Because the chemicals in them would damage your skin because of the structure of your skin cells.
Usually things overloading your life
Answer: B) thiamin
Explanation:
Thiamine (vitamin B1) acts on carbohydrate, fat and protein metabolism, acting as a coenzyme - thiamine diphosphate. This , in combination with phosphorus, forms coenzyme thiamine pyrophosphate (TPP), which is the key to various reactions such as the transformation of glucose into energy (ATP). TPP acts as a coenzyme in the oxidative decarboxylation of pyruvate, forming acetate and acetyl coenzyme A that is required for carbohydrate, fat and protein metabolism.
