Peptide Therapy Is Big Business. But Can You Get Peptides From Foods?

Depending on your source of health news or the slant of your social media feed, you might be getting inundated these days with info about peptide therapy. This medical treatment involves using peptides — aka small chains of amino acids — to address health concerns like high blood pressure, aging skin, and elevated inflammation.

Some common peptides include insulin, collagen, and glutathione. Delivered via oral supplements, skincare products, and injectables, they bind to receptors on the surface of cells. There, they can mimic human hormones, growth factors, neurotransmitters, or anti-infective agents — hence their beneficial potential.

If you know a little biology, you might recognize amino acids as the building blocks of dietary protein. So does this mean you can reap peptides’ benefits simply by putting the right foods on your plate? Stick with us as we dig into the science behind dietary peptides.

How are peptides different from proteins?

Peptides are similar to proteins, but the two aren’t exactly the same thing. “While amino acids are the building blocks that make up proteins, peptides are essentially smaller, simpler forms of proteins,” explains Katherine Maslen, ND, naturopathic doctor and host of The Shift Podcast. “Peptides contain around 2-50 amino acids, whereas proteins contain over 50 amino acids.” Because of their shorter length, peptides may be easier for the body to absorb than proteins.

Besides their difference in size, peptides and proteins also perform different functions in the body. “Peptides can act as signaling molecules for things like hormones or neurotransmitters, and usually have specific and targeted functions,” Maslen says. Some functions of peptides include insulin’s ability to regulate blood sugar and collagen’s promotion of youthful-looking skin. Proteins, on the other hand, build muscle tissue and act as antibodies that fight illness.

Another difference: public health parameters around protein intake are well-defined (such as the Acceptable Macronutrient Distribution Range of 10-35% of daily calories from protein). The same can’t be said for peptides. They have no set recommended intake.

So… can you get peptides from foods?

Medical treatments and OTC supplements don’t own the market on peptides. Many are found in everyday foods!

“Since peptides are a derivative of protein, a protein-rich diet will supply an adequate amount of peptides,” says Maslen. Beef, lamb, chicken, fish, eggs, and dairy are animal sources. Whole grains, legumes, nuts, and seeds provide peptides in plant form.

According to Maslen, one of the best sources is the marine collagen in fish and seafood. “It is easily broken down into collagen peptides, which are highly bioavailable,” she says. “These can help to improve tissue health, skin health, joints and gut health.”

Legumes and cereals are another top food for peptides. “Lunasin, a peptide found in soy and some cereal grains like barley, oats, and rye may have anti-cancer properties, according to studies,” Maslen says. “Fermented dairy (like yogurt, kefir, and fermented cheeses) contain bioactive peptides that can support gut health, immune health, and cardiovascular health.”

The effects of peptides in foods versus other sources

Since peptides are found in certain foods, it begs the question: can eating them have the same effect on health as, say, getting a peptide injection or applying a peptide cream? Yes and no.

On the one hand, Maslen says eating foods that contain peptides is a smart choice, since they typically contain nutrients and phytochemicals you won’t get from peptides in isolation. A serving of salmon, for example, not only contains marine collagen. It also provides vitamin D to support immune function and omega-3 fats for heart health.

That said, the effectiveness of peptides in foods may vary, based on how easily your body absorbs them. “The issue is that the bioavailability of food-derived peptides could be lower because digestion may break them down into amino acids before they can exert their specific functions,” Maslen say. “Therefore, they may not give you what you’re looking for.” She adds that the health impact of food-derived peptides could also differ from person to person.

Peptides in the form of supplements, injections, or creams, however, are typically hydrolyzed. This means their chemical bonds are already broken down — a process you can think of as pre-digestion. “Because they are pre-digested, they could possibly deliver peptides directly into the bloodstream without requiring extensive digestion,” says Maslen. “This higher bioavailability means that the body can absorb them more efficiently so you have a higher chance of achieving the desired effect.”

Many peptides are even found in synthetic forms in pharmaceuticals. These are, of course, far more powerful than foods. Synthetic oxytocin, vasopressin, and recombinant human insulin are peptides that have been used in medicine for decades, Maslen says. More recently, medical peptides have gained widespread fame in semaglutide weight loss drugs, which use peptides that mimic gut hormones.

Takeaway

If you’re considering peptide therapy for a specific health issue, talk to your doctor about whether dietary adjustments might be a first line of defense. It’s possible that a nutritious diet could point you in the right direction without the need for pricy peptide supplements.