Episode Details

A Note from James:

I’m doing a big experiment in my life.

I recently started taking a GLP-1—tirzepatide, one of the so-called weight-loss drugs. But I didn’t start taking it specifically for weight loss. I had some blood work done for the first time in a long time, and there was a small indication that I might be pre-diabetic. My doctor suggested trying tirzepatide, and I wanted to understand what I was getting into.

The first person I wanted to talk to was Charles Duhigg, author of The Power of Habit and Supercommunicators. Charles has been taking a GLP-1 for about two years, and he says it has changed his life. He has lost around 45 pounds, but what interested me most was not just the weight loss. It was the habit change.

Charles explains that GLP-1s can quiet what people now call “food noise”—the constant background pull toward eating even when you are not actually hungry. When that noise quiets down, something interesting happens: you get a window where your old habits become more malleable.

That is the key idea of this conversation. The drug may help you eat less, but the bigger opportunity is that it gives you a chance to build new routines around food, exercise, alcohol, sleep, and identity. And if you build those habits while the window is open, those habits may continue even after you stop taking the medication.

We talk about food noise, cravings, the habit loop, keystone habits, stated versus revealed preferences, placebo effects, alcohol, sleep, exercise, blood sugar, identity, and whether GLP-1s are a lifelong drug or a tool for changing who you become.

Episode Description:

James is at the beginning of a GLP-1 experiment. Charles Duhigg is two years in.

In this conversation, Charles explains what he has learned from taking tirzepatide and from studying GLP-1s through the lens of habit formation. He describes the first phase of public understanding around these medications as weight loss. Phase two, he argues, is about behavior change.

The central concept is “food noise.” Charles describes it as the background craving that turns a basket of fries into an almost automatic behavior. You may not even notice the noise until it goes away. Once it quiets, the cue that normally triggers the habit loop weakens. That creates a temporary window where new habits can be built.

James and Charles use the GLP-1 experience to revisit the basic habit loop: cue, routine, reward. They talk about why habits feel automatic, why willpower is often the wrong tool, and why successful behavior change depends on identifying the cue and replacing the routine while still satisfying the underlying reward.

Charles also introduces the idea of GLP-1s as a catalyst for keystone habits. Eating less can make exercise easier. Drinking less can improve sleep. Better sleep can improve focus. Focus can improve work. One changed habit can set off a chain reaction.

The conversation then becomes more philosophical: Who are we if one part of the brain says “I want to be healthy,” while another part of the brain keeps revealing different preferences through action? Charles explains the difference between stated preferences and revealed preferences, and how repeated behavior can shift identity.

This is not a conversation about taking GLP-1s casually. It is a conversation about using a medical intervention deliberately, under appropriate medical guidance, as a chance to change the patterns that shape daily life.

Editorial Note:

This episode discusses prescription medications, including tirzepatide and semaglutide, as well as personal experiences with GLP-1 drugs. It should not be treated as medical advice.

GLP-1 medications can have side effects and risks, including gastrointestinal symptoms, dosing concerns, and contraindications for some patients. They should be used