While it might sound like a joke is coming — What blueberries and omega-3 fats have in common — it’s instead some really good news: Both of them have the potential to boost your brain power, but in different ways. A randomized, placebo-controlled, double-blind study, which lasted a total of 24 weeks and was recently published in Neurobiology of Aging,¹ noted that, yes, your brain measurably benefits from the anthocyanins in blueberries and the fatty acids in certain fish.

The fact that the two compounds together didn’t shoot off the charts in the brain-boosting category during the course of the study certainly doesn’t negate the positive effects of these two nutritional powerhouses; the omega-3 fats and blueberries used by the individuals in the clinical trial were recognized this way by the study authors:

“Enhancement of perceived functional capability suggests that fish oil-treated and blueberry-treated participants experienced meaningful improvement of cognitive capability, a notable finding, given that subjective cognitive complaints were an inclusion criterion for study participation.”²

So even though combining omega-3 fats and blueberries didn’t produce what scientists expected to be an exponential increase in cognitive performance in the 76 study subjects, what was already known in terms of the compounds they took in was just as dramatic and health beneficial as ever.

As a side, the study involved people from the Cincinnati area, who ranged in age from 62 to 80 and suffered from “mild, self-perceived” cognitive decline. The study did not include people who’d been diagnosed with Alzheimer’s or other cognitive problems, and none were already taking supplements or medications for dementia.

What Kind of Omega-3 Fats and What Kind of Blueberries?

Participants were placed in one of four groups: 19 in the blueberry group; 17 in the fish oil group; 20 were given both fish oil and blueberries and another 20 were given a placebo. Freeze-dried blueberry powder from sources in Maine and California was used for the anthocyanin testing. The omega-3 was administered in the form of fish oil capsules from the Inflammation Research Foundation³ in Massachusetts.

Nutra Ingredients⁴ notes that the fish oil capsules used in the trial contained 400 milligrams (mg) of EPA (eicosapentaenoic acid) and 200 mg of DHA (docosahexaenoic acid). The participants were directed to take two capsules with breakfast and two with dinner. The results were “surprising,” the researchers noted, as they found:

“ … [T]he EPA and DHA composition increased in the fish oil groups, while total urinary anthocyanin metabolites did not differ between the groups. However, they did find that urinary levels of glycoside and native food forms increased only in the blueberry-supplemented groups.

From the cognitive test results, the researchers learned that two groups — fish oil with blueberry placebo group and the blueberry with fish oil placebo group — each reported fewer cognitive symptoms. The blueberry group showed improved memory discrimination, leading the researchers to conclude that ‘supplementation improved cognition.’”

In case anyone ever wonders what scientists use as a placebo in such trials, the fish oil placebo was filled with corn oil. The blueberry was a “proprietary mixture” put together by the California source to appear and taste as close as possible to the blueberry powder, but with a different nutritional profile; without fiber, for example.

During the trial period, the subjects were instructed to take a dose of powder equivalent to one cup of blueberries per day, which previous studies indicated produced the optimal cognitive benefits, and to both limit and document when they ate other seafood and anthocyanin-rich fruit.

The “surprise,” again, was that the combination of already-proven compounds wasn’t associated with significant improvements, raising questions of why the “double whammy” of benefits was not forthcoming. The scientists could only conclude that it was unclear why they weren’t. Still, what was already known — and what is still readily available via animal-based omega-3 fats and dark-colored fruits like those already mentioned — is worth getting into.

Omega-3 Fat: How It’s Beneficial for Your Brain

Omega-3 fats are vital to your brain, helping to fight inflammation and offering numerous protections to your brain cells. For instance, a study in the journal Neurology found “older women with the highest levels of omega-3 fats … had better preservation of their brain as they aged than those with the lowest levels, which might mean they would maintain better brain function for an extra year or two.”⁵

In separate research, when boys were given an omega-3 supplement, there were significant increases in the activation of the dorsolateral prefrontal cortex part of the brain.⁶

This is an area of your brain associated with working memory. They also noticed changes in other parts of the brain, including the occipital cortex (the visual processing center) and the cerebellar cortex (which plays a role in motor control). In addition, older adults with memory complaints who consumed the DHA, alone or in combination with EPA, had improved memory.⁷

During pregnancy, omega-3 fats take on even more importance. A mother’s dietary intake and plasma concentrations of DHA directly influence the DHA status of the developing fetus, which can impact your child’s brain development. After delivery and while breastfeeding, omega-3 fats continue to be important, both for baby and for mom. In women, low levels of omega-3 are linked to an increased risk of postpartum depression.⁸ In children, supplementation early in life increases intelligence.⁹