At present, there were many collagen products in markets, but their quality was uneven. Some were used for injection, some for oral, the others for external, but most of them were made from animal collagen.
Firstly, because animal collagen was water insoluble, the final water soluble products extracted by any way weren't the essential collagen and they lost the cosmetic function; acid- solved collagen product could led to side -effect to skin or body.
Secondly, animal collagen had a drawback----the potential risk of virus in animal and contaminated with heavy metals.
Finally, animal collagen could be little absorbed and it was not easy to unify and to stabilize the product's standard and quality.
Hence, we shall instead eating food rich in antioxidants to stimulate collagen production in our body.
