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'The Better Brain' Book Review

Two psychologists have studied nutrients and mental illness. Does it hold up?

Key points

  • Studies of supplements and mental health have almost universally disappointed.
  • Carefully formulated multi-nutrients in the right population may be beneficial, and there is plenty of reason to do more studies.
  • Data on multi-nutrients suggests they may help a subset of patients with various mental health conditions with few side effects.

The Better Brain: Overcome Anxiety, Combat Depression, and Reduce ADHD and Stress with Nutrition is a long-awaited compilation of decades of work by two psychologists, Drs. Bonnie Kaplan and Julia Rucklidge, who have more experience treating various forms of mental illness with supplements than pretty much anyone else. Unlike the typical self-help book authors who tee up some questionable interpretations of a few poorly done studies and a huge helping of individual anecdotes, Kaplan and Rucklidge have spent decades conducting independent* randomized controlled trials of broad-spectrum multi-nutrients and publishing their results.

The first chapter is the least interesting for any behavioral health professional—it discusses the major limitations of our current treatment paradigms for mental health. But we already know mental illness is a crisis and we don’t have the resources or the number of professionals needed to do appropriate treatment for all who need it, and unless there is some sort of magic fairy who will create bunches of social workers, psychologists, and psychiatrists, we aren’t going to be able to meet the demand any time soon. And, in truth, without other major resources like mental health facilities, housing supports, and other social services, a therapist or med on its own can only do so much.

Knowing the crushing burden of this problem and having a couple of psychologists come in saying “diet and supplements could help” might then seem ridiculous, outrageous even. However, the rest of the book is an elegant discussion of the research, limitations, and future prospects. Single-nutrient studies, with few exceptions, have almost always been a bust for almost any condition other than frank nutritional deficiency. Single nutrients make for simple variables and easy studies, so we’ve wasted a lot of time and money on them. This is why when you talk to a scientist or doctor about a supplement you will get some cranky replies like “expensive urine” or “there’s no evidence for supplements.”

But vitamins and minerals and omega-3s and amino acids in the diet all work synergistically. You need copper and zinc in the right combinations, and folate and B12 and zinc to work together to make neurotransmitters, and magnesium to (among other things) regulate the stress response system. The general theory is people undergoing a lot of stress or families with minor genetic metabolism deficiencies in some vitamin or energy metabolism sequence might need more than the vitamins and minerals you can get from a standard diet. Between the RDA (recommended daily allowance, determined as the amount most people need to prevent deficiency) and the UL (upper limit, the amount of a vitamin or mineral that can cause toxicity) is a range of dosing nutrients that should be safe for trials in various conditions, and that’s what Kaplan and Rucklidge have done.

For ADHD, several trials have shown that while broad spectrum multi-nutrients make no difference for some, a subset of children seem to respond quite well, especially in realms of irritability, aggression, mood, and sleep. The change does not happen overnight, usually over a few months, but in monitoring these children from an average of three and up to 12 years, the children tolerated the supplements without major side effects or problems. Other case studies have shown improvement in mood and aggression in various different mental illnesses, from bipolar disorder to a family with schizophrenia to behavioral dysregulation in autistic spectrum disorders to work with prison populations. The book is clear that all these latter conditions have not had randomized controlled trials or are undergoing trials, so there is no definitive answer on multi-nutrients yet.

Another fascinating use of the multi-nutrients has been in disasters. After the Christchurch, NZ earthquake, Rucklidge got permission to contact her study participants who were on placebos and multi-nutrients to see how they were doing with the acute stress of many losing homes and workplaces and friends and family. Kaplan studied multi-nutrients vs. a vitamin D control after a flood ravaged parts of Alberta. Rucklidge arranged for multi-nutrient supplements for volunteers among survivors of the Christchurch mosque mass shooting in 2019. In each case, a scale of stress measurement before and after four to six weeks of multi-nutrients showed a significant drop (by about 50%) in those receiving the micronutrients compared to a 10-15% drop in the untreated, placebo, or active control (vitamin D) groups. There is a lot of suggestive data that people under acute stress need more zinc and magnesium and their vitamin cofactors, and people after an acute disaster, displaced from their homes or traumatized, are more likely to be subsisting on convenience foods rather than focusing on nutrition. Here’s where you can start to make the connection between having plenty of nutrients available at the right times to increase natural resilience, and needing less advanced mental health support in the population at large.

The book has plenty to offer for people with no interest in supplements, with efficient and evidenced-based discussions of diet and mental health. Not only are there recipes and simple and inexpensive suggestions for increasing healthy and diverse nutrients in the diet, but also real-talk takes on gluten-free/casein-free and ketogenic diets (TL:DR; some people thrive but watch out for junk and not enough evidence to recommend for psychiatric conditions).

In short, The Better Brain is a valuable addition, and if you are short on time, skip to the second chapter, where the authors lose the standard “self-help” pep talk and start to get real and excited about their essential work.

*Kaplan and Rucklidge note they do not receive any grants or funding from the supplement companies except for free supplements and placebos for use in their clinical trials.

Copyright Emily Deans, M.D.

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