Apr 29, 2024, 3:00 AM ETInterview

Johann Hari: They’re Lying To You About The Side Effects Of Ozempic!

Author Johan Hari discovered the prevalence of Ozempic/GLP-1 agonists when a friend at a Hollywood party revealed widespread use among celebrities and non-celebrities to achieve gaunt, "filtered" looks.
Hari spent a year taking the drugs himself, losing three stone (approx. 19 kg) in one year, to investigate the "extraordinary benefits and disturbing risks."
The drug mimics the gut hormone GLP-1, which remains in the system for a week rather than a few minutes, signaling satiety and reducing appetite by roughly 80%.
Costs vary significantly by region: approximately £250 per month in the UK and $800–$1,200 per month in the US.
The market is dominated by Novo Nordisk (Ozempic/Wegovy) and Eli Lilly (Mounjaro/Zepbound), with the global market projected to reach $200 billion by 2030.

Neurological Effect: While initially thought to act on the gut, neuroscientists now believe the drugs primarily act on the brain, altering food preferences and reducing the reward value of high-calorie foods.
Three Theories on Brain Function:
- Reward Dampening: The drugs may suppress the brain's reward system, reducing the pleasure derived from food, which carries risks of depression or suicidal feelings in a minority of users.
- Preference Resetting: The drugs may act like a "factory reset," lowering set points for food cravings to healthier levels.
- Satiety System Upregulation: The drugs may specifically enhance the brain's satiety system (the "stop eating" signal) without dampening overall life enjoyment, though this is debated.
Addiction Potential: Animal studies suggest GLP-1 agonists reduce compulsive behavior towards alcohol, cocaine, heroin, and fentanyl by up to 50%, potentially acting as a broad "self-control" booster, though human data is still emerging.
Metabolic Changes: The drugs trigger biological changes similar to bariatric surgery, potentially lowering the body's "set point" for weight, counteracting the natural metabolic slowdown that occurs during dieting.

Weight Regain: Approximately 70% of users regain lost weight within one year of stopping the medication.
Muscle Loss: Users can lose 20–30% of lean muscle mass, posing long-term risks of sarcopenia (frailty), falls, and reduced mobility in older age.
Pancreatitis: Risk increases by a factor of nine; the condition is described as "excruciatingly painful," often worse than childbirth.
Thyroid Cancer: One French study indicated a 50–75% increased relative risk of thyroid cancer (a condition affecting a small percentage of the population), though the European Medicines Agency has not yet confirmed a causal link.
Gallstones: Increased risk of gallbladder disease is associated with rapid weight loss from these drugs.
Mental Health: Reports of suicidal ideation, anxiety, and depression exist; some scientists attribute this to the removal of "comfort eating" or unmet expectations after weight loss.
Unknown Unknowns: Scientists warn of potential long-term side effects not yet visible in short-term trials, such as potential links to dementia similar to late-stage antipsychotic side effects.

The "Obesogenic" Environment: The drugs are described as an "artificial solution to an artificial problem" caused by a food supply high in ultra-processed foods that destroys natural satiety signals.
Eating Disorders: There is significant concern regarding young women misusing the drugs for self-starvation; the drugs are easily obtainable online without proper BMI verification.
Addiction Transfer: Evidence from bariatric surgery suggests that removing food as a coping mechanism can lead to the transfer of addiction to alcohol, gambling, or shopping (observed in ~10% of surgery patients).
Body Image and Stigma: The shift toward using pharmaceuticals for weight loss challenges the cultural narrative of "sin" and "willpower," creating friction between those who choose diet and exercise and those who use drugs.
Access Inequality: High demand has led to shortages where patients with Type 2 diabetes cannot access the medication they need for life-saving blood sugar control, prompting calls for rationing based on medical need.

Failure of Traditional Diets: Research by Professor Tracy Mann indicates only ~10% of people maintain significant weight loss via diet and exercise long-term; the average person loses only 2 pounds over two years.
Historical Failures: The conversation draws parallels to previous diet drugs like "Fen-Phen" (withdrawn in the 1990s for causing heart valve damage and pulmonary hypertension) and amphetamines, which caused psychosis and addiction.
Japan as a Model: Japan maintains a 4.5% obesity rate (vs. 26% in the UK and 42% in the US) through government-led systemic changes, including:
- Mandatory nutritionists in schools.
- Bans on processed school foods.
- Cultural norms of eating only to 80% fullness.
- Workplace health monitoring ("Metabo Law").
Market Disruption: Stock prices for fast-food chains (Krispy Kreme), confectionery (Nestlé), and orthopedic surgery providers (hip/knee replacements) are already falling due to predicted reductions in consumption and obesity-related surgeries.

Population Usage: Predictions suggest 50% of the population could be using these drugs in the coming decades if the obesogenic environment remains unchanged and drugs become oral pills (avoiding injections).
Pricing and Patents: The patents on semaglutide expire in 2032, potentially dropping costs to ~$40/month, which could lead to mass usage, including among non-obese individuals.
Genetic vs. Environmental: Research on Japanese populations in Hawaii demonstrates that obesity is environmentally driven, not genetic, as the diaspora adopts the obesity rates of their host country.
Future Drug Variants: Newer drugs (e.g., GLP-1/GIP dual agonists, triple agonists) are in development, promising weight loss of 24% or more, with different risk profiles.
Long-term Uncertainty: Experts warn that the long-term effects on the human brain and metabolism remain largely unknown, with the potential for "unknown unknowns" to emerge over decades of widespread use.

Hari's personal conclusion is to prioritize the known, catastrophic risks of obesity (heart attack, diabetes, cancer, blindness, amputation) over the unknown or manageable risks of the drug.
He recommends the drugs for those with a BMI >35 or severe obesity who have failed other methods, but advises against use for healthy individuals seeking vanity slimming.
The "Magic Pill" is framed not as a perfect solution, but as a complex trade-off requiring individual risk assessment and broader societal reform to address root causes in the food system.