Dr. Walt Larimore has written a very mixed bag of a book, combining useful general advice about supplements and “natural medicine” with some questionable specifics about individual products.
Walt Larimore, MD, is a family physician, a medical journalist, a best-selling author, and a Christian evangelist whose organization Focus on the Family has as a goal, “To cooperate with the Holy Spirit in sharing the Gospel of Jesus Christ with as many people as possible by nurturing and defending the God-ordained institution of the family and promoting biblical truths worldwide”.
He sent me a copy of his new book The Natural Medicine Handbook: The Truth about the Most Effective Herbs, Vitamins, and Supplements for Common Ailments. I don’t share his religious beliefs, but I tried to tune out any mentions of religion and judge the information in the book solely on its scientific merits.
It is a useful handbook but is really a somewhat disconcerting combination of two books in one. The first 66 pages explain in detail why it is not a good idea to take supplements; the rest of the book recommends supplements to take for various health conditions, and even names the best brands.
In the Foreword, Dónal O’Mathúna says:
You should look in here before you grab your next natural remedy. You may not like everything you read because it might not confirm what you thought, heard, or hoped was the case. But you will find reliable, independent evidence that will help inform your health-related decisions.
Larimore says he relies on the recommendations or reports of multiple independent testing labs and trustworthy sources, but he appears to rely mainly on these two sources: ConsumerLab.com and Natural Medicines, formerly known as the Natural Medicines Comprehensive Database.
ConsumerLab tests products for identity, strength, purity, and disintegration. It publishes its test results on a subscription website and lists prices and “top picks”. Larimore provides their test results as a public service so his readers don’t have to subscribe. This is very convenient, but only goes so far. ConsumerLab can inform us about whether the content matches the label, but it can’t comment on how effective it is. It reveals that
- 46% of products tested contained less active ingredient than stated
- Some tablets don’t break apart properly and are less likely to be absorbed
- Deceptive labels list ingredients that are not in the product
- Some products contain dangerous ingredients like heavy metals or carcinogens
- Some products contain illegally added prescription, experimental, or unapproved drugs
- 51% of manufacturers failed inspections and received letters of noncompliance
- DNA testing of herbal supplements showed either contamination with other plant material or none of the content claimed on the label
Thanks to the Dietary Supplement Health and Education Act of 1994 (DSHEA), supplement manufacturers are not required to prove effectiveness, safety, or quality before marketing a product, and are not required to report discovery of adverse effects to the FDA.
Natural Medicines has long been my go-to reference for scientific information about supplements. It is a subscription database that rates natural medicines for safety and effectiveness. It assigns these ratings:
Safety: “likely safe”, “possibly safe”, “possibly unsafe”, “likely unsafe”, “unsafe”, and “insufficient evidence for safety”.
Effectiveness: “effective”, “likely effective” “possibly effective”, “possibly ineffective”, “likely ineffective”, “ineffective”, and “insufficient evidence for effectiveness”.
Larimore evaluated 1,300 natural medicines and interventions for 550 conditions/indications. He recommends 83 as effective and likely safe, to be considered in almost all cases, 67 as likely effective and likely safe, which he recommends in many to most cases, 88 as effective and possibly safe, which he recommends in some cases, 69 as likely effective and possibly safe or possibly effective and possibly safe, which he recommends in a few cases, 103 as possibly effective and possibly safe, which he recommends in a few cases. He recommends against using a whopping 888 products (insufficient evidence, possibly ineffective, possibly unsafe, ineffective, or unsafe). He claims to only recommend products that are both safe and effective, but his actual recommendations belie that claim. They include products that are only possibly effective and possibly safe. Is that good enough? Should the FDA approve marketing a prescription drug that is only possibly effective and possibly safe?
Reasons for use
The main reasons people use supplements is for overall wellness, energy, and to fill nutrient gaps. According to ConsumerLab, the most popular natural medicines are vitamin D (66%), magnesium (53.5%), followed by fish oil, CoQ10, multivitamins, probiotics, curcumin, and vitamins C and B. The majority of Americans have confidence in the safety, quality, and effectiveness of dietary supplements. That confidence is misplaced.
Calls to Poison Control Centers and ER visits for adverse effects of supplements are increasing. As Larimore reminds us,
If a substance has no side effects, then you can be 100% sure it has noeffects.
Healthy lifestyle habits are more effective than any natural medicine
He doesn’t recommend any natural medicines for wellness. Instead, he recommends these measures as both safe and effective:
- Avoid tobacco products
- Nutrient dense foods (fruits, vegetables, lean protein, heart-healthy fats)
- Regular exercise
- Restful sleep
- Weight control
- Limited or no alcohol
Other things he recommends as “likely effective” include fiber, mental stimulation, friendships, and prayer.
He quotes researchers writing in the Annals of Internal Medicine (emphasis added):
…most supplements do not prevent chronic disease or death, their use is not justified, and they should be avoided.
Unless a physician prescribes a specific supplement for a specific indication, dietary deficiencies are better remedied by changes in diet, not by taking pills.
Part 2: individual natural medicines
In the first part of the book, he recommends against multivitamins, dietary supplements, and herbal products. But in the second part of the book, he proceeds to recommend many of them; he covers the evidence for supplements intended to address common health problems and makes specific recommendations for treatment. In two chapters, he covers brain health and names names. He says there is insufficient evidence for nootropics and brain supplements such as coconut oil, gingko, ginseng, POM Wonderful, fish oil, resveratrol, turmeric, Neuriva, Prevagen, and many more. Several of these products have been covered on Science-Based Medicine.
In a chapter on cholesterol, he says “by far the most effective, safe, and economical treatment for abnormal lipids is a class of prescription drugs called statins”. His recommendations are confusing: he rates fish oil as effective and likely safe for hypertriglyceridemia, but then lists it under “insufficient evidence”.
Other chapters address energy drinks and caffeine; probiotics and digestive enzymes; celiac disease, irritable bowel syndrome, and inflammatory bowel disease; diarrhea, constipation, and indigestion; healthy hair and hair loss; heart health, hypertension, and heart attack; immune health (he lists routine vaccinations as effective and likely safe); skin and nail products (tanning booths, sunscreens, cosmeceuticals, and more); and dozens of weight loss remedies.
Conclusion: A useful compendium, but biased
Larimore provides an invaluable summary of evidence from Natural Medicines and ConsumerLab that would not otherwise be accessible without a subscription. I applaud that.
He provides a lot of valid science-based information, and I agree with much of what he says.
But I am torn when it comes to his recommendations. He promises to only recommend products that are both safe and effective, but then he recommends products that have not been proven safe and effective. They are supported by some evidence, but not the kind of high-quality evidence that most rigorously science-based observers would like to see.
Prescription drugs have had to demonstrate evidence of safety and effectiveness to the FDA before marketing. Supplements don’t have to do that. Prescription drugs must meet high manufacturing standards and are required to report adverse effects. In practice, supplements are not required to meet similar standards. Larimore has done an excellent job of pointing out all the reasons why we can’t trust supplements, but he seems to disregard those reasons in many cases, and it’s not clear to me why he makes the recommendations he does. In my opinion, he is biased in favor of natural medicines and supplements. And indeed, he takes an “integrative” approach that I distrust for the reasons David Gorski has explained. Remember Mark Crislip’s words about integrating cow pie with apple pie.
This article was originally published in the Science-Based Medicine Blog.