Fish scale, fish skin, pigskin and bovine bone collagen, which is better? Seek an answer

Comparatively speaking, fish collagen is better. Fish collagen refers to collagen extracted from the skin or scales of deep-sea fish, and the other is collagen extracted from bones, cattle bones and pig bones. Deep-sea fish are less polluted, while cattle and pigs are generally fed with feed, which contains hormones and the like, and the purity is not high, which will affect the purity of collagen, so if customers want to supplement collagen, it is best to supplement fish collagen.