The supplement industry wants you to buy their products, and they’re not above using a little parental guilt to make you into a customer. In the photo above, the promoter is my local pharmacy, where the large window display caught my eye:

Give your Child The Tools to SUCCEED in School!

Who doesn’t want their child to succeed? And if you knew a supplement could give you or your child a learning edge, would you consider it? I’d imagine many do. Supplements have a remarkable health halo. As a pharmacist myself, I’ve noticed this when speaking with patients – few consumers identify any potential risk or downsides to supplement use. Some don’t even think of them as medicine at all. The marketing has resonated: Supplements are perceived as “safe”, “natural” and “effective”. But whether you’re giving your child a prescription medicine to treat attention deficit hyperactivity disorder, or you’re giving a supplement to “improve focus and brain function”, you’re still administering a chemical substance to a child with the intent of changing brain function. We’d probably think twice before pouring an unknown substance in our car’s gas tank, especially one claimed to boost performance. We’d probably ask for some evidence that it works, and some assurance it wouldn’t harm our vehicle. A decision to use a drug or supplement in a child deserves just as much consideration of benefits and risks.

Kids DHA

The product on the left is advertised for use in primary and secondary school children. It’s called “Kids DHA”, and is marketed by Renew Life, a company which seems to think we are all contaminated with heavy metal toxins, and believes even migraines are caused by toxins. Kids DHA is claimed to “improve focus and brain function” and “promotes healthy eye and bone development.” The website’s claims are even more elaborate, including promises of “softer and healthier skin” and the ubiquitous “boost” to the immune system that every supplement seems to promise. Amazingly, they even make therapeutic claims about serious childhood illnesses, including “helpful for mental health, including childhood depression”.

Each capsule of KIDS DHA contains vitamin D and omega-3-fatty acids (docosahexaenoic acid (DHA) 100mg & eicosapentaenoic acid (EPA) 25mg), with a recommendation to give two doses per day. So what do we know about DHA and EPA? They are omega-3 fatty acids, which cannot be synthesized by the body. When eaten, DHA and EPA are incorporated into cell membranes, particularly the heart and brain. This is particularly important in pregnancy, so guidelines recommend pregnant women consume foods containing omega-3 fatty acids. In adults, there’s good evidence that fish oils (good sources of omega 3) have cardiovascular benefits. All the dietary guidelines I could find seem to be near unanimous in recommending that children and adults get sufficient omega-3 containing foods in our diet. It’s also a major component of the Mediterranean Diet, which has one of the better track records for cardiovascular and general health benefits.

Do DHA and EPA, when given as a supplement, improve focus and brain function, or promote eye and bone development? There’s no published evidence to demonstrate that this product has any meaningful effects. Nor is there any good evidence to show that DHA and EPA can improve focus in otherwise-normal children. If it had an effect, we might expect it to be most beneficial in children who couldn’t focus, or who suffered from learning disabilities. And that’s where it’s actually been studied. A Cochrane review of polyunsaturated fatty acids (PUFA) (which include omega-3 fatty acids like DHA and EPA) for attention deficit hyperactivity disorder (ADHD) in children and adolescents found 13 high-quality trials, and concluded there is little evidence that PUFA supplementation provides any benefit. Another Cochrane review looked at PUFA for children with learning disorders, and could not find any high-quality studies that have adequately examined its effectiveness.

With respect to the depression claim, the hard evidence is also lacking. There’s only a small study with methodologic issues (no intention-to-treat analysis). In adults, however, the evidence is promising, albeit based on limited data. Certainly there’s nothing persuasive to substantiate the claims made about the supplement being “helpful” for depression in children at all.

Are DHA and EPA harmful? There’s no evidence to suggest it’s harmful when consumed in the diet. In terms of guidelines, there are recommendations from the Canadian Pediatric Society to ensure adequate DHA and EPA, and consider supplements, in vegan children. The American Academy of Pediatrics recommends eating fish, and does not mention supplements. The Institute of Medicine doesn’t recommend a dose, citing a lack of evidence. However, most guidelines and advocates for omega-3 supplementation tend to recommend dietary supplements in those that don’t already have sufficient amounts in their diets. There’s also no evidence to suggest that taking DHA and EPA is inherently risky or harmful. So as a supplement for children, there’s not likely to be any observable beneficial effects, but we also don’t expect any harms.


The second product advertised is called Cerebrum, also from RenewLife, and the advertising makes a very specific claim on the poster:

  • Boosts cognitive ability by 10% for 6 hours after use.
  • Improves memory and focus.

The advertising on the website is even more specific:

Imagine for a moment being able to increase your cognitive ability and the positive impact that would have on your life. With Cerebrum™ you can! Cerebrum™ will increase your cognitive performance by 10% for a 6 hour period after taking it. Cerebrum™ contains Cereboost, a specific and unique extract of American Ginseng that has been clinically proven to increase cognitive performance by 10%!

Cerebrum is another fish oil supplement, but with American ginseng added. Each capsule contains 540mg of DHA, 27mg of EPA, 200mg of American ginseng (Panax quinquefolius), 5mg of lipase and 0.18 mg of rosemary extract. Here’s their “evidence” cited by the manufacturer:

Cerebrum evidence

click to embiggen

The data appear to come from a trial that evaluated ginseng alone: “Effects of American ginseng (Panax quinquefolius) on neurocognitive function: an acute, randomised, double-blind, placebo-controlled, crossover study.” The full study is online and frankly, the findings are not impressive. To the researchers’ credit, it’s randomized, double-blinded and placebo controlled. But the design and methodology are heavily biased towards finding positive results. The study looked at 3 different single doses of ginseng versus placebo, and participants went through a large battery of tests after 1, 3, and 6 hours after doses of 100mg, 200mg, or 400mg, with one-week periods between tests. The researchers found improvements in three measures, but not the rest. And even the positive effects are inconsistent. There was a statistically significant and consistent change in “choice reaction time” for the 100mg strength only. “Working memory speed” only improved consistently and significantly with the 200mg dose, but not the 100mg or the 400mg dose. “Alphabetic working memory speed” only improved with the 100mg and 400mg doses, and not the 200mg dose. Only “Corsi block performance” significantly improved across all doses and all durations. There were no consistent positive findings in all of the other tests. While the authors tout this as evidence of cognition and mood enhancement, the evidence is much less clear. There is no obvious relationship between dose and response, something we should expect if the ginseng is having a beneficial effect. It’s quite possible this is just random noise we’re seeing in the testing, and not a true effect. That conclusion is even more likely given the authors did not control for multiple comparisons. It’s exactly like the classic XKCD comic: test enough times, you’re bound to get something statistically significant. But statistically significant doesn’t mean it’s a real and meaningful effect. And that’s what we can conclude from the evidence for Cerebrum, and more generally, the evidence base for American ginseng. There’s a lack of evidence it has any meaningful effects.


The idea of a “natural” product that boosts cognition and learning, without downsides, is appealing to students and to parents alike. Despite the marketing, there’s no good evidence to suggest that either Kids DHA or Cerebrum will have any meaningful effects on learning or cognition. This is yet another example of spinning weak data to make it look like convincing. We’ve seen this movie before. We all want quick fixes, and reaching for a bottle in the pharmacy is about as quick and easy as you can get. But when it comes to learning, there’s no evidence that supplements need to play a role. Eat a decent diet, and feed one to your child. The “Tools to Succeed” that you or your child need won’t be found in the supplement aisle of your local pharmacy.




Posted by Scott Gavura