Collagen is a fibrous protein that makes up the connective tissues like the bones, cartilages, skin, hair, and nails. It makes up about 25% of all proteins in the body, making it the most abundant and most important protein for human health. Doctor?s Best Collagen Types 1 & 3 Powder contains pure collagen that supports the growth and maintenance of these connective tissues. It provides the body with the raw materials needed maintain tissue strength and flexibility. visit us : http://www.tasmanhealth.co.nz/doctors-best-collage n-types-1-and-3/ for more details!!