Doctor s Best Pure Collagen Types 1 and 3 contains pure collagen protein which contributes to the growth and maintenance of healthy tissues.* Collagen is the structural protein essential for the strength of bones and flexibility of joints tendons ligaments hair skin nails and other tissues throughout the body.* Collagen Types 1 and 3 Powder is enzymatically hydrolyzed into component peptides with a small molecular size for optimal absorption and utilization by the body.* At Doctor?s Best we lead with science. Our products are backed by research and crafted using pure ingredients carefully sourced from around the globe. Since 1990 we have dedicated ourselves to providing highly effective nutritional supplements that enable you to live a healthier lifestyle. We want nothing more than to see you and your family thrive!