What Are Omega-3s, Actually? Here's The Lowdown On These Healthy Fats
Even during the days of low-fat everything, one specific type of fat maintained its "good for you" status: omega-3s. And though nutrition science and health trends have since brought all sorts of dietary fats back into the mainstream's good graces, omega-3s still deserve some extra attention.
The bottom line is: you need your fair share of these high-profile fats in order to feel your best.*
Though they're most famous for heart health, omega-3s fuel a slurry of important processes in the body, supporting everything from your brain to your eyes.*
If that's the extent of your knowledge about omega-3s, don't sweat it; you've come to the right place.
Consider this your one-stop guide to all things omega-3s, from what they really are and what the difference between EPA and DHA is to why they're so important for your body and how to get more of them (because, nope, eating fish isn't your only option).
What are omega-3s?
Salmon, herring, anchovies, sardines, mackerel, and albacore tuna all land in the higher-fat fish category, delivering a great source of marine omega-3s EPA and DHA.
Harris goes on to say this about EPA and DHA: "These are fatty acids that our bodies are very inefficient at making and so are best supplied directly through the diet." (For this reason, they're known as "essential" [ALA] or "conditionally essential" [EPA and DHA] fatty acids by many renowned lipid researchers, including Harris.)
Types of omega-3s
Within this family of omega-3s, there are three specific fats you've probably heard of before—and that are praised far and wide for their various health benefits: EPA, DHA, and ALA.*
You can't really compare them apples to apples, though. "They are simply different chemical compounds with different biological actions," explains Harris. On a chemical level, ALA is 18 carbons long whereas EPA and DHA are 20 and 22 carbons long, respectively.
ALA (alpha-linolenic acid)
That said, ALA has its own benefits independent of its ability to transform into EPA and DHA. In addition to supporting the body's anti-inflammatory pathways and promoting brain health and mood, research has even recently linked ALA with longevity.*
EPA (eicosapentaenoic acid)
It contributes to the often-talked-about health benefits of omega-3s, including but not limited to supporting immune function, cardiovascular and joint health, and fetal development7.*
DHA (docosahexaenoic acid)
Similarly, DHA is also a long-chain PUFA found in algae and fish. This particular omega-3 is found in high concentrations in the retina and brain8 (i.e., the central nervous system), making it essential for the development of our brain and eyes, as well as vision and cognitive function throughout life.*
The health benefits of omega-3s
Omega-3s serve plenty of important purposes throughout the body (and the lifespan).* Though research continues to develop, there are a few specific health perks that have been well-established:
Eye health & vision
In fact, consuming EPA and DHA combined may reduce the risk of CHD (coronary heart disease) by helping to lower blood pressure.† One serving of omega-3 potency+ provides 1.5 grams of EPA and DHA, an amount ample enough to contribute to this cardiovascular role.
Mood & brain health
Pregnancy & fetal development
The best sources of omega-3s
Fish are our most obvious source of omega-3s and provide the body with the long-chain omega-3 fatty acids EPA and DHA.*
That doesn't mean that people who don't consume animal products are out of luck, though. Since sea plants like algae are the original source of omega-3s for fish, you can get EPA and DHA by consuming them as well.
Of course, many people turn to supplements in order to up their intake of omega-3s, whether from fish or plant sources. The most popular options out there: fish oils for omnivores and algae (algal oils) for strict vegans. For specific recommendations, check out our omega-3 supplement roundup.
How many omega-3s do we need?
Research has long shown that Americans don't consume much fish. "Typical intakes of EPA and DHA in the U.S. (a low fish-eating country) are about 100 to 150 milligrams per day, on average," Harris explains. "In countries like Japan or Korea, where fish is eaten nearly every day, though, intakes are between 750 and 1,000 milligrams per day."
As a result, "the typical American has an omega-3 index of 4 to 6%, whereas the typical Japanese and Korean person falls between 8 and 12%," he says. (A level equal to or greater than 8% is considered optimal.)*
Achieving an optimal omega-3 index, Harris says, would require most Americans to consume about 1,000 to 1,500 milligrams of EPA+DHA per day—a far cry from the average current intakes in this country.
Indeed, mbg's vice president of scientific affairs Ashley Jordan Ferira, Ph.D., RDN, shares that, "Nationally representative data proves how low our fish intake truly is, with more than 90% of Americans22 failing to consume the recommended (baseline starting point) two servings of fish per week, which equates to roughly 500 mg of EPA plus DHA daily. On average, as a country, we're actually eating less than 90 mg of these marine omega-3s23 per day."
She goes on to say, "Mind you, we actually need a 1,000 milligram-plus to optimize heart and whole-body health throughout life. That superior amount of omega-3s is the equivalent of eating a fish a day."*
Bottom line: Unless you plan on incorporating fish into your daily meal plan, a high-quality omega-3 supplement (that contains a potent, science-backed dose of EPA and DHA) is a must.*
A note about our omega-6 to omega-3 ratio...
Fun fact: Omega-3s aren't the only omegas out there. Omega-6 fats, which are found in many plant foods (most notably vegetable oils, with canola and soybean oils being some of the worst offenders), are another component to consider when evaluating your omega-3 intake.
Here's the deal: While omega-6s play a role in brain development and function (among other things), they also promote inflammatory pathways in the body.
This isn't a bad thing, as long as we maintain the proper balance of omega-6s and omega-3s. That's where things get a little hairy.
As Ferira puts it: "Striking a balance of these PUFAs is critical. Pro tip: You'll want to dial down the omega-6 fats, and dial up the omega-3s. Our nation's health would be greatly benefited if Americans tipped the fats equation in this way."*
What's at stake when we don't get enough omega-3s?
Given all of the good things omega-3s do throughout the body, it's no shock that falling short on them isn't exactly ideal for our health.
According to Harris, having too little omega-3 in your diet (and therefore in your blood and tissues, organs, systems, and whole-body) contributes to suboptimal cardioprotection, cognition, (musculoskeletal health, vision, etc.) and overall vitality.*
Feel a little more fluent in the language of omega-3s? These healthy fats are important for maintaining a number of areas of health, including everything from your cardiovascular system to your mood.*
And though ALA, EPA, and DHA all offer individual benefits, it's important to keep in mind that loading up on ALA is certainly not a replacement for getting your EPA and DHA in, too. In many cases, supplementing with a properly dosed fish oil is important for getting ample amounts of EPA and DHA into the cells and tissues in your body that need them on the daily.*
If you are pregnant, breastfeeding, or taking medications, consult with your doctor before starting a supplement routine. It is always optimal to consult with a health care provider when considering what supplements are right for you.
Josey Murray is a freelance writer focused on inclusive wellness, joyful movement, mental health, and the like. A graduate of Wellesley College, where she studied English and Creative Writing, her work appears in Women’s Health, Cook & Culture, and more. By expressing her own vulnerability, she writes with warmth and empathy to help readers find self-compassion and true wellness that’s sustainable for body, mind, and planet.