Before we talk about habits, we need to face the numbers.
The landmark STEP 4 trial (Semaglutibe Treatment Effect in People with obesity) provides the clearest picture. In this study, patients who lost weight on semaglutide were then randomly assigned to either continue the drug or switch to a placebo. The results were stark:
Time Point
Continued Semaglutide
Switched to Placebo
At randomization (after 20 weeks on drug)
-10.6% body weight
-10.6% body weight
48 weeks later
-7.9% additional loss (total -18.5%)
+6.9% regain (total -3.7%)
In plain English: patients who stopped the drug regained nearly two-thirds of their lost weight within one year. Their metabolic health markers—blood pressure, blood sugar, cholesterol—also trended back toward baseline.
Other studies have confirmed this pattern. A 2022 review found that one year after stopping GLP-1s, most patients regain 50-70% of the weight they lost. The food noise returns. The set point reasserts itself. The body's famine defense mechanisms kick back in.
This is not a failure of willpower. It is biology.
