The human digestion is a slow process catalyzed by digestive enzymes. Short collagen chains can be absorbed quickly into the blood stream while longer collagen chains are too big to be absorbed and are mixed with the digestive enzymes and broken down into peptides. Collagen hydrolysate are made by using heat or acid to controllably partially digest long collagen fibrils into shorter chains for fast absorption. Aging skin produces less collagen. The wrinkling we see on old people's faces are caused by this change in the material composition of their skin. The short collagen chains travel through the blood stream to the skin and are incorporated into cell-produced collagen fibers, making up for the loss of collagen production caused by aging.
I_Fap_To_LoL_Champs t1_je18oyi wrote
Reply to ELI5: if protein is broken down into peptides in the stomach/digestive tract, why would consuming something like "active collagen" do anything? by Alexander_Elysia
There is in fact a lot of animal and clinical evidence that supports collagen hydrolysate (assuming this is what you meant by active collagen) supplementation for skin aging: Recent progress in preventive effect of collagen peptides on photoaging skin and action mechanism
The human digestion is a slow process catalyzed by digestive enzymes. Short collagen chains can be absorbed quickly into the blood stream while longer collagen chains are too big to be absorbed and are mixed with the digestive enzymes and broken down into peptides. Collagen hydrolysate are made by using heat or acid to controllably partially digest long collagen fibrils into shorter chains for fast absorption. Aging skin produces less collagen. The wrinkling we see on old people's faces are caused by this change in the material composition of their skin. The short collagen chains travel through the blood stream to the skin and are incorporated into cell-produced collagen fibers, making up for the loss of collagen production caused by aging.