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When you think of algae, you make picture the greenish film that sometimes develops on ponds and lakes.
But you may not know that this marine organism is also cultivated in laboratories for its unique oil, which is packed with omega-3 fatty acids. These fats are linked to many health benefits.
While fish oil also supplies omega-3s, algae oil may provide a great plant-based alternative if you don’t eat seafood or can’t tolerate fish oil.
Algae itself includes 40,000 species that range from single-celled microscopic organisms known as microalgae to kelp and seaweed. All types rely on energy from sunlight or ultraviolet (UV) light and carbon dioxide (
This article explains everything you need to know about algae oil, including its nutrients, benefits, dosage, and side effects.
Which nutrients are in algae oil?
Certain species of microalgae are especially rich in two of the main types of omega-3 fatty acids — eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). As such, these species are grown for their oil.
One study found that the percentage of omega-3s in microalgae is comparable to that of various fish (
Yet, it’s easy to increase the amount of omega-3s in algae by manipulating their exposure to UV light, oxygen, sodium, glucose, and temperature (
Their oil is extracted, purified, and used in a variety of ways, including to enrich animal, poultry, and fish feed. When you eat eggs, chicken, or farmed salmon that’s enhanced with omega-3s, it’s likely t these fats come from algae oil (
Plus, this oil serves as a source of omega-3s in infant formula and other foods, as well as plant-based vitamins and omega-3 supplements (
Levels of omega-3s in algae oil
|Nordic Naturals Algae Omega|
(2 soft gels)
|Source Vegan Omega-3s|
(2 soft gels)
(1 soft gel)
|Nature’s Science Vegan Omega-3|
(2 soft gels)
|Nature’s Way NutraVege Omega-3 Liquid|
(1 teaspoon — 5 ml)
Like fish oil supplements, those made from algae oil vary in their amounts and types of omega-3 fats, as well as their serving sizes. Thus, it’s best to compare labels when shopping.
You can also buy algae oil as a cooking oil. Its neutral flavor and very high smoke point make it ideal for sautéing or high-heat roasting.
However, while it’s an excellent source of healthy unsaturated fats, culinary algae oil doesn’t contain any omega-3s because these fats aren’t heat-stable.
Oil extracted from algae is rich in the omega-3 fats EPA and DHA, though specific amounts vary between brands. It’s not only used as a dietary supplement but also to enrich infant formula and animal feed.
What are omega-3s?
Omega-3 fatty acids are a family of polyunsaturated fats found in plants and fish. They supply essential fats that your body can’t make on its own, so you have to get from your diet.
Several types exist, but most research focuses on EPA, DHA, and alpha-linolenic acid (ALA) (8).
Omega-3s are critical to the structure and function of cell membranes throughout your body. Your eyes and brain have especially high levels of DHA (8).
The best sources
Both EPA and DHA are found in fish and marine foods. Herring, salmon, anchovies, sardines, and other oily fish are the richest dietary sources of these fats (12).
Omega-3s are necessary for various processes in your body. You can get ALA from many plant foods, while EPA and DHA are found in fish and marine plants like seaweed and algae.
Algae oil vs. fish oil
In one study, algae oil supplements were found to be nutritionally equivalent to cooked salmon and work the same way as fish oil in your body (
Furthermore, a 2-week study in 31 people revealed that taking 600 mg of DHA from algae oil per day raised blood levels the same percentage as taking an equal amount of DHA from fish oil — even in a vegetarian group with low DHA levels at the start of the study (16).
Just as the fatty acid composition of fish depends on their diet and fat stores, the fat in algae fluctuates based on the species, stage of growth, seasonal variations, and environmental factors (
All the same, scientists are able to select and grow certain strains that are higher in omega-3s. As algae grows very quickly and doesn’t contribute to overfishing, it may be more sustainable than fish oil supplements (
What’s more, because it’s grown under controlled conditions and purified, algae oil is free from toxins that may be present in fish and fish oils (
Algae oil is nutritionally similar to fish oil, and studies have confirmed that they exert the same effects in your body. Additionally, algae oil is plant-based, may be more sustainably sourced, and likely results in fewer taste complaints.
Potential health benefits
Research reveals that people with higher levels of omega-3 fats have a lower risk of certain health conditions.
This link appears strongest in people who eat fish rather than those who take supplements. Still, evidence suggests that supplements can be helpful.
Most studies examine fish oil rather than algae oil. However, studies using the latter reveal a significant increase in blood DHA levels, even in vegetarians or those who don’t eat fish — so it’s likely just as effective (
May support heart health
Omega-3 supplements may reduce blood pressure and improve blood vessel function, which may lower your risk of heart attack or stroke (
Omega-3s have likewise been shown to reduce triglyceride levels.
In addition, a recent review of 13 clinical trials in over 127,000 people noted that taking omega-3 supplements from various marine sources reduced the risk of heart attack and all heart disease, as well as death from these conditions (
May reduce depression
People diagnosed with depression often have lower levels of EPA and DHA in their blood (
Correspondingly, an analysis of studies including more than 150,000 people found those who ate more fish had a lower risk of depression. The lower risk may be partly due to a higher intake of omega-3s (
People with depression who receive EPA and DHA supplements often notice an improvement in their symptoms. Interestingly, an analysis of 35 studies in 6,665 people determined that EPA is more effective than DHA for treating this condition (
May benefit eye health
If you experience dry eyes or eye fatigue, taking an omega-3 supplement may minimize your symptoms by decreasing your tear evaporation rate (
In studies in people who experience eye irritation from wearing contacts or working on the computer for more than 3 hours per day, taking 600–1,200 mg of combined EPA and DHA eased symptoms in both groups (
Omega-3s may also have other eye benefits, such as fighting age-related macular degeneration (AMD), a condition that can cause vision loss — though research is mixed.
A study in nearly 115,000 older adults noted that higher dietary intakes of EPA and DHA may prevent or delay intermediate — but not advanced — AMD (
May reduce inflammation
Omega-3s may inhibit compounds that trigger inflammation. Thus, they may help combat certain inflammatory conditions.
In a 12-week study in 60 women with rheumatoid arthritis (RA), taking 5,000 mg of omega-3s from fish oil each day reduced the severity of symptoms. The women also had fewer reports of pain and tender joints, compared with those taking a placebo (
Algae oil supplements may aid heart, brain, and eye health, as well as fight inflammation. Studies show that both fish and algae oil increase omega-3 levels in your body.
Dosage and how to take it
If you don’t eat fish at least twice per week, you may be low in these fats. Thus, a supplement may help compensate.
Keep in mind that algae oil supplements provide varying amounts of these fatty acids. Try to choose one that provides at least 250 mg of combined EPA and DHA per serving. They can be found in specialty stores and online.
If you have high triglycerides or blood pressure, consider asking your healthcare provider if you should take a higher dose.
While you can take it at any time of day, most manufacturers recommend supplementing with a meal — especially one that contains fat, as this macronutrient aids absorption.
Remember that the unsaturated fats in algae oil supplements can oxidize over time and go rancid. Be sure to store gels or capsules in a cool, dry place, refrigerate liquid supplements, and discard any that smell bad.
You should choose an algae oil supplement with at least 250 mg of combined EPA and DHA unless your health practitioner recommends a higher dose. It’s best to take it with food and store it according to the manufacturer’s instructions.
Possible side effects
Omega-3 supplements are generally considered safe. They have minimal side effects unless you take very high doses.
There is no established upper limit, but the European Food Safety Authority claims that taking up to a 5,000-mg combined dose of EPA and DHA daily appears to be safe (8).
Omega-3 supplements may also interact with some medications, so it’s always good to talk to your healthcare provider beforehand.
In particular, omega-3s may have blood-thinning effects and can affect anticoagulant medications like warfarin, increasing your risk of bleeding (8).
Algae oil is safe for most people and has fewer reported digestive effects than fish oil. It’s always best to consult your healthcare provider about dosage and potential interactions with your medications.
The bottom line
Algae oil is a plant-based source of EPA and DHA, two omega-3 fats that are essential for your health.
It provides the same benefits as fish oil but is a better choice if you don’t eat fish, follow a plant-based diet, or can’t tolerate the taste or aftereffects of fish oil.
Taking algae oil may reduce your risk of heart disease, fight inflammation, and support brain and eye health.