Hey ,
I hope you enjoyed your summer! Good to have you back 🙂
Peptides are a short string of amino acids. For example, glutathione is a peptide made of 3 amino acids and is therefore called a tripeptide. Creatine is also a peptide. Secretly you already know a few peptides.
There is no real good answer to your question since there are many peptides with different kinds of roles in the body. Consider amino acids as Lego building blocks. Depending on how you connect the blocks, the function can differ.
GABA is for example a “neuropeptide” which is made of glutamate and a glutamate variation attached under the influence of vitamin B6. GABA is an example of a neurotransmitter. But even hormones can be peptides. Examples of peptide hormones are for example insulin, glucagon and prolactin.
Collagen peptides are often used for skin, hair and nail health. The function can therefore vary considerably.
Here are some peptides sold as supplements that are lesser known
BPC-157 is a peptide that is often used for joint recovery. NMN is a peptide which is an intermediaire of NAD+.
Maybe you could specify what supplements you are curious to?