Which is Better, Flaxseed Oil or Fish Oil
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Which is Better, Flaxseed Oil or Fish Oil?

Over the past few years, flaxseed oil has become more and more accepted as a new healthy oil. Both it and fish oil have been shown to prevent cardiovascular diseases, such as high blood pressure and coronary heart disease.

What Kind of Oil is Flaxseed Oil?

Flaxseed is the seed of flax and is rich in oil. The oil extracted from flaxseed is rich in alpha-linolenic acid. Walnuts, canola oil, and some nuts are also good sources of alpha-linolenic acid.

Flaxseed oil is the most important component, accounting for more than 92.8%, with 40-68% of ALA (alpha-linolenic acid), an omega-3 fatty acid with 18 carbon atoms and three double bonds.

ALA and linoleic acid (LA) in omega-6 fatty acids are essential fatty acids for humans, which cannot be synthesized by the body itself and must be obtained from food. When they enter the body, they can further produce arachidonic acid (AA), EPA, DHA, or hormone-like molecules.

In addition, cold-pressed flaxseed oil, like virgin olive oil and pressed bitter tea oil, contains some protein and fat-soluble trace components in addition to the oil. These trace components are about 478-594 mg per 100 grams of flaxseed oil, and they are phytosterols (83-91%), tocopherols (8-16%), squalene (0.2-0.9%), carotenoids (0.2-0.5%) and phenolic compounds (0.1-0.5%).

What is Fish Oil?

Fish oil is one of the most popular edible dietary supplements on the market and is obtained by extracting oil from fish tissue, mainly from fat-rich fish (such as herring, mackerel, or tuna) or fish liver (such as cod liver).

Fish oil is rich in very long-chain (n-3) fatty acids, with EPA and DHA accounting for about 30% of the fatty acids found in typical fish oils. Thus, 1 gram of fish oil capsule provides about 0.3 grams of EPA and DHA. the major omega-3 types in fish oil are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

Our common fish oil supplements contain 180 mg of EPA and 120 mg of DHA per capsule, and there are pharmaceutical-grade fish oils that have higher levels of EPA and are more suitable for people with high triglycerides, but the amount depends on the supplement and brand. Therefore, when clinicians refer to “fish oil,” they are usually referring to omega-3 fatty acids (also known as polyunsaturated fatty acids (PUFA)).

Similarities Between The Flaxseed Oil and Fish Oil

Similarities Between The Flaxseed Oil and Fish Oil

Omega-3 fatty acids include three main types. Eicosapentaenoic acid (EPA). Often referred to as the “vascular scavenger,” EPA helps the body synthesize chemicals related to blood clotting and inflammation, such as prostaglandins. Docosahexaenoic acid (DHA). Commonly known as “brain gold,” it is found primarily in the brain, eyes, and heart, as well as in breast milk.

EPA and DHA are known as long-chain omega-3 fatty acids, and AHA is also an important type of omega-3 fatty acid. Thus, both belong to the same family and both play similar roles in omega-3 fatty acids.

Heart Health

Supplementation with these oils has been shown to lower blood pressure levels in adults, even in small doses. In addition, omega-3 fatty acids are triglycerides that break down into smaller fatty acid units; they play a role in lowering plasma triglyceride levels, but increase cholesterol levels and are thought to have effective anti-arrhythmic effects.

Fish oil supplementation may also raise HDL (good) cholesterol and may lower your blood triglycerides by up to 30%. Flaxseed oil as a supplement may also have a beneficial effect on cholesterol levels. Some studies have shown that flaxseed oil may be effective in lowering LDL (bad) cholesterol and enhancing protective HDL cholesterol.

Protects The Skin

This is largely attributed to its omega-3 fatty acid content. Many studies have shown that fish oil supplements can improve many skin conditions, including dermatitis, psoriasis, and ultraviolet (UV)-induced skin damage. Similarly, flaxseed oil may help treat a variety of skin conditions.

A small study of 13 women found that a 12-week intake of flaxseed oil improved skin characteristics such as skin sensitivity, moistness, and smoothness.

Weight Loss

A meta-analysis of clinical trials published in 2019 in the American Journal of Clinical Nutrition showed that fish or fish oil rich in n-3 PUFA may reduce weight.

Anti-inflammatory Effects

Inflammation is associated with an increased risk of diseases such as diabetes and Crohn’s disease. Controlling inflammation can reduce the symptoms associated with these diseases.

A diet rich in omega-3s can reduce pro-inflammatory cytokines, which in turn are related to the omega-6/omega-3 ratio (i.e., a lower ratio reduces pro-inflammatory mediators. Studies have shown that fish oil has some anti-inflammatory properties due to the presence of omega-3 fatty acids in it.

However, the research on flaxseed oil and its effects on inflammation is complex. Although some animal studies have identified the anti-inflammatory potential of flaxseed oil, the results involving humans are mixed. Therefore, more research is needed to fully understand the anti-inflammatory effects of flaxseed oil in humans.

Difference Between The Flaxseed Oil and Fish Oil

Different Sources

Fish oil comes from fatty fish and other animal foods, while flaxseed oil is found mainly in plants. Flaxseed oil usually contains 45-55% alpha-linolenic acid, which can be converted into EPA and DHA in small amounts. although alpha-linolenic acid is a classical essential fatty acid, animals cannot synthesize linolenic acid themselves because of the lack of Δ-15 fatty acid dehydrogenase in their bodies, but it can be metabolized into other longer-chain, more unsaturated omega-3 fatty acids in the human body.


ALA is not biologically active and needs to be converted to EPA and DHA to be used for other purposes rather than just storing energy like other types of fats. And the conversion process from ALA to EPA and DHA is inefficient in humans. one study found that in adults, only 5% of ALA is converted to EPA and less than 0.5% to DHA. the conversion rate depends on the appropriate levels of other nutrients, such as copper, calcium, magnesium, zinc, iron, and vitamins B6 and B7.

Physiological Functions

There is extensive evidence that ALA is an effective neuroprotective agent against focal and global ischemia in animal models. In a mouse model of total ischemia, where hippocampal pyramidal neuronal death is primarily caused by glutamate excitability, ALA was found to exert a more significant and reproducible profound protective effect than EPA and DHA.

It was shown that ALA increases brain-derived neurotrophic factor (BDNF), which performs different functions in the brain, including neuronal maintenance, learning and memory, neuronal survival, and neuronal formation.

Which Oil is More Suitable to Choose?

Are You a Vegetarian?

Vegetarians will also be concerned about raw materials. Flaxseed oil with plant-based ingredients may also be more suitable for vegetarians or vegans.

Do You Have a History of Allergies?

If you are allergic to seafood, especially fish, be aware that some fish oil supplements, for example, may contain small amounts of fish or shellfish protein. Many fish oil supplements have a warning on the bottle”. Avoid using this product if you are allergic to fish or shellfish.” For those who are allergic to fish or shellfish, flaxseed oil may be a more appropriate choice than fish oil of animal origin.

Food Safety Risks

Deep-sea fish may carry marine contaminants that can lead to food poisoning. Fish oil supplements also have some side effects, usually minor gastrointestinal problems such as gas, indigestion, or diarrhea. alpha-linolenic acid content is relatively safe and well-tolerated and can be used in daily cooking or added to the daily diet.

Lipid Abnormalities

If there is obvious dyslipidemia, especially those with high triglycerides, it is recommended to choose fish oil with high EPA content to increase liver mitochondria and peroxy isomerization-oxidation to reduce lipogenesis in the liver. EPA and DHA can inhibit the esterification of other fatty acids, which can better reduce triglycerides and play an anti-inflammatory and cardiovascular protective role.