Day: July 26, 2025

• Peptide injections are soaring in popularity for fitness and longevity.
• They’re marketed as a “natural” supplement for muscle-building, fat loss, recovery, and more.
• The FDA has been cracking down on peptide sellers, and experts say some caution is warranted.

People who want to feel younger, look fitter, or perhaps slough off a little layer of belly fat have been turning to an increasingly popular kind of treatment — one you can get without a prescription.

They’ve got obscure names like BPC-157, tesamorelin, and cerebrolysin. All it takes is a tiny needle and a little clear vial filled with injectable molecules.

Welcome to the world of peptides.

“Absolutely everybody’s asking for it, the field is popping,” Dr. Florence Comite, a longevity doctor who serves concierge medicine clients in New York City, told Business Insider.

The peptide landscape is so large that it almost defies definition. The prescription drugs Ozempic and Mounjaro, often used for weight loss, are peptides. So is insulin. There are peptides in skin creams, hair products, and high-end serums marketed to women to reduce fine lines and stimulate collagen. The wildly popular fitness supplement creatine? Also a peptide.

Then, there are the gym bro shots, said to boost muscle, burn fat, stimulate testosterone, and aid recovery.

Demand for peptide injections — something that biohackers and longevity-seekers have already been quietly using in the shadows for decades — is booming. Patients in pockets of the country saturated with peptides, like Beverly Hills, San Diego, Silicon Valley, and Manhattan are increasingly asking their doctors: “should I try peptides?”

Many physicians aren’t sure what to say because there isn’t a ton of great evidence around about how much peptides can really do. Plus, the FDA has been cracking down on peptide compounders in recent years. They worry that the hype is outpacing good evidence.

How peptides boost your body

Unlike most pills that doctors prescribe, peptides live in a more slippery area, between drug and bodily substance.

A peptide is a chain of organic compounds — specifically, amino acids — that stimulate natural processes. Depending on which amino acids a peptide is made of, and how it is used, the molecule can have all kinds of impacts on how our hormones operate. Peptides can improve fertility in both men and women, tamp down inflammation, remove dangerous visceral belly fat, or help build muscle. Others are thought to help improve sleep quality, even possibly improve brain health.

“What’s great about peptides is that they mimic the body,” said Comite, who has been working with peptides since she was a research fellow at the National Institutes of Health over 30 years ago.

Since most peptides are too fragile to be formulated as pills, they are often packaged as a clear liquid in a little vial. Users learn to inject their peptides using a very fine, short needle, right at home.

The popularity of peptides has soared on their reputation as ostensibly “natural” products. The idea being that, unlike other drugs or steroids, peptides are a safer choice because they’re just stimulating your body to do its own thing.

Taking growth hormones, for example, comes with a suite of undesirable potential side effects, like an increased risk of cancer and type 2 diabetes. What if you could just take a peptide that would stimulate your own growth hormone to make you stronger, leaner, and more energetic?

“The theory is that even if you use a growth hormone stimulating peptide, your body’s only going to be able to make so much growth hormone,” Dr. Sajad Zalzala, a longevity physician and one of the cofounders of AgelessRx, said. “Kind of like a check valve already in place. Again, that’s the theory.”

The peptides gym bros take to get chiseled muscles

One darling peptide of gym bros and longevity fiends alike is a substance called BPC-157. It’s known as the “Wolverine” shot for its perceived ability to heal you up and regenerate your body real fast like the Marvel character, Logan, after a big fight.

B-P-C stands for “body protection compound.” BPC-157 was first derived from stomach juices. It’s being investigated to treat inflammatory bowel diseases, including Crohn’s and ulcerative colitis. But the reason that athletes like it is because it’s thought to reduce inflammation and improve blood flow — and perhaps do even more.

There are a few other super popular peptides:

Tesamorelin, an injectable peptide, is prescribed to HIV patients to reduce excess belly fat. Sermorelin is supposed to help with sleep and recovery. CJC-1295 binds to growth hormone receptors in the body, and people often take it alongside impamorelin, which stimulates the hypothalamus. The two in tandem are said to deliver better muscle gains.

On Reddit and YouTube people share how they “stack” different peptides like this, taking multiple different kinds with the goal of boosting the effects of each.

One snag: The FDA is making peptides harder to access

Peptide fans get their shots at clinics and med spas — or, for less money, online.

Increasingly, people are ordering peptides that are labeled “for research only,” meaning they are supposed to be used by lab workers for experimentation, and were never meant to be put into human bodies.

That’s partly because the FDA crackdown on peptides has intensified in recent years, just as pharmaceutical compounding (a sort of acceptable way to get knock off medications) has surged in popularity, with people seeking cheaper versions of GLP-1 drugs like Ozempic and Mounjaro. At the beginning of 2022, the FDA had a list of four peptides that they said “may present significant safety risks” and should not be compounded. By the end of 2023, there were 26.

Comite thinks the FDA crackdown is a shame. She is finding it harder and harder to source compounded liquid BPC-157. She often uses a patch form of BPC-157 on herself, placing it over sore areas or injuries. Recently, she tore a calf muscle, so she’s been using it there, but she also just likes how taking a little bit of it keeps her active and moving.

“I use it almost every day,” she said. “It’s amazing for joints and everything — at a very tiny dose.”

Zalzala, who doesn’t usually prescribe peptides, ordered some topical BPC-157 recently when his wife had a knee injury. “My wife says it works,” he said, though he cautioned that it’s hard to really know if that’s true without more proper research.

Bracken Darrell, the CEO of VF Corporation and one of Comite’s patients, is also a BPC-157 convert. A self-proclaimed “basketball nut,” he’s on the court about three days a week. On the days when he doesn’t pick up a ball, he’s out cross-training on a bike or lifting weights.

So when he tore his meniscus about four months ago, he was worried. Under Comite’s supervision, he started taking liquid BPC-157 about three to four times a week.

He told BI it was “weird” at first, learning to inject the needle into an area of skin near his knee. But, pretty soon, it was just part of his routine.

“I believe it helped a lot, but it’s hard to know for sure,” he said. “There are people with a severely torn meniscus who don’t ever play basketball again, and I’m back — I certainly wouldn’t conclude that’s because I’m taking BPC-157, but at a minimum it didn’t hurt. And it sure seems like it helps.”

Proceed with caution, doctors say

Even longevity doctors who prescribe and use peptides regularly agree that some folks are overdoing it, and that could be dangerous.

“Proceed with caution, because you have to know the source and you have to know it’s active,” Comite said. “It’s not like Lowe’s or Home Depot where you can get stuff and you can fix the plumbing.”

In reality, the evidence for peptides is still murky. There are no big, randomized clinical trials like what we have for prescription drugs or vaccines. The current hype is based on anecdotal evidence, a few small human studies from decades ago, and rodent studies.

“People wanna take the peptides because they’re not from big pharma, they’re not mainstream medicine, they gotta be better than those cockamamie doctors,” Dr. Eric Topol, a cardiologist and longevity expert, said recently on the Dax Shepard podcast. “Where’s the data?”

For people who are using peptides, experts shared two pieces of advice:

Comite urges patients to start slow. A common mistake people who are dosing themselves make is thinking that “if a little bit is good, then a lot must be better,” she said. That’s not the case.

“Taking mega doses of tesmorelin along with testosterone causes your organs to overgrow,” Comite said. Sometimes she’ll see a toned gymgoer with a potbelly, and wonder whether that’s due to an enlarged liver or spleen.

Darrell recommends testing your peptides with an independent lab so you know what you’re getting is both real and uncontaminated.

Zalzala says his company started thinking about offering peptides a few years back, due to consumer demand, but they haven’t yet. There are just so many peptides out there, and it’s hard to tell which might be the very best.

Some of the most research-backed ways to have an impact on your longevity and fitness are still the simplest anyway: eat decent amounts of fiber and protein regularly, work out — at least a couple sessions with weights each week, and cut back (or ideally, eliminate) liquid sugar in your diet like juice and soda.

• Jennifer Donnelly is a Dallas-based matchmaker who’s set up hundreds of couples.
• She works with ultra-high net worth individuals, charging rates from $150,000 to $500,000.
• Part of the job, she says, is pushing back when what a client wants isn’t what they need.

This as-told-to essay is based on a conversation with Jennifer Donnelly, a Dallas-based matchmaker for wealthy individuals. It’s been edited for length and clarity.

I work with some of the world’s most influential people to help them find that compatible partner. My sorority sister is married through me, and the person who lived across the street from me when I was eight years old is married through me. It’s such a rewarding career.

Out of college, I worked for a company that matched people for dating. It was a really high volume of people, like thousands, at a lower price point, and we were only matching people inside that service.

But I wanted to be able to meet the client, get to know them, and search all over for the right fit. So I said, if I do this again, it should be for fewer clients at a higher price point to deliver exceptional results.

I’ve been matchmaking specifically for wealthier clients for the past 10 years. Usually, around 30 to 40% of my month is spent traveling for work. I’m able to go search and hop on a plane to meet with a candidate and screen them. I can do things now that I never was able to do in the previous company.

My network and reputation built my clientele. One of my first clients was a well-known billionaire, and then he started referring other people directly to me.

My clients have incredibly high expectations, but I do too. My clients often say, “Jennifer, I think you might be even more selective than I am.”

For clients, my rates are for a 1-year period. They start at $150,000, which is generally for a search within a certain city. Then $250,000 is typically for a whole state, and at $500,000, we do a nationwide search. We gauge the rate based on the market and size. The candidates never pay.

When I initially meet a prospective client, we go through at least two interviews, if not three. My clients are understandably very private, so I have to get them comfortable being vulnerable because I can only be as good as they allow me to be. I’ll be a lot more effective the more information I have.

Often, wealthy men are used to people telling them what they want to hear. I don’t do that. This is about being effective and having a successful outcome. And oftentimes that requires a level of honesty that somebody hasn’t presented to them before.

Sometimes what people want and what they need is different. “Well, I want her to have an incredible career, to be a great mom, to be able to travel at a moment’s notice because I’ve got a plane.” And how can all of those things fit? Let’s talk about what really matters in the relationship.

When we start, I explain it might take up to six weeks. But if we’re at six weeks, and I have not found the person, I’m not going to just put somebody in front of them. I’ll just keep looking.

We create strategy plans for each client. We create a profile of what we envision for that client, and then we’ll say, “Okay, how are we going to find people like this?” and then we’ll start working through our network.

The good thing is we’re incredibly well-connected. It would be highly unusual if there was a candidate we wanted that I couldn’t get through somebody I know.

It’s important that they truly want a relationship. I always ask candidates, “Are you dating anybody? Does anybody think they’re dating you? You could end up married; are you ready for that?” There’s other matchmakers that can create dates. I’m really trying to create relationships.

We’ll conduct sometimes over 100 interviews before a client goes on one date. We want to make sure this isn’t a waste of time for the client or the candidate; we would like to think we’re matching for both people.

As far as dates go, it can be as simple as dinner to something much more elaborate. The client can decide if they’d like to help plan it, or leave it to us or have their assistants plan it.

I love attending the weddings of couples I’ve matched. That’s the prize for me. It’s like, OK, I did it, this is why I’m in this profession.

But oftentimes the couple will tell me at their wedding, “Hey, please don’t mention you’re a matchmaker. Just say you’re a ‘consultant.'”

• I joined an AI training session for KPMG interns at the firm’s training center in Florida.
• The Big Four firm recommended their interns try out five prompting techniques.
• The session showed me that learning to use AI is more about using language well than tech skills.

On a sweaty Monday morning in June, I joined 90 KPMG tax interns in an air-conditioned classroom in Florida.

We were there for one reason: to learn how to use AI.

We gathered at Lakehouse, KPMG’s gleaming training facility in Lake Nona, Florida. I had been invited to spend two days at the facility as part of my ongoing reporting about AI and the consulting industry, and as the class had already started, I slipped in quietly and took a seat.

Given that KPMG helps some of the world’s biggest companies figure out how to use AI, I was curious to see how the consulting giant was teaching its own employees to use the technology.

My biggest takeaway? Upskilling for the AI era can be surprisingly basic.

The five ways of asking AI a question

Four large screens — two on each wall— hung down from the ceiling in the classroom, and the 90 interns sat around circular tables in groups of six.

Sherry Magee, a senior director at KPMG, told me during a tour of the property that the space was designed so there was no “front row of the classroom,” which she said encourages participation.

The training session was run by two KPMG employees. They opened with a question about the interns’ use of AI: “Who just generally goes straight to it and just starts typing?”

Pretty much everyone in the room raised a hand.

One of the instructors explained that instead of chatting with AI, there were five prompting techniques they could use to adjust the model’s response to get the “best, most relevant, and accurate output.”

The techniques are:

1. Chunking: dividing a large prompt into smaller, more manageable requests
2. Few-shot prompting: giving the AI a few examples to guide its response
3. Iterative question refinement: repeatedly rephrasing or refining your questions to lead the AI to a more precise response
4. Chain of thought prompting: asking AI to include a breakdown of how it has reached an answer
5. Flipped interaction prompting: requesting that the AI ask you questions to prompt new thoughts

They work best for different tasks, the instructors explained. For example, a “chain of thought” prompt can be useful to get AI to show its work. This “thinking aloud” approach is more transparent and can be useful for tax professionals who need to check the results for inaccuracies.

“Flipped interaction” prompts could be used in a tax setting to prepare a client profile or to tailor advice.

The instructor told the interns that asking AI to prompt them with questions can be helpful for “making you think of things you don’t often think of yourself.”

Echoes from my journalism degree

The two-hour training session covered the foundations of KPMG’s AI tool for tax, the Digital Gateway. It also explained the concept of AI personas, introduced techniques to reduce hallucinations, and taught the interns KPMG’s key ethical principles to apply when using AI.

The interns were also taught how to provide AI tools with the right detail and tone for their target audience.

I’m no tax expert, but I am a journalist — and what struck me during the session is how much these teachings echoed the ones I was taught in journalism school. The success of an interview hinges on the quality of the questions I ask the other person. As KPMG stressed in its training sessions, by thinking about how you communicate information to an AI, you can also get the most helpful outcome from said AI.

“The more detail you give it, the more likely it is to predict the next thing correctly,” explained the instructor.

The intern training focused on admin-related examples of using AI, like drafting emails or creating slide decks. It wasn’t the most complicated or advanced stuff, but the session I attended was for summer interns in the tax division, so I wasn’t seeing how the firm’s leading technicians tackle AI.

More senior employees are using AI for industry research and preliminary audit memos, Becky Sproul, a KPMG audit partner, told me during an interview later that day.

They’re presenting AI with client documentation, auditing, and accounting standards, and asking it to write “a memo going through all the various attributes of the accounting standard,” she said.

That preliminary work can help get tax professionals “80% of the way there,” Sproul said.

The firm is also building AI agents where the “agent almost becomes like a team member,” and is using engagement metrics to encourage employees to use AI, she said.

The other Big Four firms — Deloitte, EY, and PwC — have also deployed agentic AI platforms this year, which they all present as being transformative for the workforce and productivity.

Teaching methods

The simple teaching methods used in the session were another reminder that while AI is complicated, learning how to use it doesn’t have to be.

The interns were learning about technology that is transforming workplaces, but they were still using large cardboard flipboards to share their ideas.

The session had one extra reminder for workers in the AI age: Take a break from your screen.

At one point, an employee from the Lakehouse’s “stretch” team, its on-site gym, ran into the center of the room and announced he was there to lead them through a “wellness break,” which entailed five minutes of stretching and breathwork accompanied by relaxing music.

The interns stood up with bemused expressions, but soon the whole class was loosening up, which the instructor told them would help them stay focused.

“This is what we signed up for, right?” I heard one intern joke as he lunged forward.

Choosing to prioritize my reporting over a relaxing stretch, I didn’t join in.

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