Everytime I take this, I start to feel sluggish and tired an hour afterwards. I couldn't figure out what was causing that and started to connected to this at the very end. I didn't think multi-vitamins could cause that, but I looked it up as we all tend to do now and it did say some multi-vitamins we could be taking too much of it. Although this doesn't seem to have high quantity's of the essential vitamins, but maybe my body just doesn't need one of the ingredients in this. It could just be one thing in this that's causing it. I've taken other multi-vitamin brands and I don't have that issue. It's always just this one. I checked to see if others on here had the same issue, but they're just complaining about being nauseous. Um perhaps because you've been taking it on an empty stomach which you're not supposed to do. After taking this daily for five months straight I then started to feel dizzy an hour after taking this. I didn't put it together that it was this until I started to test it out. Then of course I ran to the internet to see if multivitamins can make you dizzy, and they do claim if your body has too much of a particular supplement or vitamin that it can make you feel dizzy and tired. It's possible this built up in my system and taking it daily isn't necessary. There were only a few reviews citing Dizziness, so the possibility of getting that might be on the lower ranges of side effects. I don't know what's in this causing the fatigue and Dizziness. High amounts of Zinc can do that and this has 11 mg., which is the maximum per day, so maybe it's pushing it in this