If one were to google for "one a day" "side effect" one would find the first relevant match to be this: http://www.pricetool.com/content_101207477892. I've been taking those vitamins for a week and a half or so. Towards the bottom one might read "Infrequently, chromium has been reported to cause changes in sleep patterns, such as insomnia and increased dream activity. Irritability is another reported side effect of chromium therapy." Hey, insomnia, I have that. Let's see what else we can find. chromium "side effect" leads one to http://www.healthandage.com/html/res/com/ConsSupplements/SideEffects/Chromiumcs.html, which shows itching and other not so nice side effects that the one-a-day people didn't bother putting on their package.
So it looks like no more pills for me; because I'd like to be able to sleep, and stop scratching.