Old news: Omega-3 fatty acids improve brain function and eyesight; they also reduce heart disease, digestive issues, depression, osteoporosis, diabetes, high cholesterol, high blood pressure, arthritis, ADHD, cancer, and more. These are essential fatty acids, meaning that they are necessary for human health, but your body can’t make them (you have to get them from food).
New news: Not all omega-3s are created equal. At least not when it comes to cancer prevention, says a new study published in the Journal of Nutritional Biochemistry. The Canadian researchers found that omega-3 fatty acids that were marine-based—coming from fish, algae, or phytoplankton—offered eight times the protection at inhibiting tumor development and growth compared to plant-based omega-3s. Mice that had a highly aggressive form of breast cancer that affects 25% of women were given either plant-based or marine-based omega-3s. Compared to the plant-sourced omega-3s, the mice exposed to marine omega-3s had tumors that shrunk 60 to 70%, and they reduced the number of overall tumors by 30%.
While it’s always ideal to have human studies, this research is promising and points us to the types of omega-3s that have the most potent benefits for aggressive breast cancer.
ALA, EPA, and DHA Omega-3s: What’s the difference?
This difference boils down to a lot of chemistry that has to do with the number of carbons and double bonds that make up the chains for omega-3 fatty acids. What’s important to know is that alpha-linolenic acid (ALA) comes from plant sources such as flaxseed, soybean, walnuts, chia seeds, avocado, and so on. While your body can convert ALA into eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), you lose a lot in the process. This conversion mostly happens in your liver and what you end up with is estimated to be less than 15%. However, when you take EPA and DHA directly you absorb 95%—that’s a big difference.
How to make sure you get enough cancer protecting omega-3s.
I recommend that you eat fish two to three times per week and that you take 2 to 3 grams of a marine-based omega-3 supplement each day. You can also get EPA and DHA from omega-3 enriched eggs and milk.
Are there vegan and vegetarian options for marine-based omega-3s?
The best way to get DHA and EPA omega-3s is by eating fish and/or taking a fish-derived omega-3 supplement. This is a tricky one for vegans and vegetarians and a personal decision, but here are the facts: You can get DHA and EPA from algae and phytoplankton omega-3 supplements. But are algae and plankton vegan and/or vegetarian? The answer is yes—and no. Some species of algae can be both plant and animal. These algae can produce their own food by photosynthesis (like plants), but they can also eat other plants (like an animal). Phytoplankton is microscopic marine algae and can fall under the same ambiguous classification as algae.
Bottom line: More research is needed to find out if other health benefits are enhanced by different types of omega-3s, but for now it seems that marine-derived omega-3s are the best bet for breast cancer prevention.