Click here to join The New Weight-Loss Reality special event.

A while back, I talked with two people who were doing beautifully on GLP-1 medications. They’d lost weight, felt great, and considered the medications lifesaving. But six months later, both told me something I didn’t expect: they wanted to wean off. That got me thinking about some important aspects of these medications that don’t get discussed nearly enough.

1. GLP-1 Isn’t Your Body’s Weight-Regulation Hormone

GLP-1 is a hormone your body naturally releases very briefly at the end of a meal, to signal that you’re full and it’s time to stop eating. The medications create a nonstop GLP-1 signal, exposing receptors throughout the brain and body to continuous, high levels they’re simply not used to.

But GLP-1 isn’t actually the hormone whose job it is to regulate body weight. That’s leptin. Leptin resistance can develop when high triglycerides, elevated insulin, and inflammation interfere with the brain’s ability to receive leptin’s “we have enough stored energy” signal. Because those conditions are strongly tied to a diet high in ultra-processed foods, sugar, and flour, simply eating less on a GLP-1 may not be the whole answer. Food quality still matters if you want the brain and body’s own weight-regulation systems to work better.

2. GLP-1s Affect Both Appetite and Dopamine

These medications work on more than hunger. They also affect dopamine signaling in the mesolimbic reward pathway, including the nucleus accumbens. That can quiet food noise and reduce cravings for food, alcohol, nicotine, and other rewarding behaviors.

But people who already have dopamine downregulation from addictive behaviors may experience anhedonia, which is a flattening of pleasure, motivation, and interest, when dopamine spikes are further blunted.

3. They May Change What You Want to Eat

GLP-1 medications can suppress appetite so strongly that healthier foods may become less appealing. They can create a compensation effect: “I’ve barely eaten today, so a few M&Ms are fine.”

That matters because muscle loss, hair loss, and other problems may not come directly from the medication itself, but from eating too little and from the kinds of calories people choose when appetite is so reduced.

4. Emotional Stress Can Override the Medication

When life is calm, a GLP-1 may seem almost miraculous. But during an intense emotional event, the amygdala can trigger a strong stress response, cortisol rises, and the prefrontal cortex becomes less effective at regulating behavior. Some people then find themselves bingeing right through the medication.

That tells me a GLP-1 may not be enough as a stand-alone long-term solution. We still need tools for handling emotion, stress, and the behaviors that food may have been regulating.

5. The Effects Go Far Beyond Appetite

GLP-1 receptors exist throughout the brain and body, including areas involved in the autonomic nervous system. These medications can increase heart rate and decrease heart rate variability, reflecting effects on sympathetic (fight or flight) and parasympathetic (rest and digest) activity.

They also directly dampen signaling through the vagus nerve, the two-way communication pathway connecting the brain with the heart, lungs, gut, and other organs. This decreases the “gut feelings” that are communicated from the gut to the brain. This is why some people describe feeling less connected to bodily signals or intuition while taking them.

The Missing Piece in GLP-1 Research

We’re also missing an important piece of research: studies generally aren’t separating people according to food-addiction susceptibility. We know GLP-1s can reduce food noise, but we don’t yet know enough about what happens to that noise, body dissatisfaction, and addictive patterns when people eventually stop taking them.

We’re living in a new weight-loss reality. GLP-1 medications may be enormously helpful for some people, but they’re only one part of a much bigger picture. If you want to understand how they fit into long-term weight loss—and what your options are whether you use them, avoid them, or eventually want to come off them—join me for my New Weight-Loss Reality event. I’ll be sharing the latest research, answering questions live, and helping you think through what the new landscape means for you. The link to register is below.

Click here to join The New Weight-Loss Reality special event.