Table 3.

The impact of collagen supplementation on individual systems and organs of the human body [17,38,47,63,81,82].

Place of Action	Effect of Supplementation
Immune system	Inhibition of inflammatory processes resulting from autoimmunity.
Hormone system	Amino acids included in collagen may be involved in the production of hormones and neurotransmitters, e.g., GABA.
Cartilage and skeletal system	Increased production of collagen in cartilage—improved resistance to mechanical loads, reduction in joint pain and joint inflammation, stimulation of the production of synovial fluid.
Skin	Bioactive short peptides (dipeptide glycine—hydroxyproline) send signals to fibroblasts, stimulating the collagen production process, reducing wrinkles, improving the smoothness, tension, and elasticity of the skin, reducing cellulite and stretch marks by improving the elasticity and cohesion of the skin.
Hair, nails	Preventing graying and hair loss and brittle nails.
Liver	Assistance in the removal of toxic substances and alcohol metabolites.
Muscle	Increase in muscle mass, increased energy efficiency of the body.
Circulatory system	Amino acids contained in collagen, such as proline and lysine, prevent the accumulation of fats in the walls of arteries—protection of the circulatory system.
Digestive system	The amino acids proline and glycine seal the walls of the small intestine; collagen helps absorb water in the intestines.