Are Vitamin and Mineral Supplements Doing More Harm Than Good?

Vitamins minerals harm

The society we live in today offers us a large abundance and variety of healthy foods that aren’t all that expensive anymore as they once were. Mainly because Europe is a wealthy continent, most of the population can afford these healthy products. For several years now, health has been an important topic for people, and food industries and other related companies have been making the most out of this trend. Wherever you go, healthy food is promoted!

A lot of research focusses on what is healthy and what isn’t. Recently, the scientific community has been looking specifically at vitamins and minerals and their benefits. Because of this, supplements have become a very lucrative business. However, the information we receive about vitamin and mineral supplementation is often contradictory. Big supplement companies promote intake of their products, saying everyone needs more vitamins and minerals. Pharmacists sell a big variety of supplements, which promise to increase your health in specific ways. And there’s usually a supplement for whatever ails you!

Multi-vitamins are especially popular among people, since they promise you a little bit of everything. However, promised positive health effects, like strengthening of your immune system, often have not been sufficiently researched to provide significant evidence.

Vitamins and minerals are micronutrients. Most vitamins and some minerals are essential micronutrients. This means that they cannot be readily synthesized by the body and thus need to be ingested via the diet. A serious deficit of one or more of these essential micronutrients can lead to severe diseases such as heart failure, peripheral neuropathy or dementia. They can also result in symptoms like insomnia or depression.  A deficiency of one of these micronutrients can have serious adverse effects at almost every level in the body.  The abovementioned syndromes are still frequently seen in third world countries, but hardly any more in western societies, since we have enough resources to counter them. Nevertheless, some of them can still occur in special populations such as elderly, vegans, the very poor or people with alcoholism, malabsorption or little sun exposure.

There is, however, a big difference between an actual vitamin or mineral deficiency than just not getting the optimal dose of these micronutrients (called ‘sub-clinical’ deficiency). An actual deficiency can cause real adverse effects that can be harmful.

For optimal human functioning, your body needs access to an adequate amount of nutrients and micronutrients. For people with a normal diet, supplementation is actually not needed, but can contribute to good health. A less than optimal intake of these micronutrients, however, does not necessarily mean that any adverse changes occur. This is because your body is a very versatile and adaptable machine and can adapt very well to multiple situations.

However, higher levels of vitamins or minerals—meaning above the optimal dose—are not necessarily healthier and may even be toxic and cause harm! Due to the complexity and individuality of each person’s metabolism, it isn’t exactly clear what those optimal doses should be for each and every one. Thus, taking vitamin and mineral supplements in high doses may not be good for you.

As with all possible toxic substances, institutes such as the FDA (Food and Drug Administration) in the US, and the EFSA (European Food Safety Authority) in Europe determined upper limits for vitamin and mineral intake per population group. These limits dictate until which amounts these vitamins and minerals are safe. Many people, however, may not take into consideration these upper limits, which may thus be ignored.  They may not know that exceeding this optimal dose would not be beneficial.

While some vitamins in large doses may just pass through the body and get excreted, some can cause severe toxic effects. Excess vitamin A, for example, may cause liver toxicity, while excessive vitamin C can lead to kidney stones.

High doses of minerals also cause toxic effects. Excessive selenium may lead to hair and nail brittleness, while too much phosphorous can result in skeletal porosity and metastatic calcification.

The prospect of measuring the actual vitamin or mineral concentration in the blood has made it possible to investigate actual blood concentrations following dietary supplement intake. However, information currently available is often contradictory, making it hard to decide what supplements you should take, not to mention whether to take them at all!

Whether you need specific vitamins or minerals to supplement your diet is dependent on a lot of factors, such as your diet and metabolism. To be able to accurately decide the need for supplementation, a lot more research is needed. The need for supplementation may vary for each individual. Home monitoring kits for blood vitamins and minerals could be an option, but the question remains if this is really needed.



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