WARNING!
This is an older article that may not reflect Dr. Mercola’s current view on this topic. Use our search engine to find Dr. Mercola’s latest position on any health topic.
By Dr. Mercola
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 1 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
Are You Getting Enough Omega-3s?
Having the optimal levels of DHA and EPA in your blood is a relative rarity, according to Bill Harris, president of OmegaQuant, who covered the topic in partnership with Aker BioMarine.10 Significant to note is that optimal levels of the omega-3 fatty acids EPA and DHA are fairly rare in people worldwide except in areas where fish is eaten often, such as Greenland and Japan. In the U.S., however, around 95 percent of the population is omega-3 deficient.
While it may not seem like a big deal to be deficient in omega-3s, especially if you're not aware of the implications, Harris explains it rather well: "Higher disease burden and shorter lifespans." Testing for omega-3 levels is becoming more common because the concern is growing, Harris maintains. It requires a drop of blood on specially treated paper, which is sent to a lab to determine the amount of EPA and DHA in test subjects' red blood cells.
Expressed as a percentage, the range considers 8 to 12 percent to be "optimal." If fish isn't on your menu very often, your omega-3 index is likely between 3 and 6 percent, which is low — too low. How can you raise your omega-3 index, you might ask?
It's a question of diet, one way or another, whether it's through the consumption of animal-based EPA and DHA supplements, or eating healthy amounts of seafood, particularly wild-caught Alaskan salmon, krill oil, sardines, anchovies and herring, all of which are plentiful in omega-3s.
Omega-3s: Good for Your Gut and Heart
Omega-3 polyunsaturated fatty acid (PUFA) supplements were researched in a U.K. study involving a number of university hospitals. The researchers concluded that omega-3 supplementation increases several short-chain fatty acid-producing bacteria.11
In fact, studies are clear that when you consume the optimal amount of omega-3s on a regular basis, you get a 230 percent return on your investment, according to one study. For every $1 spent on omega-3 supplements, health care costs related to heart disease were reduced by $2.30.12
As far as supplementation goes, Harris recommends taking 500 to 1000 mg of EPA and DHA — not just "fish oil" — per day, and to continue it for several months to move yourself into a more acceptable range for your best health. You may not "feel" bad, even if you discover your omega-3 is at a low level.
Uninformed entities in the medical community may say you need to "lower your cholesterol" to improve your heart disease risk, but, rather than the statins that are typically prescribed to remedy a "problem" of high cholesterol, a medication is not necessary or even good for low omega-3 levels in your blood. Your best bet is to eat good seafood or take a quality supplement, such as krill oil. Harris writes:
"The Omega-3 Index is a better predictor of risk for heart disease and even premature death than is cholesterol. This was the conclusion of a major study we recently published from the Framingham Heart Study …
We found that people (average age 66) with the highest Omega-3 Index levels were 35 percent less likely to die from any cause in the ensuing seven years than people with the lowest Omega-3 Index levels. But the same was not true of cholesterol — there was no difference in risk for death in people who had the lowest versus the highest cholesterol levels."13
Anthocyanins: Prevent Cognitive Decline and More
Anthocyanins are the color coordinators of the food world, because they not only give grapes, radishes, red cabbage and black raspberries their deep hues, they play a big part in improving a wide array of health conditions, most notably boosting your brain with free radical-fighting power and combating colds, colitis14 and even cancer.15
Not just blueberries but the anthocyanins in several deep-colored fruits have been shown to be extremely advantageous: cranberries to tackle urinary tract infections,16 aronia berries for inflammation17 and elderberries to lower high blood pressure.18 It's not so surprising, then, that these compounds are so great for your brain.
Pterostilbene: Another Antioxidant Compound in Blueberries
A 2013 study remarked on another uncommonly beneficial component found in blueberries: pterostilbene, a natural compound first isolated from red sandalwood (Pterocarpus santalinus) that increased the bioavailability of antioxidants to an impressive degree. In fact, the study notes:
"The antioxidant activity of pterostilbene has been implicated in anticarcinogenesis, modulation of neurological disease, anti-inflammation, attenuation of vascular disease, and amelioration of diabetes. Substantial evidence suggests that pterostilbene may have numerous preventive and therapeutic properties in a vast range of human diseases that include neurological, cardiovascular, metabolic, and hematologic disorders."19
In addition, pterostilbene was found to be a "potent anticancer agent in several malignancies," inhibiting cancer growth through altering cell cycles, apoptosis, inhibiting metastasis and, overall, unleashing the power of antioxidants in a number of cancer cell lines.20 A recent study, "Blueberry Extract Could Kill Bladder Cancer Cells," notes the apoptosis-generating (aka malignancy-killing) effects of pterostilbene on bladder cancer, including chemotherapy-resistant bladder cancer.21
Other research on cancer prevention observes that blueberries inhibits triple negative breast cancer tumors, described as aggressive and hard to treat, while inhibiting the initiation and progression of cancer growth, according to Wild Blueberries.22 Further, pterostilbene may also reduce blood fat levels.23
Life Extension24 calls pterostilbene the "other resveratrol," as it, too, is a plant extract that brings about many of the same effects as calorie restriction, and regulates genes implicated in such diseases as diabetes, cancer, atherosclerosis and, yes, age-related cognitive issues like Alzheimer's and other forms of dementia.
More About Pterostilbene
Pterostilbene and resveratrol are closely related stilbene compounds, but their functions differ; they work synergistically to activate the genes that literally and positively impact your longevity. In effect, pterostilbene has beneficial effects on gene expression, while enhancing those of resveratrol.
Most people think of genes as being fixed in terms of ability to change the messages your genes communicate to your body. The process is a matter of some type of stimuli, inside or outside, that "switches on" certain genes in a phenomenon called modulating gene expression. To clarify:
"Calorie restriction turns on genes directly related to long term survival. This includes genes that reduce the activity of certain cancer-promoting agents, genes that induce programmed death of cancer cells, and genes that confer neuroprotection. The incredible news is that many of the same genes that confer a longer life span can be favorably modulated with plant extracts such as resveratrol and pterostilbene."25
Evidence-Based Complementary and Alternative Medicine notes a study26 showing pterostilbene has a wide variety of health advantages besides those already mentioned; it:
- Shows lipid lowering and antiobesity effects
- Is as effective as diazepam (brand name Valium) as an anti-anxiety agent, without problematic side effects
- Is a natural compound that is as efficacious as synthetic clinically used drugs
- May help with weight loss
- May lower blood pressure; patients on a 250 mg-per-day dose "achieved significant reduction in blood pressure"
As a supplement, studies have shown that pterostilbene is generally safe for humans in dosages up to 250 mg/day.27