A Nurse Practitioner Just Explained What Peptides Actually Are (and How to Not Get Scammed)

Peptides have officially taken over the wellness world. Celebrities swear by them, athletes credit them with healing injuries, and suddenly everyone you know is “on a stack.” But here’s the thing most people skip: these injections are largely experimental, mostly not FDA-approved, and where you get them genuinely matters.

On GlowLab, host Susan Yara sits down with board-certified nurse practitioner Mercedes “Mimi” Deal to answer the questions most people have but rarely ask, from what peptides actually do to how to find a provider you can trust.

What to Know Before Trying Peptide Injections

First, what even is a peptide?

Simply put, a peptide is a short chain of amino acids that acts like a messenger, telling your cells what to do. “Amino acids, think of them as letters in the alphabet,” Mimi says. “When amino acids come together, they form a peptide, which is a word. Then when you have a lot of words together, you get a sentence or a protein.” So amino acids are the letters, peptides are the words, and proteins are the full sentences.

Your body naturally makes peptides already. In fact, some of the most familiar medications and hormones fall into the peptide category:

• Insulin
• Oxytocin (“the hormone that you release when you have an orgasm”)
• GLP-1 medications like semaglutide and tirzepatide

“Peptides are old medicine,” Mimi explains. They’ve been used off-label for decades, and bodybuilders were experimenting with them long before they hit TikTok. The catch is that with popularity came what she bluntly calls “grifters,” people promising one shot will give you “the tightest a** you’ve ever had.” Her take? “People who look at peptides like that are selling you a lie.”

Sourcing is the single most important thing

The peptide market is a legal gray area, which means a lot of what’s floating around online comes from sketchy places. Mimi’s rule is to only use a 503(a) pharmacy, the kind that gets inspected and does real testing. “These 503(a) pharmacies are being inspected…and you can ask, like is there third-party testing? Do you have certificates of authenticity?”

Anything labeled “research-use only” is a hard pass for her. And she’s seen the scams firsthand: “This morning I got an email from a pharmacy selling me peptides for basically something that normally costs $500 for $45.” She sent it to her uncle, a compounding pharmacist, who confirmed her suspicion. In other words, if a peptide deal sounds too good to be true, it probably is. 

Watch for these red flags

There’s no shortage of people willing to sell you peptides right now, but not all of them should be. Mimi’s tells for a sketchy provider are easy to spot. Run the other way if someone:

• Hands you a peptide without checking your labs first
• Doesn’t ask about your health basics (“how are you eating, sleeping, pooping?”)
• Recommends one random peptide just because it “gives you a glow”
• Promises it’ll fix everything

A responsible provider also screens your personal history first, especially around cancer, since some peptides stimulate growth and wouldn’t be appropriate for everyone.

Listen to the full episode on Glow Lab, available wherever you listen to podcasts.

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