ALA is not as active in the body and must be converted to two other forms of omega-3 fatty acids — eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) — to bestow the same health benefits (4).
Unfortunately, your body’s ability to convert ALA is limited. Only about 5% of ALA is converted to EPA, while less than 0.5% is converted to DHA (5).
Additionally, keep in mind your omega-6 to omega-3 ratio, as a diet low in omega-3s but high in omega-6s can increase inflammation and your risk of disease (6).
One study found that consuming a diet with chia seeds, nopal, soy protein and oats decreased blood triglycerides, glucose intolerance and inflammatory markers (7).
A 2007 animal study also found that eating chia seeds decreased blood triglycerides and increased both “good” HDL cholesterol and omega-3 levels in the blood (8).
In fact, one study found that an increased intake of cruciferous vegetables is associated with a 16% lower risk of heart disease (11).
Algal oil, a type of oil derived from algae, stands out as one of the few vegan sources of both EPA and DHA (14).
One study compared algal oil capsules to cooked salmon and found that both were well tolerated and equivalent in terms of absorption (15).
In fact, a recent animal study found that supplementing mice with a DHA algal oil compound led to an improvement in memory (16).
Most commonly available in softgel form, algal oil supplements typically provide 400–500 mg of combined DHA and EPA. Generally, it is recommended to get 300–900 mg of combined DHA and EPA per day (17).
They may do this by preventing the formation of blood clots and helping the heart recover after a heart attack (20, 21).
Walnuts are loaded with healthy fats and ALA omega-3 fatty acids. In fact, walnuts are comprised of about 65% fat by weight (23).
A 2011 animal study found that eating walnuts was associated with improvements in learning and memory (24).
Another animal study showed walnuts caused significant improvements in memory, learning, motor development and anxiety in mice with Alzheimer’s disease (25).
Both flaxseeds and flaxseed oil have been shown to reduce cholesterol in multiple studies (27, 28, 29).
Another study found that flaxseeds could help significantly lower blood pressure, particularly in those with high blood pressure (30).
One study in 20 elderly participants replaced soybean oil with perilla oil and found that it caused ALA levels in the blood to double. In the long term, it also led to an increase in EPA and DHA blood levels (32).
Perilla oil is very rich in omega-3 fatty acids, with ALA making up an estimated 64% of this seed oil (33).
To maximize its health benefits, perilla oil should be used as a flavor enhancer or dressing, rather than a cooking oil. This is because oils high in polyunsaturated fats can oxidize with heat, forming harmful free radicals that contribute to disease (34).