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Guide Health: Dietary supplements —should you or shouldn’t you?

A Consumer Reports panel has identified 15 supplements to avoid. Check the ingredient lists on the products you take. Toxicities can be significant

Close up view of young woman holding ginseng vitamins and minerals pills in hand with capsule bottle on table. High angle view

Dietary supplements provide additional nutrition to your diet. Most often, the term may make you think of vitamins and minerals, but natural products and herbal remedies are also part of this category.

Should you buy them?

Vitamins are organic substances from plants or animals that your body needs in small amounts. Minerals are needed in small amounts too, but come from inorganic sources.

Luckily, an average diet usually contains sufficient vitamins and minerals.

“Natural products” are simply substances obtained from organic sources. Their variety is wide, including bee pollen, soy-based products and flaxseeds, as well as herbal remedies that usually originate from plant material.

While defining supplements can be confusing, however, it is clear that they are popular. About two-thirds of Canadians use them, with about 30 per cent taking multiple vitamin products.

Keep in mind that these numbers do not include the therapeutic use of supplements, such as the use of calcium for a diagnosis of osteoporosis, or iron for a diagnosis of anemia.

In Canada, supplements are regulated by the Canada Natural and Non Prescription Health Products Act of 2004. The aim of the legislation is to ensure that supplements are safe to use, that they are manufactured in a clean and safe manner, and that they contain the ingredients that they are supposed to contain.

If you have a problem with a supplement, there are provisions for you to be able to report adverse reactions, as well as provisions for the manufacturer to recall a defective batch of product.

Before you take a supplement, check your diet. Keep a food diary for several weeks and read your food labels. This may reveal that you are already obtaining the nutrients you need.

If you do take a supplement, find out exactly what it is supposed to do for your health and what dose is needed to produce the benefit. For example, almond milk is a good source of calcium, but unless it is fortified, it does not contain as much calcium as milk. Obviously, then, you would choose the fortified almond milk!

Keep in mind that supplements are just that; they “supplement” your other healthy-living choices and any medications you may take.

So, for example, if you have high cholesterol, you wouldn’t stop eating a low-fat, high-fibre diet or taking your cholesterol-lowering medication when you start a fish oil supplement.

It is also important that you tell your doctor, nurse, and pharmacist about any supplements that you may take. They will help you identify potential side-effects and drug interactions, and even whether the product is safe for you.

Because many supplements are plant based, allergies are a potential risk. These allergies can sometimes be severe, especially if you have a pre-existing allergy like hay fever.

A recent article in Consumer Reports listed 15 supplements that its panel of experts say should always be avoided: aconite, caffeine powder, chaparral, coltsfoot, comfrey, germander, greater celandine, green tea extract powder, kava, lobelia, methylsynephrine, pennyroyal oil, red yeast rice, usnic acid, and yohimbe.

It’s a good idea to check supplement labels for these ingredients because adverse effects and toxicities can be significant.

Some supplements are widely advertised, but if the claims seem too good to be true, they probably are.

Knowledge is key when it comes to supplement use, but the information needs to be of good quality. A discussion from the Heart and Stroke Foundation about the cardiovascular effects of fish oils is certainly of better calibre than a website that is trying to sell you a fish oil supplement.

Supplements may be part of your overall health plan, but be smart about using them.

About the author


Marie Berry is a lawyer/pharmacist interested in health and education.



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