Question

What's the main function of vitamins, what kind of compound are they?
What happens when a person's diet is low in fat?

Answer 1

there is no "core structure" of vitamins. by definition, they can not by synthesized by humans, but are needed to fulfill crucial functions in metabolism, immun system and other parts of our living.

if a person's diet is low in fat, this might mean nothing, but could indicate a lack at the fat-soluble vitamins A, D, E and K.

Answer 2

there are many functions actually! each vit performs a different function.

Answer 3

Vitamin comes from joining Vital meaning important, and amine which refers to members from the family of nitrogen-containing organic compounds derived from ammonia (NH3).
There are different Vitamins which have different functions.
The main function, in general is to ensure proper functioning of our different body organs. Just as carbohydrates are responsible for providing energy, proteins for building your body cells and fiber for regulation of bowel movements.
Vitamins are either classified as Fat-Soluble (Vitamin A, D, E, and K) and Water-Soluble (Vitamin B1-Thiamin, B2-Riboflavin, B6-Pyridoxine, Folic Acid-Folacin, Vitamin B12-Cobalamin, Vitamin C)
Vitamin A: Mainly responsible for maintaining normal vision. Also helps in reproduction, development of the embryo, growth, and immune system responses.
Vitamin B: B1-Helps in metabolism and supports proper functioning of nerves.
B2-Acts as an antioxidant, also is a part of co-enzymes which are required
for production of energy in body.
B6-Acts as a regulator of blood glucose levels.
B12-Helps in synthesis of new blood cells.
Vitamin C: Mainly functions as an antioxidant, also actively supports development
of the immune system.
Vitamin D: Helps in proper maintenance of bones and regulates calcium levels in blood.
Vitamin E: Antioxidant, and protects cell membranes.
Vitamin K: Synthesizer of proteins responsible for blood coagulation.