I received a great question about whether multivitamins (MVI) are even worth taking because they heard they were not absorbed by the body. Generally dietitians do recommend vitamins for those who are on a restricted diet (for weight loss) or who struggle to get all the necessary nutrients through their diet for one reason or another. If I were to see you in my office I would say any general MVI will do. I do recommend looking for the US Pharmacopoeia certification on the bottle. This is a voluntary certification which the tests for purity, and it tells you the supplement does in fact contain the ingredients which it claims to have. Believe it or not, this is an issue in the supplement world. For a full list of brands with the USP certification, please visit: http://www.usp.org/USPVerified/dietarySupplements/supplements.html .
The issue of absorption is an important one for supplements because some nutrients, in excess, will just be excreted in the urine. In particular, water soluble vitamins have a limited capacity to be stored and are therefore excreted. Water soluble vitamins are vitamin C and the B complex vitamins. Some vitamins offer these nutrients in a “time released” form in hopes that you will not excrete the excess. “Mega” vitamins offers some nutrients in amounts that exceed 100% of the Recommended Dietary Allowance (RDA). I recommend people stay away from these vitamins because vitamin toxicity is a possibility. It is also important to remember that a healthy diet will provide a substantial amount of the nutrients your body needs for good health. I see vitamins as a “safety net.”
There are a lot of specialized and high end supplements available out there that promise many wonderful things. If you are considering one of these, look for one that is supported by several clinical research studies on their particular product. To answer the original question, finding a supplement that shows it is bio-available (it is actually absorbed by the body) would be optimal. I have some personal feelings about this in particular. If you are interested in knowing about them, please post a statement below and I will respond to your email address.
In general, I think vitamins can be a healthy addition to your daily routine. As long as a supplement is generally safe and ethical (based on the above statements) then I believe they are a personal choice. If you feel a high end product is beneficial and safe then I encourage you to continue taking it. If you are happy with your store brand multivitamin, keep taking it!
