Study Ties Weight Regain After Diet Pills to Higher Suicide-Thought Odds; Experts Caution on Cause

SEOUL — Adults who used prescription weight-loss drugs and later gained weight had higher odds of reporting suicidal thoughts than people who never took the medicines, according to a South Korean survey study that researchers and outside clinicians say cannot prove the pills caused the distress.

A team led by Son Ki-young, a family-medicine professor at Asan Medical Center in Seoul, analyzed 27,741 adults who took part in the Korea National Health and Nutrition Examination Survey from 2013 through 2022 — 10,908 men and 16,833 women. In the prior year, 846 said they had taken doctor-prescribed drugs for weight control; 26,895 said they had not.

Compared with nonusers, medication users were 1.9 times as likely to report depression lasting more than two weeks, twice as likely to have sought mental-health counseling, 2.7 times as likely to report suicidal thoughts, 1.9 times as likely to report a suicide plan and 1.7 times as likely to report an attempt, after the team adjusted for other factors. Among users, 9.9% said they had considered suicide in the past year, versus 4.5% of nonusers. Plans were reported by 2.2% versus 1.4%; attempts by 1.7% versus 0.6%. Depression lasting two weeks was reported by 22.1% of users and 11.4% of nonusers. Counseling rates were 8.4% and 3.4%.

The sharpest figure was among people who took the drugs and still gained weight. Their odds of suicidal thoughts were 4.2 times those of nonusers. Depression and counseling odds in that subgroup were about 1.9 and 1.8 times higher.

"The increase in suicide-related index, among those who regained weight after weight-loss medication, is not just related to the neurological and psychiatric effects of the medicine itself. It is likely to be connected in a complex way to the psychological and social elements related to failing to control one's weight," the researchers wrote. They said missing a target or watching the scale rebound can intensify frustration and dissatisfaction. The paper appeared Aug. 23 in the Korean Journal of Family Practice under a title linking weight-loss drug use and weight change with depression and suicide-related thoughts and behavior.

The study is observational and cross-sectional: people were asked about drug use and symptoms at roughly the same time. It cannot show which came first. Bonnie Mitchell, a licensed professional clinical counselor in California, told Fox News Digital that the paper "shows a correlation between weight-loss drug use and self-reported mental health symptoms, but it cannot prove causation" and "does not demonstrate that weight-loss medications directly induce depression or suicidal thoughts."

The calendar of the survey is as important as the odds ratios. Most of the decade predates wide use of modern GLP-1 and GIP drugs such as high-dose semaglutide (Wegovy) and tirzepatide (Zepbound/Mounjaro) in South Korea. Mitchell said the sample largely reflects older agents used there in that period, including phentermine, diethylpropion, phendimetrazine, topiramate and orlistat. Stimulant appetite suppressants have long been tied to anxiety, insomnia and mood change. Treating that mix as a verdict on today's injectables would overread the data. Korean reporting on the paper made the same distinction.

Obesity itself is bound up with mood. Mitchell noted that people with severe obesity already have higher baseline rates of depression, anxiety and body-image distress, and that a one-time survey cannot separate old symptoms from new ones after a prescription. Weight regain, she said, can bring guilt, shame and a sense of failure even when the drug is not a stimulant. That psychosocial path matches the Seoul team's own wording.

Regulators have been walking a different path for the newest drugs. In January 2026 the U.S. Food and Drug Administration asked manufacturers to remove suicidal-ideation-and-behavior language from labels of Saxenda (liraglutide), Wegovy and Zepbound after a review that, the agency said, "did not identify an increased risk" of those outcomes with GLP-1 receptor agonists. A meta-analysis of 91 placebo-controlled trials covering 107,910 patients — 60,338 on a GLP-1 drug and 47,572 on placebo — did not show higher rates of suicidal thoughts or behavior, or of anxiety, depression, irritability or psychosis, versus placebo. The original warnings, the FDA said, had been carried over from older weight-loss medicines. Novo Nordisk said it was pleased with the recommendation for Saxenda and Wegovy. A Lilly spokesperson said the company appreciated "the FDA's careful consideration of this important safety issue" and would keep working with the agency.

Lilly's consumer safety pages have still told patients to watch mood, behavior, feelings or thoughts and to call a clinician if changes are "new, worse or worry you." On its medical-information site the company has said that after reviewing trials and reports it identified "no increased risk" of suicidal ideation or psychiatric adverse effects. Novo has said fewer than 1% of trial participants on semaglutide 2.4 mg had suicidal ideation or behavior and that there was "no difference between semaglutide 2.4 mg and placebo." Those statements describe trial and label science. They do not erase the Korean finding that people who use diet pills and then gain weight report more despair.

Clinicians still treat mood as something to ask about. Mitchell recommended a mental-health history before a new prescription — past depression, bipolar disorder, prior suicidal thinking — and check-ins every four to eight weeks while doses rise. She listed warning signs that should trigger a call to a clinician: persistent low mood, loss of interest, agitation or panic, insomnia, new thoughts of self-harm, or personality change noticed by family. "Any active suicidal thoughts require immediate emergency medical care," she said. "If a patient develops emergent depression or suicidal ideation during treatment, clinicians should discontinue the weight-loss medication and connect the patient with psychiatric support."

People in crisis can contact the 988 Suicide & Crisis Lifeline in the United States.

What the Seoul paper adds is not a new black-box warning for Wegovy. It is a reminder that weight-loss drugs sit inside a story patients already tell themselves about control and failure. Older Korean pills, many of them stimulants, were used by 846 survey respondents. Those who then saw the scale rise reported suicidal thoughts at more than four times the rate of people who never took the drugs. The authors did not claim the molecule alone did that. They pointed to psychology and social pressure as well as any direct drug effect.

The next studies need to do what this one could not: follow the same people over time, name the drug, and separate obesity, regain, stimulant effects and GLP-1 biology. Until then, the responsible reading is narrow. Association is not cause. Regain after a diet pill is a high-risk moment for mood. The newest injectables have not shown an excess suicide signal in large placebo trials. Patients who start any of these medicines still need someone to ask how they are sleeping — and what happens if the weight comes back.