Collagen is the glue that holds your body together. We have lots of types of collagen but most are type I.<\/p>\n
Type I collagen, external<\/a> gives skin shape and strength, but it starts to break down faster than your body can replace it in your mid-20s. At this age, skin begins to lose thickness and strength at a rate of around 1.5% a year, according to consultant dermatologist and author of The Skincare Bible, Dr Anjali Mahto, external<\/a>. <\/p>\n That’s why collagen is a popular ingredient in skin creams, but there’s a question about whether it can actually penetrate the epidermis (outer layer of skin). <\/p>\n Injecting collagen isn’t a surefire win for your skin either, as it doesn’t last as long as some alternative fillers and has been associated with complications like allergic reactions.<\/p>\n