Omega-3 Fatty Acids: What They Do, Benefits & Supplements

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Omega-3 fatty acids, or omega-3s, are essential to overall wellness, especially if you’re at high risk for heart disease or already dealing with cardiovascular concerns. As your body can’t make them on its own, it’s up to you to ensure you consume healthy amounts of omega-3s through foods like fatty fish, nuts, and seed oils.

When that’s a challenge, supplements can be a convenient alternative to food sources of omega-3s.

What Are Omega-3 Fatty Acids?

Omega-3 fatty acids, or omega 3s, are essential fats that support a variety of important functions in the body, including overall heart health and mental health

The 3 primary types of omega 3s are:

  • Eicosapentaenoic acid (EPA): This type is found in fish and linked to anti-inflammatory effects. 
  • Docosahexaenoic acid (DHA): This type is also found in fish and connected to eye and brain health. It supports infant development during pregnancy, too.
  • Alpha-linolenic acid (ALA): This type is found in plants and is the most common omega-3 found in American diets. Small amounts can be converted to EPA and, to a lesser extent, DHA. It’s a known antioxidant, meaning ALA protects cells from oxidative damage.

Function in the Body

Omega-3 fatty acids play an important role in reducing inflammation, a key factor in heart, joint, and immune system health. They support healthy cell membranes, which your body needs for healthy skin, hair, and nails. Specifically, omega-3s help your blood vessels to dilate (expand).

They may provide neuroprotective effects in adults at risk for mental health or cognitive conditions. Healthy levels of omega-3s in pregnant women are linked to improved brain development and function in infants.

Polyunsaturated & Monounsaturated Fats

Omega-3s are unsaturated fats, which are considered essential fats for overall wellness. 

There are two types of unsaturated fats: polyunsaturated and monounsaturated. Omega-3s and omega-6 fatty acids are both polyunsaturated fats. The “poly” in the name refers to its chemical structure. (Polyunsaturated fats have multiple double bonds in their carbon chains.)

Monounsaturated fats are found in olive oil, avocados, and nuts. Much like omega-3s, they’re linked to heart health and balanced cholesterol. The “mono” in the name means they have a single double bond, but both types of fats are an essential part of a healthy diet.


The health benefits of omega-3s touch almost every body system, with a particularly powerful effect for those at risk of coronary heart disease.  

1. Heart Health

Omega-3s support heart health by reducing triglyceride levels. High triglycerides contribute to the hardening and narrowing of coronary arteries and blood vessels, leading to an increased risk of heart disease and poor circulation.

Some studies show a slight improvement in levels of high-density lipoprotein (HDL) cholesterol with a boost in omega-3s. That said, fish oil supplements shouldn’t replace a healthy diet if low-density lipoprotein (LDL) cholesterol is a concern.

Omega-3s may also lower your blood pressure and help regulate blood clotting. These positives, on top of their anti-inflammatory effects, contribute to a lower risk of cardiovascular disease, heart attack, and stroke, especially in adults already at risk of those conditions. 

2. Brain Function

DHA makes up 10-20% of the brain’s fat content. DHA is essential to healthy adult brain function and infant brain development. Deficiencies in DHA have been linked to more rapid cognitive decline in older adults. Healthy levels of DHA may provide some protective effects against Alzheimer’s disease.

2. Mental Health

Studies suggest a link between high levels of omega-3s and better mental health outcomes, including improved symptoms of depression and anxiety. More research is needed in this area, but the link could be another perk of the anti-inflammatory effects of omega-3s. 

3. Eye Health

DHA is essential to retina development in babies and continues to support visual acuity and eye health as we age. Healthy levels of DHA may protect against retinopathy, especially in adults with type 2 diabetes, and age-related macular degeneration. 

4. Skin and Hair Health

Omega-3s support moisture retention and skin barrier function, which can have a positive effect on dry skin, including on the scalp, acne breakouts, and skin irritation. Controlled trials show they may also provide sun protection and act as a barrier against skin diseases

5. Anti-Inflammatory Properties

Inflammation is the main culprit behind many chronic conditions. When it attacks the joints, it can cause stiffness, pain, and rheumatoid arthritis. Studies show getting enough omega-3s may reduce arthritis symptoms like swelling and joint tenderness. 

Limited clinical trials show that the anti-inflammatory properties of omega-3s may also have cancer-fighting effects in patients with breast cancer

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Omega-3 Foods

Fatty or oily fish are the best sources for higher levels of DHA and EPA. Types of fish high in omega-3s include:

  • Mackerel
  • Salmon (wild or farmed, Atlantic)
  • Herring
  • Anchovies
  • Sardines
  • Whitefish
  • Tuna
  • Cod liver oil

If you can’t eat seafood or don’t like eating fish, you can get a dose of essential fatty acids from certain plant sources. Plant-based omega-3 sources include:

  • Flaxseed and flaxseed oil
  • Soybeans and soybean oil
  • Canola oil
  • Chia seeds
  • Walnuts
  • Edamame
  • Seaweed
  • Kidney beans
  • Hemp seeds

Are Omega-3 Supplements Good for You?

Omega-3 supplements can be good for many people, especially those with cardiovascular disease or high triglycerides. Pregnant women and vegans unable to consume fish proteins may benefit from supplements, too. 

Due to the amount of mercury in our oceans, and therefore our fish, we must be very careful about the types and quantity of fish we consume. And while it’s best to try to get healthy amounts of omega-3s from food sources like fatty fish, following a new diet may not be possible for everyone. 

Supplements can then offer positive health benefits like improved heart outcomes, brain function, and reduced inflammation in an easily accessible way, without the risk of mercury poisoning when using high quality, well-sourced brands.

Recommended Daily Intake

The American Heart Association (AHA) suggests bumping up your fish consumption to at least two times per week. A serving size is about 3 oz of fatty fish, about the size of the palm of your hand.

The National Institutes of Health (NIH) Office of Dietary Supplements defines healthy omega-3 consumption as about 1-1.6 grams of omega-3s per day. A regular serving of fish is then more than enough to meet that recommendation as part of a daily diet.

There is no recommended daily intake for omega-3s in supplement form, but the U.S. Food and Drug Administration says up to 5,000 mg per day is safe for most healthy adults.

Omega-6 to Omega-3 Ratio

Omega-6s are another type of unsaturated fatty acid essential for your body to thrive. Whereas omega-3s help your blood vessels expand, omega-6s help your blood vessels contract, or get smaller.

Our ancestors generally got a 1:1 ratio of omega-6s to omega-3s in their diet (for context, I advise patients to get as close to 1:1 or even 1:3 as possible).

Sadly, the Industrial Revolution and how it impacted farming means most Westerners get closer to a 15:1 ratio. Foods with previously balanced levels of 6s to 3s now have more omega-6s due to factory farming. Quick, ‘easy,’ pre-packaged foods containing fats are almost always high in omega-6s with little to no omega-3 content.

The risk of chronic diseases (heart disease, non-alcoholic fatty liver disease, IBD, Alzheimer’s, obesity, and rheumatoid arthritis) increases as this ratio becomes more unbalanced

We check omega-3 levels for almost every one of our patients. The vast majority of the time, people are deficient in omega-3s and have an excess of omega-6s if they’re not consuming fish daily or taking a fish oil supplement.


Is fish oil the same thing as an omega-3 supplement?

Fish oil is not the same as an omega-3 supplement, but it’s the most popular source of omega-3 in supplement form. Not all omega-3 supplements are derived from fish oil; some are plant-based. Fish oil is the most bioavailable form of consuming omega-3 fatty acids.

How can vegans or people on plant-based diets get more omega-3s?

Vegans or vegetarians can get more omega-3s by consuming foods like chia seeds, flaxseed, and walnuts. They can also take plant-based supplements that contain algal oil over fish oil (look for omega-3 supplements containing only ALA).

Who should not take omega-3 fatty acids?

People allergic to fish should not take marine-derived omega-3 fatty acids. Pregnant or breastfeeding women should avoid fish like swordfish with high levels of mercury and other possible contaminants.

Due to a decrease in platelet aggregating (clotting)with high doses of omega-3s, those on blood-thinning medications should speak to their healthcare provider before taking supplements. 

However, although there is a decrease in platelet aggregation, this study showed that there was no actual increase in bleeding during or after surgery and questions the common recommendation of stopping omega-3 supplementation prior to surgery.

There may also be a connection between high doses of omega-3s and cardiac arrhythmias in some. Staying at doses lower than 4,000mg in people with a risk for arrhythmia is considered safe.

Should I take omega-3 fatty acids every day?

You should take omega-3 fatty acids every day if you have or are at risk for conditions that would benefit from a higher dose of omega-3s, including heart disease and some mental health conditions. We advise all pregnant women or women who are trying to concieve to consume high doses of omega-3’s every day to support fetal brain development.

What are the side effects of taking omega-3 supplements?

Possible side effects of taking omega-3 supplements include a fishy aftertaste, indigestion or digestive discomfort, and an increased risk of bleeding gums and nosebleeds.

Get Your Omega-3s

If you’re worried that you’re not getting enough omega-3s from diet alone, supplements can help. Our supplement <product> supports brain, heart, and immune health with a formula made for optimal absorption.


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