How much omega-3 each individual needs per day varies depending on their age, sex, and several health factors. For example, people who are pregnant or lactating may need to add more omega-3 to their diet.

People give omega-3 fatty acids a lot of attention due to their health benefits. Fatty fish, nuts, and seeds are rich in omega-3s.

Omega-3s are important parts of the body’s cell membranes. They help with the functioning of the heart, lungs, immune system, and hormone system.

There are three types of omega-3 fatty acids:

  • docosahexaenoic acid (DHA)
  • eicosapentaenoic acid (EPA)
  • alpha-linolenic acid (ALA)

DHA levels are especially high in the eye, brain, and sperm cells. EPA may have certain benefits for reducing inflammation. The body breaks down ALA into EPA and DHA, but the conversion rate is low. For this reason, people should include all three omega-3s in their diet.

Fatty fish are high in DHA and EPA. Plant sources are high in ALA. If a person does not get enough of each type of omega-3 from their diet, they might consider taking a supplement.

This article explores the recommended intake of omega-3s for different people to achieve optimal health.

Several national organizations have released guidelines for omega-3 intake, but they vary considerably.

As such, there is no absolute rule about how much omega-3 a person needs.

However, research does suggest that different groups of people need different amounts, and higher intakes of omega-3 can be helpful for certain health conditions. We discuss the dietary needs below.

Adult males and females

According to the National Institutes of Health (NIH)Trusted Source, there is not enough data available to work out a recommended daily allowance of omega-3 for healthy adults. There are also no specific recommendations for EPA and DHA separately.

Other sources have estimated an adequate intake (AI) of omega-3s. AI is the amount a person needs to ensure nutritional adequacy.

For an AI of ALA, the NIHTrusted Source recommends 1.6 grams (g) for males and 1.1 g for females.

Pregnancy, breastfeeding, and children

People should add more omega-3 to their diet when pregnant and lactating.

The Food and Drug Administration (FDA)Trusted Source advises people who might become pregnant, those who are breastfeeding, and young children should include more fish in their diets every week.

The FDA recommends that those who are pregnant or breastfeeding eat 8 to 12 ounces of low mercury fish every week to benefit fetal growth and development.

Infants up to the age of 1 year should consume 0.5 gTrusted Source total of omega-3s. Human milk contains ALA, DHA, and EPA for breastfed infants.

A comprehensive review from 2018 reports that omega-3 may have benefits for heart disease.

A 2002 studyTrusted Source recommends that people with cardiovascular disease consume around 1 g of EPA plus DHA per day, preferably from oily fish. However, they can speak with their doctor about taking supplements. That said, updated guidelines are needed.

Researchers have conducted many studies to evaluate the effects of taking omega-3 supplements on heart disease.

One 2017 reviewTrusted Source found that there was a modest decrease in death in people with established coronary heart disease as well as those with heart failure.

However, the results are mixed with those of a large study from 2018. In it, researchers concluded that DHA and EPA supplements may have little effect, while ALA might have a small effect.

In a 2024 study, omega-3 supplementation was associated with an increased risk of developing atrial fibrillation (AFib) and stroke. However, complications from these conditions, such as cardiovascular events and death, were decreased in this group.

This study indicates the need for further research on omega-3 and its effects on cardiovascular health.

Some studies suggest taking omega-3 supplements may help with symptoms of depression.

One small-scale 2015 study including young adults with depressive symptoms reported that a group receiving 1.4 g of DHA plus EPA every day had a significantly lower depression status than a placebo group after 21 days.

A 2024 review of studies compiling the research on omega-3s having antidepressant effects finds the results to be inconsistent, with some studies finding a significant reduction in depressive symptoms while others failed to show any effects. Further research is needed.

Omega-3 supplements may also have potential as a future treatment for Alzheimer’s disease.

A 2018 reviewTrusted Source found that omega-3s may be beneficial in early Alzheimer’s disease when there is only a slight impairment in brain function.

A 2022 review confirmed that omega-3 supplements increased blood flow in the brain. Study participants experienced improvements in learning, memory, and cognitive well-being. In addition, a 2024 studyTrusted Source found that omega-3 increased thinking ability in older adults.

However, more data is needed to support using omega-3 supplements in more advanced cases of Alzheimer’s disease.

Many studies have examined the effects of omega-3 supplementation on certain cancer types.

One 2017 studyTrusted Source reports that combining omega-3 and vitamin D supplements increased cell death in certain subtypes of breast cancer cells.

In a 2016 reviewTrusted Source of omega-3s and prostate cancer, some researchers found a link between higher omega-3 intake and reduced death from prostate cancer.

However, present research is very mixed on omega-3s and cancer risk. Some studiesTrusted Source have even indicated that omega-3 supplementation has been associated with an increased risk of prostate cancer.

There is no established upper limit of omega-3 intake. According to the NIH, the FDA has suggested that people should take no more than 5 g per dayTrusted Source of DHA and EPA combined.

Over long periods, scientists say that omega-3 supplementation can reduce immune system function because it lowers the body’s inflammatory responses.

High doses of omega-3 may also increase bleeding time. Therefore, people who take blood-thinning drugs should take caution and talk with their doctor before starting to take an omega-3 supplement.

There are few known symptoms of omega-3 deficiencies. Doctors have found links between a deficiency of essential fatty acids, including omega-3 and omega-6, and symptoms of dermatitis and rough, scaly skin.

Researchers do not knowTrusted Source whether there is a certain threshold of DHA and EPA in the body that could raise the risk of neurological or immune dysfunction.

In the United States, omega-3 deficiency is very rareTrusted Source.

If a person cannot get enough omega-3 in their diet, they might consider taking a supplement. Speak with a doctor before taking any new dietary supplements.

The ingredients of omega-3 supplements vary widely. People may wish to examine the product label to see what exactly their supplement contains.

The amount of each ingredient can vary between batches of the same product because the FDA does not regulate the quality of supplements as it does drugs.

A typical omega-3 supplement provides around 1 gTrusted Source of fish oil and varying doses of EPA and DHA.

Long-chain omega-3 EPA and DHA, which have the most well-researched health benefits, are present in fish oil, krill oil, and cod liver oil supplements.

Plant-based algal oil providesTrusted Source around 0.1 g to 0.3 g of DHA, and some also contain EPA. Other plant-based supplements, such as flaxseed capsules, only provide ALA fatty acids.

While seafood can contain heavy metals, scientists have not found these in omega-3 supplements since the manufacturers remove them during processing and purification.

People can find omega-3 supplements in health stores or choose from a range of brands in online stores.

The amount of omega-3 a person needs depends on their age, sex, and health status. People can eat oily fish twice per week to get adequate EPA and DHA, and they can include plant-based sources of ALA in their diet.

Health experts recommend that people not exceed 5 g of omega-3 in a day unless otherwise directed by a medical professional.

If a person does not eat fish, taking an omega-3 supplement might be a good idea. Be sure to read a supplement’s label carefully and talk with a doctor before taking any new supplements.