Tirzepatide and Semaglutide will not solve the worldwide obesity epidemic, but are a good start nonetheless

From Integrity Talk: We’re on the Verge of Reversing Obesity.

The good news is Tirzepatide and Semaglutide are the most effective non-surgical weight loss treatments on the market. The bad news is this is a low bar. I think it’s premature and unsupported by the evidence to say we’re on the verge of reversing obesity. As I wrote here, these drugs despite being highly effective are insufficient alone to reverse the obesity epidemic in in the US or worldwide.

He writes:

A growing number of studies report promising results, with a mean 15% loss of body weight after only 68 weeks. Some participants in the studies reported mild side effects such as nausea or diarrhea, but for the most part, these were transient and resolved quickly. If you’re wondering what these numbers mean, 10–15% loss of body weight is basically considered the “holy grail” in obesity treatments.

But only a 15% average reduction still means a lot of obese or borderline-obese/overweight people, but just not as many as before. For example, a 250lbs 5’9″ male who loses 15% to 212lbs still has a BMI of 31.3, which is class 1 obesity compared to class 2 obesity before.

Worse still, someone who is still obese or borderline obese on these drugs may deicide it’s not worth the monthly cost and side effects to continue. Consequently, the weight and old eating habits return. Half of people on Wegovy stop taking the drug after a year, and for most people the weight returns.

If every obese American went on Tirzepatide, which is even more effective than Semaglutide–and ignoring costs and assuming 100% patient compliance–my back-of-envelope calculation shows that up to only a third of obese people can be cured. A quarter to a fifth of people on Semaglutide respond well, so these obese people will lose enough weight to no longer be obese, even for class 3 obesity. Those who respond average/typical who are class 1 obese may be become only overweight. So this leaves the other 2/3 of obese people who are either too obese or do not respond well enough, or must discontinue the drugs due to side effects.

Despite the popularity of these drugs, it’s not yet possible to predict how much weight someone will lose. Some headlines suggest a history of diabetes or childhood obesity portends to less weight loss. But the viral stories on social media of people who lose substantial weight (in excess of 25-30 percent of starting bodyweight) and go from being obese to slim are likely outliers. It’s reasonable to assume that social media success stories will be outliers compared to the average, as individuals who lose less weight may be less inclined to post about it.

This is why I predicted that these drug would not hurt food sales, such as for retailers like Walmart, despite initial concerns last year. Except for the minority of users who respond very well, many of these people who are on GLP-1 drugs now and are still overweight will be off them in a year or so, deciding it’s not worth it.

Indeed, it looks like I was right again, as Walmart stock has rocketed to new highs as such fears have come to pass:

Helping the other two-thirds of the population will take additional drugs or new approaches that target the metabolism or the part of the brain that regulates weight, assuming this exists, instead of only gastric emptying. An experimental triple-action peptide Retatrutide boosts metabolism, and produces even greater weight loss compared to Semaglutide or Tirzepatide. Or gene therapy, perhaps. A multi-modal approach may finally make obesity a thing of the past, but this won’t be for a long time.