Peptides are surging in popularity across wellness clinics, fitness circles and social media — but some physicians and former users are warning that the hype may be moving far faster than the science.
WATCH BELOW: 'We don't even know the whole effect of the side effects,' Dr. Mitchell Ghen tells WPTV's Kayla McDermott
Peptides — short chains of amino acids that act as building blocks for proteins — are being marketed for everything from weight loss and athletic recovery to better sleep, anti-aging and faster healing. But experts caution that many of these compounds remain poorly studied in humans, with potentially serious risks that consumers may not fully understand.
Dr. Mitchell "Mitch" Ghen, a Florida-based root cause functional physician who previously used peptides in practice, says he has become increasingly cautious about prescribing them.
"Without a strict and very comprehensive evaluation on a patient, I will not give a peptide myself," Ghen said.
Why peptides are gaining attention
The rise of injectable wellness treatments, including GLP-1 drugs like Ozempic, has helped fuel broader interest in peptides. Online influencers and "biohacking" communities frequently promote them as tools to optimize performance, accelerate healing or improve longevity.
But Ghen said many patients arrive with little understanding of what peptides actually are.
"They really don't know what they are," he said. "Only what they see."
Different peptides are designed to affect different systems in the body. Some are promoted for wound healing or gut repair, while others are marketed as metabolism boosters or performance enhancers.
Among the peptides currently drawing attention are:
- BPC-157, often promoted for healing and tissue repair
- TB-500, associated with recovery and wound healing
- MOTS-C, marketed for metabolism and mitochondrial function
- Growth hormone-related peptides such as ipamorelin and CJC-1295
The concern, Ghen said, is that the science behind many of these uses is still limited.
"We don't know enough because we don't," he said. "Most of it's from animal research."
Concerns about cancer and other side effects
One of Ghen's biggest concerns involves peptides that may increase VEGF, or vascular endothelial growth factor, a protein that helps form blood vessels. While VEGF can aid healing, it is also involved in cancer growth.
"Cancer often uses VEGF to grow," Ghen said. "Is it worth the chance without really knowing the biochemistry and functionality of that human? Not for me, not for my patients."
He says side effects linked to peptides can include headaches, nausea, vomiting and sleep disturbances, though the long-term impact remains unclear.
"We don't even know the whole effect of the side effects," he said.
Former peptide user Thomas Andrew said he learned that firsthand.
Andrew began using peptides several years ago after hearing they could improve athletic recovery and growth hormone output. At first, he said, the experience seemed positive.
"I definitely felt the edge on my recovery from it," he said.
But after restarting the same peptide combination years later through another provider, he experienced severe reactions almost immediately after injecting the drugs. He described intense flushing and debilitating headaches that worsened with each attempt, culminating in a migraine-level episode that lasted for days.
"He said, 'You're having a negative reaction to the polypeptide,'" Andrew recalled Ghen telling him. "'Tom, stop taking them.'"
Once he stopped, Andrew said the symptoms disappeared.
A booming trend with limited long-term data
Both Ghen and Andrew said the rapid growth of the peptide market concerns them because long-term human research remains limited.
Andrew believes many people are being drawn in by aggressive online marketing and promises of quick results.
"It's become bro science," he said. "Most people are looking for immediate benefit, whether it's weight loss or recovery, and they're not really looking over the horizon at what the long-term potential side effects are."
He said social media platforms, such as TikTok and Instagram, have amplified the trend, often presenting peptides as harmless wellness shortcuts.
"Sometimes trendy things aren't the best things," Andrew said.
FDA scrutiny and the compounding debate
The U.S. Food and Drug Administration has recently reviewed several peptides and recommended that 4 — BPC-157, KPV, TB-500 and MOTS-C — be considered for compounding, which allows specially licensed pharmacies to produce customized medications.
Some FDA scientists argued there is not enough evidence to support their use, while others supported allowing compounded versions so consumers would be less likely to buy unregulated products online.
Ghen said he understands both sides.
"I agree with the FDA panel scientists that said we don't know enough," he said. "But I would rather someone take a polypeptide from a registered compounded pharmacist as opposed to taking it from off the internet."
Still, he says major concerns remain about product consistency, sourcing and sterility.
"There could be some serious side effects associated with it," he said.
Andrew is more critical of the FDA's direction, arguing the products are reaching consumers before adequate testing is complete.
"There aren't any long-term human trials," he said. "We have to study them. We have to understand them."
The importance of testing and medical oversight
Ghen stresses that peptides should never be treated as standalone solutions or casually prescribed based on trends.
"They are not a standalone treatment," he said. "They're a cog in the wheel."
He criticizes high-volume clinics where patients can request peptides without extensive evaluations.
"It's like picking up a milkshake," he said. "It doesn't work that way."
Instead, Ghen said patients should undergo comprehensive testing before considering peptide therapy, including hormone panels, inflammatory markers, metabolic testing and, in some cases, mitochondrial or autonomic nervous system evaluations. He argues that physicians should first determine whether a patient actually has the deficiency or dysfunction the peptide is intended to address.
Andrew said he later discovered the peptide treatment he used to increase growth hormone levels may never have been necessary.
"My growth hormone output was in the perfect middle reference range," he said. "I didn't need more."
His advice to others is simple: do not take peptides without understanding whether your body actually needs them.
Online products raise additional concerns
Both men strongly warn against buying peptides online, especially products labeled "for laboratory use only."
"Absolutely avoid them," Ghen said. "If you don't know where it's coming from, just because it's cheaper doesn't make sense."
Unregulated products may vary widely in purity, dosage and sterility, he said.
"You would never go into a pharmacy without an oncologist and say, 'Give me that cancer medicine,'" Ghen said. "That's how ridiculous it is to pick out a polypeptide and say, 'I'm going to take that one.'"
A cautious message amid the hype
Neither Ghen nor Andrew dismisses peptides entirely. Both acknowledge they may eventually prove beneficial for some patients in certain medical settings. But they said the current enthusiasm has outpaced the evidence.
For people considering peptides, they recommend working with experienced healthcare professionals, getting thorough testing first and carefully weighing potential risks against possible benefits.
"Be very, very, very cautious," Andrew said. "It's a trendy thing."
This story was reported on-air by a journalist and has been converted to this platform with the assistance of AI. Our editorial team verifies all reporting on all platforms for fairness and accuracy.
