d-biotin versus biotin D-Biotin is the naturally occurring biologically active form of the B vitamin biotin. It involves the metabolism of lipids, proteins and carbohydrates.

D-Biotin is a water-soluble vitamin in eight forms, biotin, also known as vitamin B7. It is a coenzyme-or auxiliary enzyme-used in many metabolic reactions in the body. D-Biotin participates in lipid and protein metabolism and helps convert food into glucose, which the body can use as energy. It is also important for maintaining skin, hair and mucous membranes.