My response to two recently published studies using a multivitamin: “Oral High-Dose Multivitamins and Minerals After Myocardial Infarction: A Randomized Trial” and “Long-Term Multivitamin Supplementation and Cognitive Function in Men: A Randomized Trial”
By Shawn Meirovici N.D.
In the latest issue of “The Journal of Annals of Internal Medicine” two studies investigated the effect of taking a long-term multivitamin on cardiovascular health and cognitive function. The two studies demonstrated that there was no significant effect on either group as compared with placebo. There were no serious side effects and the author’s mention a few limitations in the studies such as: considerable non-adherence, withdrawal and incorrect dosage.
A multivitamin is a single supplement containing a collection of vitamins and minerals, at a dose reflective of the RDI or the “recommended daily intake”. The average individual eating a well-balanced diet will typically obtain the RDI of most vitamins and minerals from their diet. When an individual is unable to eat a healthy well-balanced diet or has an illness compromising the absorption of vitamins and minerals from the diet, they may benefit from a multivitamin. Not only does this concept make sense, it is also supported by many studies investigating multivitamin support on patient populations with know nutrient deficiencies (Effect of vitamin and trace-element supplementation on immune responses and infection in elderly subjecttR.K. Chandra, FRCPC (Prof). )
It is not surprising that nothing statistically significant was observed in the two studies up for discussion. The two patient populations are: a group of individuals who have suffered a heart attack in the past, and a group of ageing, otherwise healthy, men. We do not know the specifics of their diet or if they have any significant nutrient deficiencies.
When not prescribed for a specific purpose a multivitamin acts as a “shotgun blast”, hoping to hit something significant but often missing the point and with limited power per hit. When it comes to supplements, patients will only benefit from specific nutrients, for specific concerns at a specific dosage. For instance: the one study investigating a group of individuals with a history of cardiovascular disease, may have benefitted from specific nutrients designed at lowering blood pressure, balancing blood sugar and improving vessel integrity.
The real controversy surrounding these recent publications is with the Media’s over-generalization of these findings. Here is a headline from CBC News “Vitamin pills ‘should be avoided,’ journal editors say”. The issue here is that the public is lead to believe that all vitamins are always bad, or a waste of money in every circumstance. The truth is that every individual is different in nutritional requirements, health history and healthcare needs. In medicine the adage “one size fits all” hardly ever is applicable. As a naturopathic doctor it is my job to investigate what my patients individual needs are and to give the appropriate medical advise, which often includes vitamins, but specific vitamins at specific dosages for specific concerns.
These studies demonstrate the need for healthcare practitioners, such as: Naturopathic Doctors, and Nutritionists, who are qualified to guide the average consumer as to what sort of supplement may be helpful and which supplements may very well be a waste of money.