GLP-1 Medications Changed the Conversation About Weight. Here Is What Still Determines Whether It Lasts.

For nearly twenty years of general practice, I watched capable, disciplined people try to lose weight through willpower alone, and I watched most of them regain what they lost, not because they lacked discipline, but because we were asking willpower to override biology. The arrival of GLP-1 medications is one of the most significant developments in weight and metabolic medicine of my career, and it deserves to be treated as exactly that: a genuine breakthrough, not a shortcut.

What are GLP-1 medications, and why is the excitement justified?

GLP-1 is a hormone your gut already produces after eating. It signals to your brain that you are full, slows down how quickly your stomach empties, and helps regulate blood sugar. Medications like semaglutide and tirzepatide work by mimicking that hormone at a much stronger, more sustained level than your body produces on its own.

The results in trials have been substantial. In the STEP 1 trial, adults taking semaglutide lost an average of around 15% of their body weight over 68 weeks, far beyond what lifestyle intervention alone typically achieves. Tirzepatide, tested in the SURMOUNT-1 trial, produced even greater average losses. Perhaps most significantly, the SELECT trial found that semaglutide reduced the risk of major cardiovascular events by 20% in people with overweight or obesity and existing cardiovascular disease, even those without diabetes. That is not a cosmetic result. That is a medication changing hard clinical outcomes.

There is also something quietly important happening in how we talk about weight. For a long time, obesity was treated as a failure of character. GLP-1 medications, and the biology behind them, make it much harder to keep telling that story. Appetite and weight regulation are governed by hormones and brain circuits, not moral fibre, and a treatment that works by correcting a hormonal signal is powerful evidence of that.

So why isn’t the medication the whole story?

Here is the part I want to add, not as a caveat, but as the piece that helps people keep what they have gained. Many patients describe the effect of these medications as the “food noise” finally going quiet, the constant background hum of thinking about food, resisting food, negotiating with food, simply switches off. That is a remarkable physiological gift. It is not, on its own, a new relationship with food, movement, sleep or stress. Those are learned patterns, often built up over decades, and quieting the appetite signal does not automatically rewrite them.

This matters practically in a few specific ways. Trial data shows that a meaningful portion of the weight lost on these medications is lean muscle, not just fat, which is why resistance training and adequate protein intake matter alongside the medication, not as an afterthought. Appetite suppression can also reduce overall food intake enough to affect micronutrient status, which is worth monitoring rather than assuming. And when medication is eventually reduced or stopped, appetite tends to return towards baseline, so the habits built during treatment are what carry a patient through that transition, not the prescription alone.

What about the metabolic and hormonal picture underneath?

Behaviour change is only one half of what determines whether this lasts. The other half is making sure the metabolic and hormonal picture underneath is actually being addressed, not simply masked by an appetite signal that has been turned down. For some patients, weight gain and metabolic dysfunction were driven, at least in part, by something identifiable: insulin resistance, an underactive thyroid, or the hormonal shifts of perimenopause and menopause that quietly change how the body stores fat and responds to food.

A GLP-1 medication does not correct any of that on its own. It changes appetite and satiety signalling, which is powerful, but it is acting on a downstream effect, not necessarily the upstream driver. This is why, alongside the behavioural work, I want to know what a patient’s fuller metabolic and hormonal picture actually looks like: insulin and blood sugar regulation, thyroid function, and where relevant, oestrogen, progesterone and testosterone. If any of that needs mending, and for many midlife patients some of it does, treating it directly gives both the medication and the behaviour change work a healthier foundation to build on, rather than asking appetite suppression to compensate for an imbalance it was never designed to fix.

What actually makes the result last?

This is where my own training outside pure clinical medicine has been genuinely useful. I spent years studying medical anthropology, looking at why people do or do not change behaviour even when they know exactly what is good for them, and I have trained formally as a health coach. The honest answer is that sustainable change is rarely about information. Most patients already know that vegetables are good for them. It is about identity, habit and support, built deliberately, at the same time the biology is being corrected, not afterwards.

The patients who do best on these medications are not the ones who treat them as a solution to be left alone to work. They are the ones who use the window the medication opens, appetite quiet, cravings reduced, energy more available, to actually build the strength training habit, the sleep routine, the way of relating to food that will still be there once the prescription changes. The medication does the metabolic work. The behaviour change work is still yours to do, and it is considerably easier to do it now than it ever was before.

What this means at The Schoeman Clinic

This is why, where GLP-1 treatment is appropriate for a patient, we treat it as one part of a properly assessed, whole-person plan: nutrition, strength training and sleep, any underlying metabolic or hormonal drivers identified and treated on their own merits, and the behavioural support that determines whether a result lasts for years rather than months. If you want to understand whether this approach is right for you, a proper assessment is the place to start, not a prescription in isolation.

If this resonates, get in touch to find out what a comprehensive, whole-person approach to metabolic health could look like for you.

References

• Wilding JPH, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. New England Journal of Medicine, 2021 (STEP 1 trial).
• Jastreboff AM, et al. Tirzepatide Once Weekly for the Treatment of Obesity. New England Journal of Medicine, 2022 (SURMOUNT-1 trial).
• Lincoff AM, et al. Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes. New England Journal of Medicine, 2023 (SELECT trial).