
I read a lot of GLP-1 research so you don’t have to, and 2026 has been a genuinely weird year for this drug class — real wins, a real flop, and a lawsuit pile that’s growing fast. Here’s the roundup, no spin.
THE GOOD
Heart failure: A large real-world study found starting a GLP-1 cut hospitalization or death from heart failure with preserved ejection fraction (HFpEF) by roughly 40% overall — 42% for semaglutide, 58% for tirzepatide, compared to a standard diabetes drug. That’s a big enough signal that the FDA added heart-failure outcome data to the prescribing information this year.
Addiction: This one surprised even researchers. A Lancet-published randomized trial found semaglutide reduced heavy drinking days in people with alcohol use disorder. Separately, a large study of veterans found GLP-1 users had lower rates of alcohol, opioid, and nicotine use disorder. Nobody fully understands the mechanism yet, but the drugs seem to turn down cravings generally, not just food cravings.
Suicide risk — actually good news for once: Remember the suicidal-ideation warning that got attached to these drugs a few years back? In January 2026, the FDA said it’s moving to remove that warning from semaglutide, tirzepatide, and liraglutide labels, based on a meta-analysis covering 91 trials and nearly 108,000 patients, plus a separate claims study comparing over 2 million people. No increased risk found. That’s a real reversal, and it doesn’t get nearly the coverage the original scare did.
THE NOT-SO-GOOD
Alzheimer’s —The Not the outcome we were hoping for: But that is why we do research.
Novo Nordisk’s EVOKE and EVOKE+ trials tested oral semaglutide in people with early Alzheimer’s. It did not show a cognitive benefit versus placebo. This was a genuinely big, well-run trial, and it just didn’t pan out. If you saw hype about GLP-1s as a dementia treatment, file that under “not yet, maybe not ever.”
Muscle loss: A preprint (meaning not yet peer-reviewed — treat it as early data) looked at roughly 670,000 GLP-1 users and found tirzepatide caused more lean muscle mass loss than semaglutide, with about 1 in 10 tirzepatide users hitting a pattern researchers called a “depletive metabotype” — losing more than 20% of body weight while losing more than 5% lean mass. This is exactly why every doctor keeps telling you to lift weights and eat your protein while you’re on these drugs. It’s not optional.
Litigation: As of August 2026, there are nearly 4,000 lawsuits consolidated against Novo Nordisk and Eli Lilly, up almost 200% since January 2025. Most allege gastroparesis (stomach paralysis), with smaller numbers citing bowel blockage or gallbladder problems. A separate, newer batch of cases focused on a vision condition called NAION is still working through the evidence stage — the vision risk itself is genuinely unresolved in the research, not just in the courtroom. Bellwether trials are expected late this year. No settlements yet.
None of this is medical advice, and none of it means “don’t take these drugs” — I’m on tirzepatide myself and I’m not stopping over a preprint or a pending lawsuit. It does mean: talk to your doctor about your specific risk factors, get your labs and body composition checked periodically, and don’t let a scary headline (or an overly rosy one) make the decision for you instead of your doctor.
I keep a running list of research updates like this for my own tracking — some of it’s in the book, and I’ll keep posting updates here as new studies land.
Sources
- AJMC, “GLP-1s Reduced Adverse Heart Failure Events by 40% in Patients With HFpEF,” 2026.
- Medscape, heart-failure data added to GLP-1 prescribing information, 2026.
- The Lancet, randomized trial of semaglutide for alcohol use disorder, 2026.
- NBC News, GLP-1s and substance use disorder (veterans study), 2026.
- FDA.gov, update on suicidality evaluation for GLP-1 receptor agonists / Pharmacy Times coverage, Jan. 2026.
- Clinical Trials Arena, AD/PD 2026 coverage of Novo Nordisk EVOKE/EVOKE+ Alzheimer’s trial results.
- medRxiv (preprint, not peer-reviewed), tirzepatide vs. semaglutide lean mass loss, April 2026.
- mdlupdate.com, GLP-1 receptor agonist multidistrict litigation status, Aug. 2026.







