What Are Peptides?

A peptide is a short string of amino acids, 2 to 50 long. Peptide molecules are joined by a condensation reaction (a reaction that joins two molecules into one) through a covalent bond (a bond in which the joining atoms share electrons). Such subsequent covalent bonds form peptide chains and are the building blocks of proteins.

Peptides are not just some esoteric molecules floating around in our body, they play a vital role in many of the natural processes and are necessary to ensure it functions properly. The most well-known such peptide is insulin.

Insulin is a 51 amino acid long, naturally occurring peptide hormone produced in the pancreas, essential for controlling blood glucose levels, energy, and fat storage.

Other body’s naturally occurring peptides are:

• Glucagon – a 29 amino acid long peptide hormone, also secreted in the pancreas and helps our body regulate blood glucose levels.
• Endothelin – a 21 amino acid long peptide produced by the endothelial cells, vascular smooth, macrophages (a type of white blood cells), and renal medulla (innermost part of the kidney). Its primary role is vasoconstriction – constricting the blood vessels and raising the blood pressure.
• Somatostatin – a 14 amino acid long peptide hormone known for its GI (gastrointestinal) regulation potential as well as growth hormone inhibition.
• Oxytocin – a 9 amino acid long peptide whose main role is to stimulate uterine contraction during childbirth as well as lactation after giving birth.
• Bradykinin – also a 9 amino acid long peptide that plays a vital role in inflammation as it’s a mediator of vasodilation, which leads to increased blood flow, followed by redness and warmth.
• Ghrelin – a 28 amino acid long peptide hormone that signals your brain when your stomach is empty and when it’s time to eat.

These are just some of the most well-known, naturally occurring peptides within the human body; in reality, there are more than 7400 different peptide types (discovered so far), which is why it’s no surprise why everybody’s so focused on researching peptides and finding a way to incorporate them into a new type of medication.

Is There A Difference Between Peptides and Proteins?

We said that both peptides and proteins are built up of strings of amino acids held together by peptide bonds, so… are they the same thing? 

Yes and no… let us explain. In scientific circles, definitions of this matter are a bit loose. Generally speaking, a difference between peptides and proteins is that the former are generally shorter amino acid chains (of 2 to 50); anything over that is considered a protein. Also, there are differences in structure because, with increased length, protein structures become more complex.

To make things just a bit more complex, we can divide peptides further into the following groups:

1. Oligopeptides – composed of between 2 and 20 amino acids
2. Polypeptides – where amino acid chain length is between 20 and 50

In layman terms, we can classify proteins as really long peptides with many amino acids; or a group of one or more polypeptides joined together. 

Peptides In Food?

Though we are talking about peptides as an essential molecule within the human body, it’s important to note they are also found elsewhere. Peptides are also naturally found in the food we eat. Foods such as:

• Meat
• Fish
• Soy
• Oats
• Wheat etc.

Until recently, proteins (and peptides) in our food were only talked about in the context of nutritional value, but over the years, scientific discoveries have shown they can also modulate our bodily functions. In other words, peptides in foods were also found to interact with the naturally occurring compounds within our body and were studied for their potential in treating and managing chronic diseases. 

Though we are still far away from any definitive conclusions, research shows there is significant potential.

Are Peptides All That They Claim To Be?

Over the last several years, there’s been a lot of fuss about peptides, especially lately… is it justified, or just a marketing fab?

According to renowned biochemists and scientific researchers, peptides are the next big thing. 

This is primarily due to two interesting peptide’s mechanism of action:  

• More precise hormone targeting and
• Interaction with the exact hormone receptors

Though these mechanisms might not seem like much to laymen, scientists regard them as the most significant in the research for precise targeting with minimal side effects. 

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