What Are Multivitamins?
Multivitamin supplements are a multi-billion dollar industry, being sold over the counter in almost every pharmacy and grocery store throughout the world. Everyone either takes multivitamins themselves or knows someone who does, but are they effective?
Interestingly, unlike medications, multivitamins are classed as a supplement, not a drug and as such do not require FDA approval. This means that they can be sold without any vigorous scientific testing and claims on packaging require no supporting evidence. This could lead to potentially useless or even toxic substances being sold to the public, resulting in unnecessary expenditure or even harm to health.
Before we delve into the subject of whether multivitamins are effective when taken as a supplement, we must first understand what is meant by the word Vitamin.
“A Vitamin is an organic compound that is required by organisms in small amounts to ensure normal growth and nutrition, as they cannot be synthesised themselves by the body.”
Interestingly what is classed as a vitamin for one organism may not be for another as some organisms can synthesise the compounds another can’t. A classic example would be vitamin C (ascorbic acid) which can be made by many mammals but not by humans.
Is Supplementing in Vitamins Beneficial?
Vitamin supplements are by no means ineffective. There are several pathological conditions attributed to vitamin deficiency such as Scurvy (Vitamin C), Rickets (Vitamin D), Anaemia (Vitamins B12 and Folate) and many more. These deficiencies can lead to significant health impairment and this can often be treated by simple supplementation in vitamins, which can even be lifesaving.
The question however is not if vitamin supplementation is useful per se, but if supplementing an otherwise healthy individual with a multivitamin is effective as an aid to disease prevention.
Vitamin deficiency in the Western world is generally less prevalent than in third world countries as our diet generally contains higher amounts of vitamins and many foods are fortified to artificially increase the levels of vitamins we eat. There are however certain groups that are at risk of vitamin deficiency such as the elderly, alcoholics, pregnancy and vegans.
Multivitamins vary between brands but generally they contain all vitamins and at levels ranging from 50% to 150% recommended daily allowance (RDA). The cost varies significantly but the base ingredients are often identical. Claims that one brand is better than another are often not substantiated by any science and usually simply a marketing tactic.
Is There Any Scientific Evidence?
The truth is that in the medical field it is generally believed that supplementing a healthy individual with a multivitamin is not beneficial to health. A 2013 review performed for the United States Preventative Task Force found limited evidence to support any benefit of vitamin supplementation in preventing cancer or cardiovascular disease or improving lifespan.
Another randomized control trial showed that long term supplementation in multivitamins made no difference to the memory function of men later in life. In addition to studies looking at the benefit of multivitamins in specific conditions, a large systematic review of the overall benefits of supplementing with a multivitamin revealed that there was no evidence that supplementation provided any benefit when compared to a balanced healthy diet.
So the evidence basically concludes that there is no evidence that supplementing in a multivitamin is beneficial to the health of an already healthy individual. So the next important question is whether multivitamin supplementation could be harmful?
Are Multivitamins Safe?
On the whole supplementing in a standard multivitamin is considered “safe”. There is however significant risk of harm in supplementation with individual vitamins that may be available in very high concentrations. The same risk is possible if taking several multivitamins, even though the dose in each individual tablet is safe. Some studies have even showing that supplementing in vitamins can even result in reduced lifespan.
So in conclusion there is no real evidence to support the notion that supplementing an otherwise healthy individual with a multivitamin confers any health benefit. There is however little evidence to say that supplementing in a single multivitamin a day adds any risk, so it is really down the individual as to whether they decide to spend their money on possibly unnecessary supplements.
The term ‘healthy individual’ does not relate to everyone however, and those at risk of vitamin deficiency such as the elderly, pregnant women, vegans and those with certain illnesses will often benefit from supplementation with either a multivitamin or specific individual preparations, and you should see your Physician to see if this applies to you.
If you are interested in the subject of supplements you may enjoy reading the truth behind fish oil supplements.