During an interview the other day, I was asked whether multivitamin supplementation was necessary or even beneficial. Although it’d be nice to have a definitive answer to both those questions, like most other aspects of nutrition, the answer is usually “it depends”.
A lot of time and words have been spent debating the relative merits of multivitamins. The common argument against multivitamin use is that people can meet all their nutrient needs from food alone. This statement presupposes two things: 1) nutrient needs are defined as the amounts required to prevent acute disease (i.e. rickets, scurvy, or pellagra) and 2) most people are willing to eat a healthy diet.
In reality, gearing nutrient recommendations towards the prevention of acute disease is a little shortsighted. Although our dietary recommendations do keep people from suffering the immediate, ill-effects of insufficient vitamin and mineral intake, there is growing evidence that many of our current recommended intake levels are insufficient for the prevention of chronic diseases such as cancer or heart disease.
Take for example, vitamin D. Our current recommended intake of vitamin D is 400 IU, which we’ve determined to be adequate to prevent rickets. However, general consensus is that vitamin D intake at the level of 1000-2000 IU is optimal for cancer prevention. Given a glass of milk only provide 100 IU of vitamin D (1/10th the required amount) and that most people aren’t salivating at the prospect of consuming the three cans of sardines daily needed to cross the 1000 IU threshold, opting to go the supplement route starts to sound a whole lot more appealing.
A second problem with saying that people can get all the vitamins and minerals they need from food is that they don’t. Astonishing as it may sound, as many as 35% of North Americans are not even consuming the 5 servings of vegetables and a fruit a day considered to be the MINIMUM requirement. Clearly, the “eat healthy” message has yet to sink in for many North Americans. Considering we can’t convince people to do the bare minimum, getting people to consume enough vegetables and fruit to optimize health is likely a pipe-dream.
Even the conservative American Medical Association has changed their anti-multivitamin stance in 2002 to endorse the utility of multivitamin supplementation in the war against chronic disease. But simply recognizing multivitamins as potentially beneficial is not enough, people need guidance in making proper choices.
One of the problems with supplements of any type is the issue of quality. Just as the “beef” in a McDonalds hamburger is a very different animal than grass-fed, organic, free-range beef (pun fully intended), the quality of many supplements lining the shelves tends to be quite variable. Remember, just because you can buy 240 multivitamin pills for $15, doesn’t mean you should. Quality comes at a price, whether we are referring to food or supplements.
Many cheap supplements are cheap for a reason. They may not contain what they claim to on the label, they may be providing an inferior form of the supplement in question or they may contain such a low dose of the active ingredient that no possible benefit could ever be obtained even if you were to consume the entire bottle in a single sitting (warning, don’t ever consume a whole bottle of anything just to test this theory).
An additional consideration is absorption. People in the nutrition business love the phrase, “you are what you eat”. Not a bad saying, however in the interests of accuracy it should be, “you are what you absorb”. If you aren’t absorbing your food or supplements properly, then you are flushing money and potential health benefits down the drain. Considering vitamins and minerals, minerals in particular, are poorly absorbed at the best of times, the issue of bioavailability is a very real concern.
One of the most useful reviews I have come across on the topic of multivitamins is the Multivitamin Guide, written by Lyle MacWilliams (download available here: Multivitamin Guide: 2009 Edition). In the guide, McWilliams has short-listed 510 multivitamin formulations currently sold in Canada and the US. and gives each product a percentage ranking out of 100. He bases his rankings on a number of factors including:
|Completeness||Potency||Bioavailability||Bioactivity of Vitamin E|
|Cardiac Health Triad||Homocysteine reduction triad||Bone Health Complex||Antioxidant triad|
|Glutathione support||Metabolic support||Bioflavanoid profile||Phenolic compound profile|
|Lipotropic profile||Potential toxicities|
Out of the 510 products he tested, a mere 8 scored higher than 80%. His top 4 formulations: Essentials by USANA Health Sciences, Ultra Preventative X by Douglas Laboratories, Extend Plus by Vitamin Research Products and Life Force Multiple by Source Naturals are superior products offering considerable benefit. Unfortunately, none of these products can be considered cheap, as the cost per day ranges from $1.50-$2.50. While these products might exceed the budget of most people, keep in mind they back up their costs with high standards of purity and bioavailability.
Among the guide’s most eye-opening findings was that the majority of the popular “one a day” tablets were essentially worthless. Manufacturers such as Centrum, Jamieson, Equate, Kirkland, Life, and One a Day all scored pretty abysmally, with GNC not doing much better. These products scored so poorly, it’s not a stretch to say they add little benefit to anyone’s diet and should largely be avoided.
Therefore, to answer those questions from earlier, are multivitamins beneficial or necessary? In terms of benefit the answer should be: no, not if you are buying a cheap multivitamin. If, however, you are opting for a high-quality multivitamin, your health stands to benefit in a meaningful way.
As to whether multivitamins are necessary, let me put it this way. If your diet consists predominantly of pesticide-free, in-season vegetables and fruits, sprouted grains and a proper complement of organically-raised, pasture-fed animal proteins, then you’re pretty set from a vitamin and mineral perspective. Alternatively, if you tend to be a creature of habit who eats the same foods every day and whose diet contains a meaningful percentage of processed foods, then adding a high-quality multivitamin is a wise investment.
Remember, your goal should always be to focus on food first and supplements second. No pill in the world will undo a steady diet of deep fried candy bars and Frappamocachocolatto frozen beverages. But with today’s radically altered food supply, increasing environmental toxins and constant stressors, a high-quality multivitamin can help “fill-in the cracks” in anyone’s diet.
Making it a priority to invest in high quality foods and supplements is a smart decision. Even if you aren’t prepared to shell out $2 a day for a multivitamin, there are many products available to suit everyone’s tastes and budgets. To assist you in making an informed decision, I strongly recommend the Multivitamin Guide as the place to start.