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Omega-3 Fatty Acids: Benefits for the Heart, Brain, Joints & More
May 2, 2024
Omega-3s (or omega-3 fatty acids) have earned a great deal of respect in the health community, but do you know what omega-3s are? What are the benefits of omega-3s, and could you be deficient in these fatty acids?
We’ll unpack these questions one by one, but let’s start by saying that omega-3 fatty acids are crucial nutrients for overall health. Your body doesn’t produce omega-3s on its own, which means they are “essential fatty acids” — you have to consume them regularly from food and supplement sources.
The most commonly known health perk of omega-3s is a reduced risk of heart disease, but they also assist in fetal development, vision, skin health, weight management and a lot more. Let’s look below at why you need them and how to effectively get more.
What Are Omega-3 Fatty Acids?
Omega-3s are a specific type of polyunsaturated fatty acid. That means they contain more than one double bond in their chemical structure. The “3” refers to where in the chemical structure the first double bond occurs.
Why do you need omega-3 fatty acids? Your body is able to synthesize saturated fatty acids, but you don’t have an enzyme that allows you to stick a double bond in the right spot to create omega-3s yourself.
In other words, your body can’t make these fats on its own, so you need to get them from your diet or from omega-3 supplements (such as omega-3 fish oil or capsules).
Your body also needs omega-6s, another type of fatty acid, to function properly and prevent disease. Omega-6s come in some form of linoleic acid. They are found in vegetable oils, safflower oils, meat, poultry and eggs.
Unfortunately, these are found in much more abundance than omega-3s in the standard American diet, although your body craves a 1:1 ratio to keep inflammation low. Most modern diets contain a ratio closer to 20:1 or 30:1 omega-6 to omega-3 fatty acids. It’s important to learn how to balance omega-3s, omega-6s and omega-9s.
Types of Omega-3
Alpha-linolenic Acid (ALA)
This plant-based omega-3 is found in green, leafy vegetables; flaxseeds and chia seeds; and canola, walnut and soybean oils (although those rancid oils are not ones I generally recommend). ALA is known as a short-chain omega-3. This means your body has to convert it into longer-chained EPA and DHA to synthesize it. This process is rather inefficient, and only about 10 percent of the ALA you consume is converted to the long-chain version your body needs (although this percentage is slightly higher for women).
Eicosapentaenoic Acid (EPA)
EPA is a 20-carbon fatty acid found in oily fish, algae oil and krill oil. Your body is able to synthesize this molecule in its original form. EPA and DHA are the omega-3s your body needs in high quantities to achieve the benefits they offer.
Eicosatetraenoic Acid (ETA)
ETA is a lesser-known omega-3 fatty acid that also contains 20 carbons, like EPA, but only four bonds instead of five. It is found richly in roe oil and green-lipped mussel. Not only is it anti-inflammatory, like the other omega-3s, but ETA can also limit your body’s production of the inflammatory omega-6 fatty acid arachidonic acid (ARA). In fact, ETA redirects the enzyme that normally creates ARA to convert it to EPA instead.
Docosahexaenoic Acid (DHA)
This 22-carbon molecule is also found in oily fish, krill oil, algae oil and omega-3 fish oil supplements. Your body converts some DHA molecules back to EPA in order to keep them at fairly equal levels if you consume more DHA.
Benefits
1. Good for Heart Health
One of the most well-known omega-3 benefits is the way they positively affect risk factors associated with heart disease and stroke, the leading causes of death worldwide. Studies show that adults who eat diets rich in fish (such as the pescatarian diet) tend to have low instances of these diseases.
The U.S. Food and Drug Administration has approved two omega-3 supplement treatments for high triglycerides. One contains just one compound, and the other contains two of the animal-based omega-3 fatty acids: EPA and DHA.
While some studies and analyses have found no evidence indicating omega-3s significantly reduce risk of stroke or heart attacks, other reviews disagree.
Here is what we do know about cardiovascular disease risks, including strokes and heart attacks, and omega-3s:
- Lowering High Triglycerides: The American Heart Association recognizes that the highest amount of omega-3s are generally needed for people with high triglycerides, a major risk factor for heart disease. Use of omega-3 supplements has been associated with lowered triglyceride levels in patients with or without other diseases.
- Regulating Cholesterol: Research finds omega-3 can affect cholesterol levels by raising HDL (“good”) cholesterol, although some results also find a slight increase in LDL “bad” cholesterol, too.
- Lowering High Blood Pressure: One study found that three servings of salmon each week successfully lowered blood pressure in young, overweight people over an eight-week period. While this is not definitive proof that omega-3s lower blood pressure, it’s an encouraging preliminary result. The DASH diet used to control hypertension also emphasizes fish for heart health.
- Preventing Plaque Buildup: Keeping arteries clear of damage, omega-3s may aid your body in preventing plaque buildup responsible for hardening and restriction of the arteries.
- Reduce Metabolic Syndrome Symptoms: The cluster of risk factors known as metabolic syndrome includes abdominal obesity, high blood sugar, high triglycerides, high blood pressure and low HDL cholesterol. These risk factors are indicative of a high chance you might develop heart disease, stroke or diabetes. Multiple studies have found omega-3 supplements can help improve symptoms of metabolic syndrome and may protect you from the related diseases.
- Preventing Blood Clots: It’s possible omega-3s help your platelets not clump together, aiding in the prevention of blood clots that can lead to a stroke.
2. May Fight Mental Disorders and Decline
There are a number of conditions related to brain and mental health that seem to improve when individuals get good omega-3s.
- Depression and Anxiety: Some research suggests that people who regularly get large amounts of omega-3s are less likely to be depressed than those who are deficient. Several studies have demonstrated that people suffering signs of depression and/or anxiety often see improvements after adding an omega-3 supplement to their routines, even in double-blinded, randomized, controlled trials. At least one study comparing a common depression medication found omega-3 supplements to be just as effective in combating depression symptoms.
- ADHD: Certain studies, but not all, comparing omega-3 levels in children have discovered those with ADHD diagnoses have lower blood omega-3 fatty acids compared to healthy comparison subjects. Limited but promising results seem to agree that there is likely some effectiveness of omega-3s for managing ADHD symptoms.
- Schizophrenia: One meta-analysis investigating the link between omega-3s and schizophrenia found modestly positive results with higher consumption, specifically in the early stages of the disease.
- Bipolar Disorder: Also known as manic depression, bipolar disorder is a complex and sometimes debilitating condition. There is some evidence that omega-3s can assist bipolar sufferers by stabilizing their moods.
- Other Mental Illness and Behaviors: Some studies have found correlations between omega-3s and a decrease in violence, antisocial behavior and borderline personality disorder.
- Alzheimer’s and Age-Related Mental Decline: Small clinical trials have seen potential neuroprotective effects of omega-3 fats on people suffering from dementia, age-related mental decline and even Alzheimer’s disease. It seems that increased omega-3s in the blood may potentially help to slow or even reverse some cognitive decline, however not all studies show this to be true.
3. Reduce Inflammation
One reason omega-3 fatty acids may be so beneficial to many aspects of health could be that they help decrease system-wide inflammation, the root cause of most diseases. By eating a nutrient-dense and anti-inflammatory diet, you give your body its best chance to fight disease like it was designed to do.
In particular, recent evidence has found that supplementing with omega-3s may reduce some inflammation caused by fat accumulation in non-alcoholic fatty liver disease.
An animal study involving the omega-3 ETA discovered that subjects experienced a drop in overall inflammation similar to that caused by non-steroidal anti-inflammatory drugs (NSAIDs) but without the dangers of NSAIDs, such as gastrointestinal side effects.
The study authors also pointed out that eicosapentaenoic acid seems to be even more potent for supporting normal immune responses than the conventional omega-3s found in fish oil supplements (EPA/DHA).
4. Linked to Preventing and Managing Autoimmune Diseases
Characterized by the immune system attacking healthy cells, mistaking them for foreign intruders, autoimmune conditions include diseases such as type 1 diabetes, lupus, rheumatoid arthritis, ulcerative colitis, multiple sclerosis, leaky gut syndrome and many more.
Multiple studies have found links between high omega-3 intake and a decreased risk for autoimmune diseases or an improvement in autoimmune disease symptoms. Some of these suggest the best protective effect comes when omega-3 fatty acids are consumed in the first year of life.
5. Associated with Lowered Cancer Risks
Through several epidemiological studies, in which researchers observe trends in large population samples over time, it seems possible that adequate intake of omega-3 fats may be associated with a lowered risk of certain cancers.
People who consume more long-chain omega-3s (DHA and EPA) seem to have a reduced risk of colorectal cancer, according to observations in Scotland and China.
After a large number of lab studies found that omega-3 fatty acids may be effective in slowing or reversing the growth of hormonal cancers, namely prostate cancer and breast cancer cells, animal and human epidemiological studies have been conducted to see whether this effect occurred in real-life scenarios. However, additional information on this topic is still warranted.
The evidence is somewhat conflicting in some reports, but there is some evidence to suggest breast cancer and prostate cancer may be potentially slowed (or the risk reduced) in people who eat a lot of oily fish and possibly those who supplement with omega-3.
A lab study in 2014 found that the pancreatic cancer-fighting impact of curcumin, the active ingredient in turmeric, may be enhanced when combined with omega-3 fatty acids, encouraging further studies in animal and human models to investigate the potential of this combination.
6. May Support Healthy Bones and Joints
The issue of osteoporosis is a major factor for older adults, affecting hundreds of millions of people worldwide and resulting in osteoporotic fractures once every three seconds.
Essential fatty acids, including omega-3s, are recognized in scientific research as able to increase the amount of calcium you absorb from your gut (partly by enhancing the vitamin D effect) and improve the strength of your bones and synthesis of bone collagen.
Small, randomized, controlled trials have seen an increase in bone density in older people with osteoporosis when supplementing with EPA compared with placebo groups, whose bone density decreased over time.
Additionally, studies suggest that omega-3s can help people dealing with arthritis by lowering swelling and inflammation of tender joints.
Another study found that due to their potential anti-inflammatory and antioxidant activity, omega-3s may also help improve exercise performance and assist in recovery.
7. Might Improve Sleep Quality
It’s possible that children, in particular, may experience problems with sleep when they don’t get enough omega-3 fatty acids in their diets. In adults, low omega-3 levels are associated with obstructive sleep apnea.
One reason for this may be that low omega-3s are linked to lower levels of melatonin, the hormone partly responsible for helping you to get to sleep in the first place.
The good news is that sleep deprivation symptoms, such as poor memory and learning capacity, tend to improve in patients treated with omega-3 supplementation, according to some studies.
8. Beneficial for Infant and Child Development
It seems that infancy and childhood are some of the most important periods of time in a person’s life to get plenty omega-3s in the diet, probably because of the amount of long-chain fatty acids found in the brain and retina. It’s crucial for developing babies and children to get a good amount of DHA and EPA so their brains and eyes develop fully and properly.
Pregnant moms need to be particularly aware of this, because children with mothers who supplement with omega-3s during pregnancy score better on mental processing, psychomotor, hand-eye coordination and audial processing tests at nine months and four years of age. These children also seem to have lowered ADHD risk.
While breast milk is a great source of omega-3 fats for nursing infants (as long as mom is getting a lot herself), formulas don’t always contain enough of the nutrient. DHA-fortified formula, on the other hand, can help formula-fed babies with both visual and cognitive development.
It’s possible that supplementing with EPA, ETA and DHA could even help prevent cerebral palsy, autism spectrum disorders and asthma in some children.
9. May Fight Menstrual Pain
PMS cramps affect about 75 percent of menstruating women and, for some of them, become debilitating and affect work or home life. However, research shows that supplementing with omega-3s significantly affects menstrual symptoms, making them milder.
In fact, one study comparing ibuprofen and fish oil supplements during adolescent PMS found that the supplement actually worked better to relieve menstrual pain than the standard medication.
10. Linked to Lowered Macular Degeneration Risk
Your retina contains quite a bit of DHA, making it necessary for that fatty acid to function. The National Eye Institute, part of the National Institutes of Health, concludes that there is “consistent evidence” suggesting long-chain polyunsaturated fatty acids DHA and EPA are necessary for retinal health and may help protect the eyes from disease.
In particular, adequate omega-3 intake is significantly correlated with a lower risk of age-related macular degeneration, the leading cause of blindness in those over 60 years old.
11. Support Healthy Skin and Slow Aging
In some of the same ways omega-3 fatty acids protect your bone density, they can also help your skin stay beautiful from the inside out. DHA and EPA both benefit your skin by managing oil production and naturally slowing aging.
Some studies even show omega-3 benefits the skin by helping prevent acne and related inflammatory conditions.
Foods
Oily fish are the best food source of omega-3s. There are plant sources, too, including some nuts and seeds, but they contain ALA, which takes a lot of energy for your body to convert to EPA and DHA.
It’s ideal to get your fatty acids from omega-3 foods since they provide other nutrients that benefit health as well, such as vitamin K, folate, phosphorus, etc.
Top omega-3 foods include:
- Atlantic mackerel
- Salmon fish oil
- Cod liver oil
- Walnuts
- Chia seeds
- Herring
- Wild-caught salmon
- Flaxseeds
- Albacore tuna
- White fish
- Sardines
- Hemp seeds
- Natto
- Egg yolks
What about flaxseed oil? Flaxseed oil is very high in ALA, with over 7 grams of ALA per tablespoon. However, ALA isn’t absorbed as well as DHA and EPA, so it’s not the ideal source.
That said, it’s still a healthy oil and good source of fats, so it can be used in moderation to supplement a balanced diet.
Supplements and Dosage
There are no official guidelines for the proper amount of omega-3s you should consume each day.
However, most organization agree that at least two servings of a 3.5-ounce serving of fish (preferably oily) each week is a good start. That equals about 500 milligrams of EPA/DHA each day. In general, most health organizations agree 250–500 milligrams of EPA and DHA combined each day is a reasonable amount to support healthy individuals.
The omega-3 adequate intake recommendations provided in the Dietary Reference Intakes developed by the National Academy of Medicine is actually higher. These adequate intake figures only apply to ALA, as the Academy didn’t specify intake recommendations for EPA, DHA or other omega-3s:
- Birth to 12 months: 0.5 g
- 1 to 3 years: 0.7 g
- 4 to 8 years: 0.9 g
- 9 to 13 years: 1.2 g for boys; 1.0 g for girls
- 14 to 18 years: 1.6 g for boys; 1.1 g for girls; 1.4 g for pregnancy; 1.3 g for lactation
- 19 to 50 years: 1.6 g for men; 1.1 g for women; 1.4 g for pregnancy; 1.3 g for lactation
- 51 years and over: 1.6 g for men; 1.1 g for women
However, people with heart problems (or those with a high risk of heart disease), depression, anxiety and cancer (and possibly more conditions) may benefit from higher doses — up to 4 grams per day, although values do vary.
If you follow a vegan diet, it’s smart to supplement with an ALA-based vegan omega-3 capsule/oil. You will probably need a higher dose because of the way your body processes the medium-chain fatty acid when you take vegan omega-3.
Some high-quality omega-3 supplements have lower amounts of EPA/DHA but accompany them with digestive enzymes. While it looks counterintuitive on a nutrition label, this is often done because there is debate about how much of the omega-3s you actually absorb from dietary supplements when taken alone.
By coupling omega-3s with a digestive enzyme blend, you are likely able to absorb more of the nutrient without having to consume as many grams.
Is it good to take omega-3 every day? In most cases, yes. It’s generally safe to consume on an ongoing basis, unless your doctor tells you otherwise.
Deficiency Symptoms
It’s believed that most people don’t get enough of these fats, meaning that omega-3 deficiency is common.
In 2009, the Harvard School of Public Health published a review of individual risk factors that are attributable to specific deaths. By its estimates, low omega-3 intake is eighth on the list of the most serious risk factors that contribute to death, labeling it responsible for up to 96,000 deaths in the U.S. each year.
Omega-6s are prevalent in Western diets, however too much of these fats can cause various problems related to inflammation. The ideal ratio of omega-6 foods to omega-3 foods is about equal to, or at least at, a 2:1 ratio of omega-6s to omega-3s.
What are the risks of consuming too little omega-3s (plus too many omega-6s)? A lack of omega-3s can contribute to:
- Inflammation (sometimes severe)
- Higher risk for heart disease and high cholesterol
- Digestive disorders
- Allergies
- Arthritis
- Joint and muscle pain
- Mental disorders like depression
- Poor brain development
- Cognitive decline
Risks and Side Effects
The best thing about omega-3 foods and supplements is that omega-3 fatty acids don’t have any known drug interactions or adverse omega-3 side effects, according to some reliable sources.
Why might omega-3s be bad for you? The major precaution when introducing more omega-3s into your diet generally comes from the byproducts found in some seafood, such as mercury and other industrial chemicals.
When you purchase high-quality omega-3 supplements you won’t consume these contaminants, according to a number of tests that show the processing to create the supplements filters out the majority of concerning toxins.
As always, if you decide to start using a supplement to boost your intake, make sure you do so under the supervision of your physician/naturopath, who can monitor and advise you in the event you experience an adverse reaction.
Final Thoughts
- Omega-3s are a type of essential fatty acid your body needs for a great number of natural system functions.
- Most Americans do not consume enough omega-3 fats and/or have an improper ratio of omega-6s to omega-3s.
- The three main types of omega-3s are APA, EPA and DHA.
- Benefits of omega-3s include those related to heart health, mental illness or brain decline, inflammation, autoimmune diseases, and cancer.
- The best way to get enough is by eating foods rich in the nutrient, especially oily fish likes salmon, sardines, mackerel and tuna. Plant-based foods high in omega-3 fatty acids contain ALA, so you’ll need to eat more of them to get the same effect as their animal-based counterparts.
- You may also benefit from taking a high-quality omega-3 supplement. Aim to get between 250 and 500 milligrams of EPA and DHA combined each day.