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I'm a Pharmacist and Warn Against These Supplements

Pharmacists warn to stay away from these five supplements. 
FACT CHECKED BY Emilia Paluszek

Millions of Americans take a daily supplement to help maintain the vital nutrients our body needs and improve overall health, but not all are as safe and effective as advertised. Some don't provide any benefits, while others can cause harmful side effects. Eat This, Not That! Health spoke with pharmacists who reveal which supplements to stay away from and why. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Vitamin A

weaker bones

Andy Boysan, Director and Superintendent Pharmacist at The Independent Pharmacy says, "Vitamin A supplements should be carefully monitored when taken by older people, especially the elderly. While the vitamin promotes good vision and a healthy immune system, it may raise the risk of osteoporosis, a bone-weakening condition. Of course, our bones naturally weaken as we age, but the condition can quickly exacerbate this process by making bones very fragile and prone to breaking. In a matter of years, pain, difficulty walking, and weakness can all lead to a loss of independence."



Calcium supplement tablet pills on dark wooden background

Dr. Boysan tells us, "Calcium is beneficial to bone health, tooth strength, and weight management, all of which are common concerns as we age. Calcium supplements, on the other hand, have a number of risks for those aged 50 and older, such as heart attacks, adding to the already increased risk that comes with aging."



young woman taking pill
Shutterstock / New Africa

Dr. Pana Ninan, PharmD, BS Functional Medicine Practitioner and Pharmacist tells us, "Multivitamins are taken to help supply our body with key minerals or vitamins we may be missing in our diet. The problem is the multivitamin is synthetic or artificial; created to mimic nature's vitamins and minerals. Synthetic vitamins may not be absorbed as well as nature's vitamins. Much of what we purchase gets excreted instead of absorbed. It is always best to get your vitamins through choosing a variety of real, whole foods." 


St. John's Wort

Fresh St. John's wort flowers in a bowl, top view

According to Dr. Boysan, "St John's Wort, taken as a tea or as a supplement, can help with symptoms of depression, lung problems, and kidney problems. However, when combined with some antidepressant medications, the results can be fatal if your serotonin levels become dangerously high. Before taking St John's Wort, older people who have been taking antidepressants for years should seek professional advice."



Sacred mature woman.

Brain health is vital to our overall well-being, but Dr. Ani Rostomyan, Doctor of Pharmacy, Holistic Pharmacist and Functional Medicine Practitioner warns prevagen isn't the way to go to improve memory. 

"Prevagen is a product marketed for memory improvement, which is a once daily supplement available as oral capsules or chewable tablets. Each version contains 50 mcg (2,000 units) of vitamin D3, (as D3 cholecalciferol) and varying amounts of Apoaequorin, a protein found in certain types of jellyfish. The three different strengths of Prevagen contain either 10 mg, 20 mg, or 40 mg of Apoaequorin.

A study by Kuzma et al. from 2017 found possible correlation between moderate or severe vitamin D deficiency and visual memory loss. The study authors noted this finding does not mean low vitamin D levels cause memory loss and called for further research in this area. Based on this and other similar studies, some OTC manufacturers promote taking vitamin D to prevent memory loss. However, there are no studies showing regular use of this supplement prevents memory loss.

Apoaequorin is a protein found in a type of jellyfish, which acts similar to a protein in our bodies called calmodulin, presumably playing a substantial role in memory improvement. When taken orally, most of the bioavailability is diminished due to interaction with stomach acid and liver enzymes and it's unknown what percentage actually reaches systemic circulation. The evidence on memory improvement is based on a small study, published in 2016, which lasted only 90 days, comparing 10 mg of apoaequorin per day to placebo. In my opinion as a Pharmacist, 90 days is not a valid time frame to assess memory improvement and the study didn't use validated standardized memory assessment questionnaires. The evidence behind the claims of improving memory is not consistent and valid, and the product is not FDA approved for memory loss." 

According to Harvard Health, "The US Federal Trade Commission wasn't convinced of the supplement's benefits. It charged the supplement maker with false advertising back in 2012. In the legal filings, the company was accused of selectively reporting data and misleading the public though claims that Prevagen is "clinically proven" to improve cognitive function. The lawsuit has not yet been decided."

Heather Newgen
Heather Newgen has two decades of experience reporting and writing about health, fitness, entertainment and travel. Heather currently freelances for several publications. Read more about Heather