Why Is Everyone Talking About GLP-1s?

You can’t scroll, click, or talk to anyone looking to lose weight without hearing about GLP-1s or GIPs lately. These medications are everywhere.

But what are they really, and how do they actually work?

Semaglutide vs. Tirzepatide: What’s the Difference?

Semaglutide (Wegovy, Ozempic) mimics a natural hormone (GLP-1 or glucagon-like peptide-1) that helps regulate hunger and blood sugar.

Tirzepatide (Mounjaro) targets GLP-1 and another hormone called GIP (glucose-dependent insulinotropic polypeptide), which also affects hunger and insulin response.

These medications were first created for people with diabetes, but doctors now also prescribe them to support weight loss for people without diabetes who meet certain criteria, like having a higher BMI or weight-related health risks.

They do a great job of quieting cravings and lowering how much you eat, but that can quickly backfire if you’re not paying attention to nutrition.

What Happens When You’re On GLP-1s?

Here’s what typically plays out:

• Appetite drops – eating less – weight goes down.
• Less food – less protein (and nutrients) – muscle starts to drop, too.
• Under-eating – less fuel – metabolism slows.
• Less structure – your body gets smaller, but also weaker.

Simply put: eating less is easy. Eating right takes more intention.

Can Food Boost GLP-1 Naturally?

Technically, yes, for a few minutes. Realistically, no, not enough to matter.

Certain foods can raise GLP-1 levels a little because when you eat, your body releases a small amount, but it only lasts a few minutes.

Prescription GLP-1 drugs raise those levels much higher, and keep them there anywhere from a few hours to a few days.  

So, while food helps a little, it’s nowhere near enough to create the same appetite control or impact as prescription GLP-1 drugs.

Still, paying attention and eating nutritious, balanced meals while using GLP-1s is important because your appetite won’t remind you. That’s kind of the whole point of the medication.

Do These Medications Cause Muscle Loss?

Not directly. But here’s the issue:

When you eat too little (especially protein), your body will pull energy from muscle. Ideally, energy should mostly come from carbs and fats, not your muscle tissue.

This is a well-known and common issue in very low-calorie diets, and it applies here, too¹.

Research shows that the best way to protect muscle during weight loss is to combine strength training with hitting your protein targets daily².

Are GLP-1s Enough on Their Own?

Honestly, no.

Yes, they reduce weight, but studies show they also speed up muscle loss.

In fact, users lost over 10% of their muscle mass in the first year. That’s the same amount you’d expect to lose naturally in about 20 years of aging. That’s a lot, really fast.

It’s important to note that muscle isn’t just about looking toned. It helps you move, balance, stay strong, and keep your metabolism healthy. Losing too much (especially that fast) can leave you feeling weaker and tired instead of strong and energized. That’s not the goal, and it’s not healthy either.  

Bone Health Also Takes a Hit

Losing weight means your bones aren’t carrying as much load day-to-day. That might sound like a good thing, but bones actually need regular stress (called loading) to stay strong.

When that load drops, and especially if you’re not strength training, bones can slowly weaken over time. You won’t feel it right away, but it happens quietly in the background.

That’s why lifting weights really isn’t optional during weight loss. Strength training gives your bones the pressure and challenge they still need to stay strong and healthy.

The Smarter Plan: Medication Plus Habits

Medications help with weight loss. But they don’t teach habits. And without habits, results rarely stick. Here’s what a solid approach looks like:

• Accountability and support – so you stay consistent and solve problems early.
• Smart nutrition – even when your appetite is low, your muscles still need fuel.
• Meal consistency – regular eating helps avoid under-fueling (major issue with these drugs – I know, you go from “always hungry” to setting reminders to eat).
• Strength training 2–3x a week – to protect muscle and bone health.
• Self-awareness – so you can spot issues and adjust before they spiral.
• Planning for life after meds – because the habits you build now matter later, especially if you decide to stop or can’t continue them for any reason.

GLP-1s make weight loss easier, but they don’t make it automatic or permanent. Obesity is considered a chronic, lifelong condition, and managing it takes thoughtful, strategic, ongoing care, just like any other long-term health condition.

Bottom Line: This Is About More Than Just Getting Smaller

GLP-1s help lower weight. But they don’t:

• Build or protect muscle.
• Improve your movement.
• Create lifelong habits.

Without those pieces, you can lose weight and still feel weak, unstable, or unhealthy.

The goal shouldn’t just be losing weight; it should be to lose weight while staying (or becoming) stronger, steadier, and healthier, long after the prescription ends.

Quick Myth-Busting (Because You’ll Hear These Everywhere)

“GLP-1s are a cheat code.”
They help (like any other tool), but they don’t replace habits. You still need structure.

“I’m not hungry, so eating isn’t important.”
Not true. Lack of hunger doesn’t mean your muscles stop needing fuel.

“I’ll get serious about fitness later.”
Big mistake. Because when is later? Later will be too late. Strength training matters now.

“If I regain when I stop, the meds didn’t work.”
Some weight gain is possible. But a significant amount of regain usually means that habits weren’t solid. This is fixable, and why preparation matters.

The takeaway is: Use GLP-1s as the tool to help you create smart habits. That’s really the best way to ensure long-term success.

---

Resources

1. The impact and utility of very low-calorie diets: the role of exercise and protein in preserving skeletal muscle mass https://journals.lww.com/co-clinicalnutrition/fulltext/2023/11000/the_impact_and_utility_of_very_low_calorie_diets_.6.aspx ↩︎
2. Mechanick JI, Butsch WS, Christensen SM, Hamdy O, Li Z, Prado CM, Heymsfield SB. Strategies for minimizing muscle loss during use of incretin-mimetic drugs for treatment of obesity. Obes Rev. 2025 Jan;26(1):e13841. doi: 10.1111/obr.13841. Epub 2024 Sep 19. PMID: 39295512; PMCID: PMC11611443. https://pubmed.ncbi.nlm.nih.gov/39295512/ ↩︎

Photo Credits

Measuring Tape by rattanakun

Cooking by LightFieldStudios from Getty Images Pro