A US study published last month has added support to the ability of multivitamins to fill in the nutrition gaps of a poor diet. While this is something that many experts in the world of dietary supplements take for granted, it's still commonplace in mainstream press and media to hear them being discredited.
The study used data from the National Health and Nutrition Examination Surveys (NHANES) over a period of time from 2009-2012. The survey results included 10,698 adults, with an even split of males and females. Multivitamin and mineral supplements were defined as containing 9 or more nutrients of interest and excluded single nutrient and other types of supplements.
Frequent use of multivitamin and mineral supplements achieved exactly what manufacturers claimed they would
The study authors reported that frequent use of multivitamin and mineral supplements achieved exactly what the manufacturers of the products claimed they would do i.e. primarily prevent the shortfall of essential nutrients.
The authors wrote:
"Except for calcium, magnesium and vitamin D, the most frequent multivitamin and mineral supplement use virtually eliminated inadequacies of the nutrients examined and was associated with significantly lower odds ratios of deficiency for the examined nutrient bio-markers except for iron. In conclusion, among US adults multivitamin and mineral supplement use is associated with decreased micro-nutrient inadequacies, intakes slightly exceeding the UK for a few nutrients and a lower risk of nutrient deficiencies."
It is often claimed that diet alone should be able to supply the body with all of the nutrients essential for good health and widespread fortification in food has helped to eliminate certain deficiency diseases such as rickets and beriberi but Americans are still consistently coming up short when it comes to the full-spectrum micronutrient intake that could support optimum health.
Lead author Jeffery Blumberg said:
"...there are now 11 underconsumed or shortfall micronutrients - vitamins A, C, D, E, K and folate and choline and the essential minerals calcium, iron, magnesium, and potassium - recognised in the Dieatry Guidelines for Americans 2015-2020. Multivitamin/multi-mineral supplements can help fill many, but not all, of these gaps as illustrated in our recent study of the latest NHANES dataset from 1009-2012."
It's important to note that the study reported those users who were most consistent in their use of multivitamin and mineral supplements derived the most benefit, this equated to 21 days or more out of the month.
Why does the idea persist that multivitamins are a waste of time?
This may be because of the way that health professionals such as dieticians, pharmacists and physicians are taught and trained - many experts in the dietary supplement field have observed that the curricula in these professions present the contribution of supplements to overall nutrient status as a afterthought rather than a cornerstone. Blumberg comments:
"Regrettably, there apperas to be a great tenacity to old ways of thinking - e.g. you can get all the nutrition you need if you just eat a healthy, balanced diet - and then ignoring how most people actually eat and what they actually require... Also, our understanding about higher nutrient requirements for optimal health and wellness grows, particularly among older adults, it is clear that it can be quite difficult to achieve these intakes of selected nutrients from commonly available food choices."