The Oil That Contains The Most Amount Of Omega-3s Isn't Fish Oil

It's easy to assume that fish oil automatically reigns supreme when it comes to omega-3 fatty acids. But there's a plant-based contender that often flies under the radar and its concentrated form makes it exceptionally rich in these essential fats. Enter flax oil — better known as flaxseed oil — the powerhouse that overtakes fish oil when it comes to sheer omega-3 content per serving. Just one tablespoon of flaxseed oil delivers 8.5 grams of an omega-3 fatty acid called alpha-linolenic acid (ALA), making it one of the richest plant-based sources available.

Flaxseeds are among the top foods high in omega-3s that aren't fish, which makes the oil a far more concentrated option. The reason flaxseed oil eclipses fish oil and fish with high levels of omega-3 fatty acids lies in its composition. Flaxseed oil contains roughly 55 % ALA and is six times richer in omega-3 linseed oil than most fish oils. Fish oils are sources of other types of omega-3s, such as EPA and DHA. Due to the high ALA content of flaxseed oil, a single tablespoon can outperform fish oil in terms of raw omega-3 quantity.

However, given that ALA is plant-based, the human body must enzymatically convert this type of acid into EPA and DHA. In this process, it is estimated that the body only retains about 10 to 15% of ALA. By contrast, fish oil provides more bioavailable sources of omega-3s, allowing you to reap the benefits more efficiently than ALA. That said, there are still many benefits to flaxseed oil that make it a viable source of healthy fat in your diet. 

Flaxseed oil offers some distinctive benefits beyond its high ALA content. Unlike fish oil, it contains plant-based substances called lignans, which have been proven to help with cancer treatment and prevention. Additionally, flaxseed oil has been shown to support gastrointestinal health, such as easing constipation or improving bowel consistency.

Clinical studies also highlight some interesting comparative outcomes. For instance, for patients with type two diabetes and coronary heart disease, flaxseed oil was more effective than fish oil at lowering serum insulin and high sensitivity C-reactive protein, a marker of inflammation. From a practical standpoint, flaxseed oil is a safe option for vegetarians, vegans, and individuals with a shellfish allergy, the most common allergy in adults. It avoids the risk of mercury consumption, which is present in many types of fish. Fish oil may also lose some of its nutrients and even become rancid as a result of oxidation. 

While flaxseed oil offers the most omega-3s by quantity, fish oil maintains an advantage as a direct source of EPA and DHA, more readily usable by the body. However, flaxseed oil shines for its plant-based profile, additional beneficial compounds, digestive support, and even promising results in lowering inflammation and insulin markers. Ultimately, the right choice for you depends on your priorities, be it nutritional value, dietary preferences, gut health, sustainability, or anti-inflammatory benefits. To find the best fit, discuss your options with a naturopathic doctor or healthcare provider.