Last week I wrote about how new, major studies of certain vitamins showed no evidence that they prevented cancer or chronic disease. (That story is here: http://tinyurl.com/dcsk5u). But the results of two studies released this week were more promising where vitamin D and calcium are concerned. Vitamin and mineral research is very complicated -- with results weighed differently depending on the study methodology -- but as a consumer, it's to your advantage to know about the latest research and make decisions based on all of the information.