Peptides are short chains of amino acids linked together by peptide bonds. They typically consist of about 2 to 100 amino acids, making them smaller than proteins, which are longer chains of amino acids (usually more than 50)
. Peptides can be linear or cyclic and vary widely in their amino acid sequences, leading to a vast diversity of possible peptides
. In the body, peptides serve many essential functions. For example, insulin is a peptide hormone composed of 51 amino acids that regulates sugar metabolism
. Peptides can act as neurotransmitters, hormones, or signaling molecules that regulate biological processes. Some peptides stimulate collagen production in the skin, aiding in repair and anti-aging effects
. Peptides are naturally present in foods such as eggs, milk, meat, fish, beans, and grains, and they are also made synthetically for medical and cosmetic uses
. Due to their smaller size, peptides are often easier for the body to absorb and can penetrate tissues more readily than larger proteins
. In summary, peptides are biologically important molecules made of amino acid chains shorter than proteins, involved in numerous physiological roles including hormone activity, immune function, and skin health
