STAT+: Genetics may shape GLP-1 outcomes, slightly

23andMe published a study in Nature analyzing genetic data from 27,885 people who took GLP-1 medications. The headline finding: a variant in the GLP1R gene is associated with 1.7 to 3.3 extra pounds of weight loss per copy. A separate variant in GIPR predicts higher nausea risk specifically on tirzepatide (Zepbound, Mounjaro), but not semaglutide (Wegovy, Ozempic).

The numbers are real but small. An extra 1.7 to 3.3 pounds on top of average weight loss of 15 to 27 pounds is a rounding error for most people. And the study confirms what patients already experience firsthand: weight loss on GLP-1 drugs ranges from 5% to 20% of body weight, and nausea rates swing from 5% to 78% depending on the person and the medication. Genetics explain some of that variation, but not most of it.

So here’s the question you’re probably asking: should you pay for 23andMe’s new “GLP-1 Medications” genetic report? The report is part of their Total Health membership at $299/year. It tells you whether you carry the GLP1R or GIPR variants and gives you a sense of how you might respond. On paper that sounds useful. In practice, the information is unlikely to change what you or your doctor actually do. If you’re considering a GLP-1, your provider will start you on the lowest dose regardless of your genetics and titrate up based on how you respond. If you get bad nausea on tirzepatide, you’d switch to semaglutide whether or not a gene test predicted it.

The more interesting finding for consumers is the GIPR/nausea connection. If you’re choosing between semaglutide and tirzepatide, knowing you carry a GIPR variant associated with higher nausea could tilt that decision. But most providers already manage nausea through dose titration and anti-nausea medication rather than genetic screening. Bottom line: the science is legitimate, the consumer product is premature. Save your $299 and spend it on the actual medication. Providers like Ro and Noom Med will help you figure out which GLP-1 works for your body through the old-fashioned method of trying it.

Source: STAT News

Frequently asked questions

Is the 23andMe GLP-1 report worth $299/year?

Probably not, at least right now. The Total Health membership includes the GLP-1 report along with other health screenings, so you’re not paying $299 just for GLP-1 insights. But the GLP-1 findings alone are too small to drive clinical decisions. The GLP1R variant accounts for a few extra pounds of weight loss, and the GIPR variant predicts nausea on tirzepatide. Neither result would change a prescriber’s standard approach of starting low and adjusting based on your real-world response. If you already have a 23andMe account with raw data, you may be able to check for these variants through third-party tools without the subscription.

Does my DNA determine how much weight I’ll lose on a GLP-1?

Only partially. The 23andMe study found that genetics explain a small portion of the variation in GLP-1 outcomes. Most of the difference between people comes from factors like starting weight, diet, exercise, dose, and medication adherence. The 5% to 20% weight loss range on GLP-1 drugs is broad, and your genetics might nudge you a few pounds in one direction, but they don’t determine your outcome.

Should I choose semaglutide over tirzepatide if I’m worried about nausea?

The GIPR variant finding suggests some people are genetically predisposed to worse nausea on tirzepatide specifically. But nausea is common across all GLP-1 medications, and most patients manage it successfully through slow dose titration. If you start tirzepatide and experience severe nausea that doesn’t improve with dose adjustments, switching to semaglutide is reasonable regardless of your genetics. Talk to your provider about your options through services like PlushCare or Hims.

Keep reading

• Semaglutide vs tirzepatide: Which wins?
• Ro: Provider profile and pricing
• GLP-1 eligibility quiz
• Wegovy profile