Carotene. Besides adding a colorful excitement to foods, this chemical compound - unlike the other major fruit and vegetable pigments - is a valuable nutrient. Because it is a provitamin A, it can be converted by your body into vitamin A. If you've ever seen a vegetarian with a yellow skin tone, he may be suffering from hypercarotenum. It is often caused by consuming vast amounts of carrots or carrot juice. Some of the carotene overdose is deposited in the fatty tissue beneath the skin.