Can taking vitamins shorten your life?
Answers: The only way I can see that happening is by overdosing on a vitamin. Whether it's possible to overdose depends on the vitamin (see http://inhumanexperiment.blogspot.com/se... for some experiments and discussion on this).
If you're taking water-soluble vitamins such as C and B, for example, chances are you're increasing and not shortening your life span. You can take ridiculous amounts of vitamin C and not have side effects.
You can, however, get too much vitamin A. It can even be deadly if taken in high amounts, but I don't think there's a product out there that would contain that much. You'd have to take several vitamin products each day. Or eat seal liver.
In short: yes, but it's highly unlikely.
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