Supplements: Too Much Of A “Good” Thing?

I don’t want for us to take pills anymore, not that it’s bad. We’ll be stronger if we don’t need them.

AsianScientist (Oct. 4, 2015) – Walk into your local pharmacy and you are almost certain to find at least one entire shelf dedicated to health supplements. There, you will find a dazzling array of bottles in every shape and size; promising you a new shape, victory against the common cold, and—a claim that I take particular issue with as an immunologist—to “boost your immunity.”

Because they come in tablets, syrups and gel capsules that look comfortingly similar to the medicines prescribed by doctors, many people are surprised to find out that health supplements do not in fact need to be approved by the Food and Drug Administration. Here in Singapore, health supplements are not subjected to pre-market approval by the Health Sciences Authority, and can be imported and sold without a license.


But it’s natural!

While it may be true that humankind has been using herbs like St. John’s wort, echinacea and ginkgo for centuries with no apparent ill effects, it does not necessarily mean that whatever is ‘natural’ need not be regulated.

First of all, supplements may not even contain the herbs that are supposed to help you. In 2013, a DNA barcoding study revealed that one third of the supplements tested did not contain even a trace of the plant advertised on the bottle. In place of the ‘active ingredient’? Rice powder, laxatives and black walnuts which could have triggered life-threatening reactions in those with nut allergies.

But wait, there’s more. This year, the New York State attorney general reported an even more damning result: a whopping 79 percent of the herbal supplements they tested did not contain the any of the herbs listed on their labels.

Furthermore, the companies producing these supplements were no small fly-by-night operations but four of the biggest players—GNC, Target, Walgreens and Walmart. [Each company was issued a cease-and-desist letter, which you can read here.]

If you have somehow managed to buy one of the products in the 21 percent that actually contains the herb you’re looking for, don’t be too happy yet. Take good old St. John’s wort for example, which is used to treat mild depression. If you are on birth control pills or immune suppressants to prevent transplant rejection, you might want to avoid St. John’s wort because of the drug interactions it causes.

Ironically, people already on antidepressants such as Prozac, Zoloft and others should not take St. John’s wort as it “tends to increase side effects, and could potentially lead to a dangerous condition called serotonin syndrome.”


But it’s scientifically proven!

Ok, so maybe herbal supplements aren’t the best thing since sliced bread. But what about vitamins and minerals? Aren’t they scientifically proven to be absolutely essential for life?

Yes, of course, but unless you are a woman trying to have a baby or have a specific nutritional defect, you are probably already getting enough vitamins and essential minerals from your diet. [And if you are living on a diet of fast food, simply popping a few supplement pills does not address the underlying problem of poor nutrition anyway.]

That is not to say that vitamin deficiencies are not a problem. Here in Asia, where cultural barriers and lactose intolerance mean that dairy products are not typically part of the diet, calcium deficiency is a serious issue. A 2015 study published in Scientific Reports found that the mean calcium deficiency risk in Asia was 57 percent, underscoring how more work is needed to help Asians reach their recommended daily allowance (RDA).

But as with any drug or food, the dose makes the poison. In other words, just because a vitamin or mineral is essential doesn’t mean that consuming more than your daily allowance will make you extra healthy. Look again at the chart with the RDAs, do you notice the column titled “upper limit” just next to it? It’s there for a very good reason; too much calcium is bad for you.

A 2013 study published in JAMA Internal Medicine found that a daily intake of more than 1,000 mg supplemental calcium was associated with a 20 percent increased risk of death from cardiovascular disease. To add insult to injury, a recent meta-analysis published in the British Medical Journal has concluded that “evidence that calcium supplements prevent fractures is weak and inconsistent.”

Even when a high dose of vitamin or mineral doesn’t harm you, your body may simply not be able to absorb it all, and you are quite literally flushing the money you spend on supplements down the drain.

As an experiment, dissolve one of those vitamin B complex effervescent tablets in a glass of water and drink it. Wait a few hours and then sneak a look at your pee when you next head to the loo. Bright, neon yellow? Don’t worry, you haven’t been poisoned with radioactive waste; your body has just excreted all the riboflavin (vitamin B2) it couldn’t absorb.


No substitute

Thoroughly confused by all this detailed and seemingly conflicting information? Welcome to science! There are no unconditional truths; ‘facts’ like ‘calcium is good for you’ rest on assumptions that you are really getting calcium from the supplements you take and in the right dose.

If you are still seeking a clear cut take home message, it is simply this: eat well and try to get your nutrition from there. Instead of spending money on supplements, spend some time on cooking your own food, choosing a good mix of vegetables and proteins. Supplements, when properly researched, certainly can benefit, but there is no substitute for a healthy diet.


This article is from a monthly column called From The Editor’s Desk(top). Click here to see the other articles in this series.

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Copyright: Asian Scientist Magazine; Photo: Shutterstock.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Rebecca did her PhD at the National University of Singapore where she studied how macrophages integrate multiple signals from the toll-like receptor system. She was formerly the editor-in-chief of Asian Scientist Magazine.

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