Noticed this today in a newsletter I get:

"A study conducted at the University of North Carolina determined that taking a multivitamin and mineral supplement every day significantly reduces infection rates—particularly in individuals with type 2 diabetes.

During the one-year study, 93 percent of the participants with type 2 who took a placebo reported an infection, compared with only 17 percent of those with type 2 who took the vitamin and mineral supplement. Of the 130 adults in the study, 51 had type 2 diabetes.

The researchers believe that the supplements may help because people with type 2 diabetes are at risk both for vitamin and mineral deficiency and for certain types of infection. They caution that a larger study is needed to determine whether these results can be replicated.

-Annals of Internal Medicine, March 4, 2003"

I would think 130 adults (and only 51 with type 2) is too small of a study cohort to be completely valid and I guess that is their conclusion as well. Will be interesting to see if this is followed up though with larger study.