Fact: 90% of multi's are crap. There's a book by Lyle MacWilliam called 'comparative guide to nutritional supplements'. He is a biochemist commissioned by the gov't of Canada to write this book. in it he tells what to look for and rates them on a very thorough scale. Only a few of them are worth the $$$. USANA and Douglas labs are the best. Period.
here are the results of a recent study that just further shows how most multis don't make the cut:
Canadian study indicates that quality of nutritional supplements is still a concern
In a new study, researchers discovered that more than half of the nutritional supplements tested did not disintegrate properly. Included in the test were 39 tablets and 10 capsules containing minerals and vitamins commercially available on the Canadian market. USANA's Multimineral was included in the test. The first disintegration stage was performed using Simulated Intestinal Fluid (SIF) pH 6.8 for 20 minutes. Products which did not disintegrate were further analyzed using USP disintegration conditions for dietary supplements. Of the 39 tablets tested, only 18 products (which included Usana's Multimineral) disintegrated fully at the first stage. The 21 tablets that did not pass the first stage were then tested for disintegration using USP conditions. Nine tablets still failed to disintegrate, including all three timed-release products tested. Forty-percent of the capsules also failed the first stage, although all ten eventually passed when subjected to USP testing conditions.
This study illustrates that disintegration, one basic indicator of product quality, is still a concern for dietary supplements.
J Pharm Pharmaceut Sci (www.cspsCanada.org) 9(1):40-49, 2006 http://www.ualberta.ca/~csps/JPPS9(1)/Loebenberg.R/tablets.pdf