Are you getting enough omega-3 fatty acids?

New study shows larger doses are key for brain health

A couple of years ago, after looking at many studies, it became apparent to me that research on omega-3 essential fatty acids and fish oil (which contains omega-3s), used woefully inadequate doses.

Studies that found no health benefits for omega-3s used pathetic, tiny, meaningless doses of 1,000 mg a day…or typically even less. But studies that used just marginally adequate doses of 1,000 to 2,000 mg a day showed benefits for heart health, brain health, and relief of chronic inflammation (which, of course, is a key factor for heart and brain health).

The pattern was clear.

Adequate doses support the health benefits of omega-3’s. (It’s ridiculous to expect to see benefits when sub-therapeutic doses are used anyway.)

So, after looking at reams of research and debunking claims from mainstream ninnies that omega-3s don’t work, I updated my own recommendations for the best doses of omega-3s.

But those dosages aren’t just a simple number that will work for everyone across the board. The key is taking into account how much fish and seafood you already eat, because fish oil and omega-3 supplements are supposed to be just that—supplemental to your diet.

For example, if you eat fish at every meal, you don’t need omega-3 supplements. And if you eat fish several times a week, your need for supplements is lower. But if you never eat fish or seafood (like all too many people), you need higher doses of omega-3s than recommended by mainstream minions or even most “natural know-it-alls.”

Although I’ve sorted all of this out (see the chart in the sidebar for my recommended doses based on how much fish you eat), I haven’t seen many other “experts” embracing the truth of this simple premise.

But I recently came across a new study that finally echoes what I’ve been saying all along. So, let’s take a look…

Omega-3s on the brain

Many prior studies have shown that omega-3s can reduce the risk of dementia. These studies typically used doses of 1,000 mg or less. But some studies using the same low doses failed to find benefits for curtailing cognitive decline.

Researchers at the University of Southern California addressed this discrepancy by directly comparing omega-3 levels in people’s blood with levels in their brains.1

This is important because prior studies were based on the simple assumption that oral doses of omega-3s make their way into the brain (meaning omega-3 levels in the blood also reflect the levels in the brain).

The researchers recruited 33 men and women who had risk factors for Alzheimer’s—a family history of the disease, lack of moderate exercise, and diets low in fish—but didn’t have cognitive impairment.

Participants were randomly assigned to take either 2 grams (2,000 mg) of an omega-3 supplement daily for six months, or a placebo. Both groups also took a daily vitamin B complex, which helps the body process omega-3s. (Of course, other studies show that B vitamins also protect the brain.)

At the beginning and end of the study, researchers measured levels of omega-3s in the participants’ blood and in the cerebrospinal fluid in their brains.

The researchers discovered that while the supplement group had omega-3 blood levels that were a whopping 200 percent higher compared to the placebo group, the amount of omega-3s in their brains was only 28 percent higher.

Fish oil lessons from our ancestors

The researchers concluded that when people take less than 2,000 mg of omega-3s per day, there’s less than a 10 percent increase in omega-3 brain levels—which isn’t a meaningful amount biologically or neurologically.

In other words, these findings show that higher doses of omega-3 supplements are needed to make a difference for brain health. That’s because even significant increases in omega-3 blood levels are only accompanied by small increases in the brain.

This makes sense when you consider that early humans first settled where there were abundant marine foods that could be gathered right along the shoreline. Some experts think that consuming all of this seafood and omega-3s supported the rapid increase in human brain size that’s associated with the rise of human society and complex civilizations.

But today, most humans don’t have these opportunities—or even the inclination—to eat that much fish. And for those people, the 2,000 mg of daily omega-3 supplements used in the study is even substantially lower than I recommend. (See the sidebar on the previous page.)

Still, it’s a good first step. The researchers are reportedly working on a larger, longer study on fish oil and brain health—so I’ll be sure to share those results in an upcoming newsletter, and in my Daily Dispatch. (And next month, if you celebrate Christmas, perhaps you’ll get to participate in the Feast of the 7 Fishes, as I’ll also describe in an upcoming Daily Dispatch.)

Just imagine what they can discover if they use better, higher dosages of omega-3s!

SIDEBAR: My recommended omega-3 supplement doses

Fatty fish and seafood—including wild-caught Pacific salmon, Atlantic mackerel, trout, shrimp, or sardines or anchovies in olive oil—is the best source of omega-3 essential fatty acids. But dietary supplements can fill in the gaps if you don’t eat fish every day. So, here’s what I recommend:

If you eat fish three to five times a week, then you only need to supplement with 1,000-3,000 mg of fish oil daily. Make sure you choose a product that contains 400-950 mg of EPA fatty acids and 300-700 mg of DHA fatty acids.

If you eat fish two to three times a week, I recommend 4,000-5,000 mg of fish oil every day, including 1,400-1,800 mg of EPA and 1,000-1,300 mg of DHA.

If you don’t eat any fish, you’ll probably need 6,000 mg of fish oil a day, with 2,000 mg of EPA and 1,500 mg of DHA.


1“Brain delivery of supplemental docosahexaenoic acid (DHA): A randomized placebo-controlled clinical trial.” EBioMedicine. 2020;102883.