Want to make sure you are getting enough omega-3 fatty acids on a plant-based diet? Omega-3s for vegetarians and vegans are harder to come by, but there are some dietary factors that we can control to help improve our access and the availability of this important nutrient.
Long dispelled are the myths of inadequate protein intake in vegetarian diets. We now know that a balanced and varied vegetarian diet, containing nuts, seeds, organic tofu, eggs, legumes, and quinoa will provide us with all our body needs. One uncertainty that continues to linger is whether or not a vegetarian diet can provide sufficient omega-3 fatty acids. I’ve outlined the recommended intake of plant-based omega-3s for vegetarians and vegans, and have included tips on how to maximize the availability of this important nutrient by the body.
What’s All the Fuss About Fish?
Seafood and Omega-3 Fatty Acids
Omega-3 fatty acids in the form of EPA and DHA (eicosapentaenoic acid and docosahexaenoic acid) are mainly found in seafood, with lesser amounts in seaweed and other algae. It is the EPA and DHA omega-3 fatty acids that have been linked to numerous health benefits.
What Are the Health Benefits of EPA and DHA?
It is these compounds that have been well researched for their important role in reducing inflammation, blood clots, and blood pressure. They are also a major component of our retina, brain, cell membranes and sperm. Studies have linked DHA deficiencies to several neurological and behavioural disorders such as depression, schizophrenia, Alzheimer’s disease and Attention Deficit Hyperactivity Disorder (ADHD).
Omega-3s for Vegetarians and Vegans
Sources of Omega-3 Vegetarian and Vegan Foods
Plant-based sources of omega-3 fatty acids include chia seeds, flaxseeds, soybeans, hemp hearts and walnuts. Flaxseeds contain the most amount of omega-3 fatty acids in the plant-based world. See my post Chia vs Flax vs Hemp – Which One Is Healthier And More Sustainable?
Are Omega-3s from Vegetarian and Vegan Foods Healthy?
Vegetarian and vegan omega-3 foods contain the less potent omega-3 called alpha-linolenic acid (ALA), unlike the powerful DHA and EPA found in seafood. ALA can be converted into DHA and EPA but unfortunately, the conversion isn’t always very efficient. It is estimated that as little as 2% to 10% of ALA converts to DHA and EPA.
What Blocks The Conversion of Omega-3 from Vegetarian and Vegan Foods to EPA and DHA?
A number of factors can block the conversion of ALA from vegetarian and vegan omega-3 rich foods into DHA and EPA. A big one includes excess omega-6 fatty acids which are often high in plant-based diets (see more information below), as well as trans fats, and alcohol. Insufficient energy (calories) or protein intake also decreases the conversion of ALA to EPA and DHA, as well as deficiencies in pyridoxine, biotin, calcium, copper, magnesium and zinc.
The Problem With Too Much Omega-6 Fatty Acid
How Does Omega-6 Block The Omega-3 Conversion?
Excess amounts of omega-6 fatty acid blocks the conversion of ALA into EPA and DHA by compeating for absorption.
What Foods Are High In Omega-6 Fatty Acid?
Omega-6 fatty acids which are found in many unhealthy foods that use vegetable oils including sunflower, safflower, cottonseed, corn and soy oil. Grapeseed oil is also higher in omega-6 fatty acid. Vegetarians and vegans are likely to have a higher intake of omega-6 fatty acids as they are also found in healthier foods that are prevalent in a plant-based diet including nuts and seeds and their butters.
What Is The Best Ratio of Omega-6 to Omega-3s?
Current estimations for the intake of omega-6s to omega-3s for the general population is a ratio of 10:1, meaning we eat 10 times more omega-6 fatty acids than omega-3s. Researchers have found a ratio of 2:1 is required for maximum conversion of ALA to both EPA and DHA.
The Problem With Trans Fats
What Are Trans Fats?
Trans fats are created through the hydrogenation of vegetable oils, which turns a liquid fat into a solid. Trans fats can be found in margarine, store-bought baked goods, crackers, fried foods including doughnuts, frozen pizzas and pie crusts and in many fast-food restaurants.
The Health Risks Associated With Trans Fats
Aside from decreasing the conversion of omega-3 ALA to EPA and DHA, trans fats have also been shown to increase our LDL or bad cholesterol and decrease our HDL good cholesterol. They have been strongly linked to increased risk of heart attack and stroke.
How Much Omega-3s Do Vegetarians and Vegans Need?
What Is the Recommended Dietary Intake for Omega-3s?
There have been no Recommended Dietary Intakes (RDIs) set for any of these essential fatty acids. Based on the available evidence we should be aiming for at least 650 milligrams per day of EPA and DHA combined. Although these are not official recommendations, they are the best we have based on the current research.
How Much Omega-3s Do We Need In Pregnancy?
A minimum amount of 300mg of DHA per day during pregnancy and lactation is recommended due to the strong link between DHA and baby’s brain health, and also potentially on mothers’ mood.
Can Vegetarians and Vegans Get Enough DHA and EPA?
Theoretically, without supplementation, those following a vegetarian diet would not able to reach the recommended targets for both EPA and DHA through diet alone. Even with the use of DHA-enriched eggs and some seaweed, the best a vegetarian could do is to meet the recommended target for DHA.
Though vegetarians may be in luck. Interestingly, some current research suggests that approximately 10% of DHA is retro-converted back to EPA. This suggests that if sufficient ALA and DHA are consumed, total EPA production would be sufficient and therefore all needs met.
But I Thought Vegetarians Were Healthier?
Vegetarian Diets and Decreased Risk of Chronic Disease
Plant-based diets have been associated with a decreased risk of chronic disease including a decreased risk of heart disease, likely due to lower cholesterol levels, as well as a decreased risk of obesity. So why do vegetarians enjoy a longer life expectancy and reduced risk of chronic diseases if they are at a higher risk of EPA and DHA deficiency?
ALA Omega-3s Are Cardioprotective
Epidemiologic and randomized controlled clinical studies have studied the effects of marine and plant sources of omega-3 fatty acids and have found that both marine and plant-derived omega-3 fatty acids have cardioprotective effects. So it seems there is a great unknown as to why we can’t find anything wrong with vegetarians despite them not getting direct sources of EPA and DHA.
Omega-3s in Seaweed
Seaweed As A Vegetarian Source of EPA and DHA
Seaweed and microalgae are the only plant-based sources of EPA and DHA – but at a very low concentration due to their extremely low total fat content (except in supplement form). Non-predatory fish and seafood get their DHA and EPA omega-3s by feasting on a diet rich in seaweed and algae. Note that blue-green algae (spirulina) are low in EPA and DHA and rich in omega-6’s.
How Much Omega-3 Is In Seaweed?
A 100 gram serving of macroalgea, or seaweed, provides about 100mg of EPA, but little DHA. This is more beneficial in countries where there is a large consumption of seaweed on a daily basis.
Can We Get Enough Omega-3 From Eating Seaweed?
Likely not, due to the very low fat content of seaweed. Omega-3 fatty acid supplement companies are coming up with new algae-based omega-3 supplements that contain direct sources of both EPA and DHA.
How Much Alpha-Linolenic Acid (ALA) Omega-3s Do Vegetarians and Vegans Need?
How Much ALA Omega-3 Do We Need?
There is no RDI set for ALA amounts set for vegetarians and vegans, but a general consensus in the nutrition world is at least 2 to 5 grams per day of ALA for males or 2 to 4 grams per day of ALA for females.
Omega-3 Food List for Vegetarians and Vegans
Below is a list of vegan sources of omega-3 ALA:
- 1 tbsp Flaxseed Oil – 7 grams ALA
- 1 tbsp Hemp Oil – 2.7 grams ALA
- 1 tbsp Flaxseed, ground* – 2.4 grams ALA
- 1/4 cup Walnuts, Persian, English – 2.3 grams ALA
- 1 tbsp Chia Seeds – 1.9 grams ALA
- 1 tbsp Canola Oil, organic – 1.2 grams ALA
- 1 cup Soy Beans, dried – 1.0 gram ALA
- 1/4 cup Walnuts, black – 0.85 grams ALA
- 1 cup So Good Essential Soy Milk – 0.6 grams ALA
- 100g Tofu, firm – 0.4 grams ALA
- 1/4 cup Edamame, shelled – 0.3 grams ALA
- 1/4 cup Pecans – 0.2 grams ALA
- 1 tbsp Hemp Hearts – 0.2 grams ALA
- 3 sheets Nori Seaweed – 0.01 grams ALA
*As a whole seed, very little of the Omega-3 fat is absorbed because the seed is very hard to digest by the body. Grinding the flaxseed improves the access and absorption of ALA.
Five Tips for the Best Conversion of Alpha-Linolenic Acid to EPA and DHA for Vegetarians and Vegans
Now that you know all the basic facts on getting enough omega-3s for vegetarians and vegans – here are my top 5 tips for maximizing the conversion of plant-based ALA to DHA and EPA.
- Limit intake of processed foods and deep-fried foods rich in trans fats and omega-6 fatty acids,
- For cooking at medium temperatures, use an oil high in monounsaturated fat such as olive oil in place of polyunsaturated omega-6 rich oils such as sunflower, safflower and grapeseed. Camelina Oil is best for high heat cooking,
- Eat other foods rich in monounsaturated fats including avocado, almonds, macadamias, cashews, and hazelnuts instead of foods high in polyunsaturated omega-6 fatty acids,
- Incorporate foods rich in omega-3 fatty acids into your diet each day including flaxseed oil, ground flaxseeds, chia, hemp seeds, green leafy vegetables, walnuts and organic soy products,
- Limit alcohol intake.
Vegetarian DHA Supplements
There are many situations were supplementation is extremely important. If you don’t think you can consume the recommended intake of ALA while following a plant-based diet, consider supplementing with an algae-based omega-3 supplement to ensure your DHA and EPA requirements are being met.
During pregnancy and lactation, it is extremely important that a mother is consuming a DHA based algae supplement with a minimum of 300mg DHA. Insufficient intake during pregnancy and lactation has been linked to poor brain development in infants, as well as maternal anxiety and postpartum depression. Here are two supplements that I generally recommend. It is best to speak to your health care provider before starting any supplementation regimen.
- NutraVege- Vegetarian Omega-3 Supplement contain EPA and DHA, available here
- Omega-Zen-3 – Available from Nutru
Website: Brenda Davis RD
Website: Dietitians Association of Australia
Rachel Dickens, The Conscious Dietitian, is a Registered Dietitian and Certified Diabetes Educator. She graduated with her Masters in Nutrition and Dietetics in 2010 from Griffith University. She strives to provide evidence-based nutrition information with a focus on plant-based nutrition, and share some of her favourite seasonal recipes and sustainable eating tips.