If you’re familiar with heart-healthy omega-3 fatty acids, you may already know that oily fish like mackerel, salmon, or sardines are some of the most efficient omega-3 sources.
But while the American Heart Association recommends eating two servings of fish per week, vegetarians and vegans can still stock up on this essential nutrient. Read on to see how plant-based omega-3s compare to fish oil, and how algae can up your omega-3 game.
Understanding the different kinds of fat
When it comes to dietary fat, there’s the good, the good-in-moderation, the bad, and the essential.
Unsaturated fats (both polyunsaturated and monounsaturated) are good—they can lower bad cholesterol and rates of cardiovascular problems. Saturated fats, meanwhile, are good in moderation, while trans fats are just bad—most nutrition experts recommend avoiding them altogether.
Which brings us to the essential fats.
Omega-3s are both a good (polyunsaturated) and essential fatty acid. Essential means that the body needs it but can’t make it, so it has to be obtained through diet or supplements.
Your body needs omega-3s for brain function and cell growth, and they also have wide-ranging functions in your heart, blood vessels, lungs, immune system, and endocrine system.
Are all omega-3s created equal?
Well, (surprisingly) no.
There are three types of omega-3 fatty acids that affect the human body: ALA, EPA, and DHA.
ALA (alpha-linolenic acid) comes from plant oils, while EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) come from fish oils.
Generally speaking, EPA promotes heart health, DHA promotes brain health (DHA makes up 40% of the fatty acids in the brain), and plant-based ALA helps promote overall health.
If you want to get into specifics of the many and diverse roles that omega-3s play in your health, there’s been extensive research on the topic over the past 20-odd years. Just keep in mind that most studies have focused on fish-derived EPA and DHA—not ALA.
How to get your omega-3 daily serving
Despite all the internet love for EPA and DHA-rich fish oil, the National Institutes of Health has only formally established a recommended amount for plant-based ALA (men should aim for 1.6 grams daily while women should get 1.1 grams).
You’ll typically meet your ALA needs through diet since there are many good sources of ALA omega-3s. Just one tablespoon of flaxseed, for example, will contain 2.3 g.
Good sources of ALA omega-3s include nuts and seeds, beans, and even certain cooking oils. Some foods, such as certain eggs and yogurt, are specially fortified with omega-3s. Foods containing high levels of ALA from the USDA include:
cold pressed flaxseed oil 7.258 g per 1.0 tbsp
dried chia seeds 5.055 g per 1.0 oz
dried walnuts 3.346 g per 1.0 cup, chopped
hemp seeds 2.605 g per 3.0 tbsp
canola oil 1.279 g per 1.0 tbsp
navy beans 1.119 g per 1.0 cup
pesto 1.066 g per 0.25 cup
soybean oil 0.923 g per 1.0 tbsp
edamame, frozen 0.555 g per 1.0 cup
refried beans, vegetarian 0.426 g per 1.0 cup
In comparison, most health organizations recommend about 250 mg of DHA and EPA per day, the equivalent of 8oz of seafood each week.
But while EPA and DHA are found in oily fish, fish don’t produce omega-3s. Instead, EPA and DHA are actually synthesized by the microalgae that these fish ingest (more on that later).
The health benefits of EPA and DHA omega-3s
The National Institutes of Health now cautions that while omega-3s can reduce levels of triglycerides (which are markers for heart disease and stroke risk), current research indicates omega-3s do not reduce risk of heart disease
But while enthusiasm for fish oil for heart health seems to be dimming, EPA and DHA supplements still offer benefits. Other research has found a promising relationship between EPA and DHA omega-3s and depression, anxiety and inflammation, and even asthma in children.
Does ALA convert into EPA and DHA omega-3s?
So can vegetarians and vegans get by on ALA alone? Maybe.
The body can actually convert plant-sourced ALA into EPA and DHA, and there’s some evidence that people who don’t eat fish convert more of their ALA than people who do. In other words, vegans and vegetarians may be able to get by with only ALA omega-3s.
That said, scientists aren’t sure if the amount of ALA that converts to EPA (as little as 5%) and DHA (as little as .5%) is enough to ensure optimal health, or just prevent a deficiency.
In other words, your body will create a very small amount of EPA and DHA for use even if you avoid eating its best dietary sources, which are oily fish. However, if you’re vegan and vegetarian and want to reap the additional health benefits of EPA and DHA, you’ll need to use a supplement.
And for now, research shows that DHA and EPA supplements aren’t a bad idea. One study notes that while vegetarians already have reduced cardiovascular risk markers compared to omnivores, increasing omega-3 concentrations might yield further risk reduction, though there’s not yet enough research to support this hypothesis.
Another study recommends supplementation for those with increased needs, including pregnant and lactating women, older people, and those with chronic disease.
Vegetarian EPA and DHA from algae
There are a variety of supplements available that are derived from algae. Like fish oil, you can find algae (or “algal”) oil in either softgels or liquid and at similar prices.
Look for supplements that identify themselves as vegan/vegetarian and state their EPA and DHA content.
Even if you’re not vegetarian, you may choose algae over fish oil. One advantage is that unlike fish oil, algae oil is cholesterol free. Additionally, algae also lacks potential contaminants like mercury that can be found in fish, is more sustainable produced and environmentally friendly, and lacks that signature fishy odor.
Given that very little ALA converts into EPA and DHA, for now algae oil is likely the best way for a vegan or vegetarian to supplement their diet with these nutrients.
The bottom line
Omega-3 fatty acids are essential in promoting overall health. Of the three types, only ALA is officially recommended by the NIH, and most people can get enough ALA through diet.
EPA and DHA are commonly found in fish, but actually originate in algae. They serve functions in the brain and heart, and they may offer additional benefits for a range of symptoms for mild depression, ADD, alzheimer’s, and systemic inflammation.
Many obtain EPA and DHA through eating fish or by taking a fish oil supplement. Vegetarians or anyone seeking a plant-based alternative can get these nutrients from algal oil, which is derived from the original source of EPA and DHA: algae.