Vitamin Super C supplements contain extreme doses of vitamin c that are way higher than a human should consume daily, unless they have some precondition. Took them for maybe 4 days. Couldn't even swallow them and so I had to chew them, read in the Nature Made website that unless the product otherwise indicated you can chew any of their supplements if you must, so that's not the problem because it wasn't indicated that these are slow release or dangerous to chew. A few days in had Diarrhea. Really smelly pee, and even cloudy eyes that made me think that taking these putrid vitamins had given me cataracts. Read up more and found out that extreme amounts of vitamin c can cause these symptoms, alongside kidney stones and other unpleasant medical situations. The recommended amount of vitamin C adults are recommended to take is 65 to 90 mg a day. These are 900 mg and when you consider how it takes about 10-20 days at the very least to get it out of your system, these are dangerous pills unless you have some kind of condition. These need a warning label that lists possible side effects