Asked by: Derek Smyth, by email
Definitely not. Vitamins are micronutrients. Your body needs them in small quantities to ensure optimum health, but they don’t comprise the bulk of the food you need to survive. For that you need the correct mixture of carbohydrates, fats and proteins.
A multivitamin tablet does normally contain a small amount of starch, and some protein in the form of brewer’s yeast. But to get enough calories to survive, you would need to eat a couple of thousand tablets per day. And if you tried doing that, the huge dose of vitamin A would cause liver failure, long before you noticed malnutrition from the missing fatty acids. If you stuck to the recommended dose of one or two tablets per day, you would simply starve to death in about six weeks.
Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.