Collagen, which is found in all mammals, is the main component of muscle, skin and connective tissue.
The protein is an essential building block for collagen-producing cells.
It is found naturally in skin, hair, nails and nails and is also found in some products.
But the protein does not have the same properties as collagen found in the human body.
For some people, collagen can cause the condition collagen cystitis, where the collagen breaks down and causes damage to surrounding tissues.
“It is a condition that people may experience with their hair, where they start to feel very weak and have a swelling around their mouth, especially around their teeth,” Dr Vincenzo Marotta, a medical doctor and head of the clinical research unit at University College London, said.
“This is known as ‘hair-dry’ or ‘dry skin’.” A lack of collagen can also lead to a number of problems including: swelling of the jaw, throat, tongue, ears and eyes