alone?

This is a tricky question, as it also depends on how well your body can convert ALA into DHA and EPA. “Conversion rate is variable and tends to be based on genetics,” Natker says. Conversion is further complicated by the fact that your body requires enzymes to make this conversion. Yet it has to compete against other processes in the body to get them, namely the conversion of omega 6 fatty acids, which are typically found in oils like sunflower and corn often used in processed foods.

Research into whether our bodies can get adequate EPA and DHA through natural conversion rates from our food is lacking. Most of the research has been done on supplementation, or on the meat- and fish-eating population, Rymer says, but one study from the American Journal of Clinical Nutrition should give vegans assurance that plants provide what they need.

The study concluded that women on plant-based diets have significantly more omega-3 fatty acids in their blood than ovo-lacto vegetarians and fish and meat-eaters. “Despite zero intake of long-chain omega-3s eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and a substantially lower intake of their plant-derived precursor alpha-linolenic acid (ALA), vegan participants converted robust amounts of shorter-chain fatty acids into these long-chain fatty acids,” according to a statement by the Physicians Committee for Responsible Medicine.

That’s why the Vegan Society hasn’t issued a blanket recommendation for all vegans to take a separate supplement. “(EPA and DHA) supplements do not appear to be essential for vegan health because our bodies can make these fatty acids from ALA,” Rymer says. About two grams of ALA per day has been associated with a modest lowering of heart disease risk, which you can get by eating six walnut halves, two tablespoons of hemp seeds, or a tablespoon of chia seeds or ground linseed every day.

There are exceptions, though, and if you’re unable to meet your ALA needs through diet, Rymer recommends taking a microalgae long-chain omega-3 fat (EPA and DHA) supplement. You might also consider supplementing if you’re pregnant, breastfeeding, or going through childhood.

Natker, however, believes supplementing is best. “It’s better to rely on a vegan EPA and DHA omega-3 supplement versus plant-based ALA-containing sources to give you the EPA and DHA you need,” she says. If you are going to supplement, Natker recommends, per recent research, that adults take 1000 milligrams (mg) of combined EPA and DHA omega-3s per day. Most vegan omega-3 supplements are derived from marine microalgae, but check labels to make sure you’re choosing a vegan one.

Regardless of your supplement decision, avoid consuming lots of short-chain omega-6 fatty acids called linoleic acid, as this can reduce the amount of long-chain omega-3 fats your body makes from the ALA you’re eating, Rymer says. Some tips from the Vegan Society to combat this: If you’re consuming oil, choose vegetable oils instead of sunflower, corn, and sesame oils, all of which contain high amounts of LA, and limit the amount of pumpkin and sunflower seeds you eat to about one-quarter cup per serving.

Bottom line: Plant-based eaters are able to get enough omega-3 fatty acids through plant-based sources such as walnuts, seeds, seaweed, and algae. If you are unable to get enough omega-3 fatty acids through diet alone, consider adding a supplement to your routine to fill in the gaps. Always consult your doctor before you begin to take a new supplement.