Sports and health enthusiasts are constantly throwing vitamin and mineral supplements down their necks but the issue of whether they are really required is a topic of considerable debate.
Vitamins and minerals, or micronutrients, are essential nutrients, as, broadly speaking, our bodies do not synthesise them, and so we have to obtain them from our food. Micronutrients regulate metabolism and assist in numerous physiological and biochemical functions. Insufficient intakes may lead to deficiency problems, and in extreme cases, even death.
If you are eating a healthy balanced and varied diet, then the evidence indicates, in most cases, you’ll be okay with no need for a supplement. Most alternative nutritionists will claim that you do need supplements for ‘optimum’ health and to ‘just to make sure you’re getting enough’.
There has been loads of scientific research into the debate to see if supplementation over and above what you get from your normal diet is required in order to reduce risk of disease and/or maximise performance. In a few cases the research is conclusive and supplements are recommended, e.g. folic acid in pregnancy to reduce the risk of spina bifida in the child. But it is only certain people that do have a use for supplements; does this include all of us?
Sports enthusiasts are traditionalists for mega-dosing without any real reason for doing it. Beware that certain vitamins can have harmful side effects if taken in too large quantities. Vitamin C is frequently mega-dosed on, but are you aware that too much for long a period can lead to kidney stones? As vitamin C is water soluble, people have the misconception that you cannot take too much – this is wrong!
There are other examples: There have been cases of death from too much vitamin A; rare, but there are many reports of hair loss, liver and bone damage. Excess thiamine (vitamin B1) can cause headaches and irritability. Too much vitamin D can cause too high blood calcium levels, potentially causing muscle spasms. Consuming too much sodium raises blood pressure. Mega-doses of iron can be lethal, as iron levels are only controlled by what you eat, absorbed and what comes out when you bleed. Zinc in high amounts can cause nausea and vomiting. There are many cases of excess iodine intake causing goitre (an enlarged thyroid gland, making the neck swell up) and hyperthyroidism, i.e. a racing metabolism. Too much fluoride can cause tooth and nail crumbling. These are just a few examples!
Many vitamins and minerals are consumed in high doses for their antioxidant effects. Vitamins C and E, beta-carotene and selenium are antioxidants, which have been shown to reduce incidence of heart disease and some cancers. Antioxidants help stop the oxidation process, which is part of the process of certain diseases and aging. People therefore believe that consuming more of these antioxidants more means reducing risk of disease further (and looking younger!). But, studies have shown that there are optimal intake levels, and these levels are well below what many people supplement with.
If your diet is deficient in a particular vitamin or mineral, then there may be a case for supplementation; but this is only if there are subnormal levels being consumed. I recommend that most people eat a varied healthy balanced diet, with at least five servings of fruit and vegetables daily – more if possible. In certain circumstances, there may be a case for supplements, but in general a healthy diet should cover all. So before you order more vitamin and mineral supplements, first check your diet and eat more fruit and vegetables!