Vegetarians and vegans, like everyone else, need a source of omega-3 in their diets. Omega-3s are essential to good health.
Foods that contain appreciable amounts of alpha-linolenic acid (ALA), the vegetarian omega-3:
*highest sources
Vegetarians and vegans are not more likely to be deficient in omega-3s compared to meat-eaters. It is fairly easy for everyone consuming a balanced diet to meet the Institute of Medicine (IOM) recommendations for alpha-linolenic acid intake; equivalent to 0.6% - 1.2% of daily energy.
A typical adult consuming 2000 calories per day would need about 1.3 – 2.7 grams ALA per day; equalling about one-quarter of a teaspoon of flax seed oil, less than a tablespoon of walnuts or 1.3 tablespoons of soybean oil. But don’t worry about numbers – a balanced diet is very unlikely to be deficient.
Everybody should strive to balance their intake of omega-6 fats to omega-3 fats; most people (including vegetarians and vegans) eat too many omega-6s that are found in nuts, seeds and grains. It is important to balance these with sources of concentrated omega-3.
Foods
Flax seed is the richest source of ALA, but the fats are stored within the seed. For the body to use this hidden fat, choose ground (milled) flax seed or flax oil instead of whole flax seeds.
Hemp seed and hemp seed oil contain appreciable amounts of omega-3 but more omega-6 than flax (remember, the goal is to increase omega-3 in relation to omega-6).
Supplements
Flax oil, perilla oil and hemp oil can be taken as supplements in liquid or capsule form. Most capsules are made from gelatin though, which is made from animal bones. Remember that it takes 16 capsules to make one tablespoon of liquid oil.
These liquid oils cannot be heated but can be added to smoothies, used in salad dressings or taken straight off the spoon. Some people find the nutty taste of flax or hemp oil enjoyable.
Vegetarian omega-3s are converted to the longer-chain fats EPA and DHA inside the body. The conversion rate is consistently low in most people, yet EPA and DHA are the end products that are associated with health benefits like cardiovascular protection and brain health. For this reason, some people choose to take a high-DHA algae supplement.
Megadosing
Clinical trials have shown benefits to heart and cardiovascular health in subjects taking more than one gram per day of EPA and DHA from fish oil. While these effects are well-established, it does not mean vegetarians need to megadose as well. Vegetarians and vegans have lower rates of cardiovascular and chronic disease than the general population to start with. Remember, not eating fish does not mean omega-3 deficiency. Supplements for adults and children can be discussed with a health care practitioner.
Fortified (“Enriched”) Foods
Because of their nutritional importance and potential health benefits (especially in children), many foods are now being fortified with omega-3s. Fortification may list “omega-3”, “EPA”, “DHA” or “ALA/alpha-linolenic acid”. EPA and DHA come from fish unless the source is specifically listed as algae. Products may differ by country or by region; food labels are the best source of current information.
Foods fortified with vegetarian omega-3 sources:
Fortified foods that use non-vegetarian (usually fish) sources of DHA or omega-3s:
Resources:
Health Canada: Frequently Asked Questions. What should vegetarians (or those who do not eat fish) do about the recommendation to eat at least two Food Guide Servings of fish each week?
Institute of Medicine. Dietary Reference Intakes (DRIs): Recommended Intakes for Individuals.