Coffee linked to slower biological ageing among those with severe mental illness

Study validity and causality

• Many commenters stress correlation vs causation: coffee drinkers might simply differ in wealth, race, stress, or overall lifestyle.
• Some note the paper’s controls seem limited; no clear mechanism is demonstrated, so the observed association could be driven by unmeasured factors (e.g., people who feel better are more likely to drink coffee).
• Several point to the broader problem of nutritional epidemiology: small effects, many variables, p‑hacking, and “citation farming.” Ioannidis’ critique of exaggerated diet–longevity claims is cited.
• Calls are made for randomized controlled trials; skepticism that impressive observational findings would survive them.

Scope of the effect (severe mental illness vs general population)

• One thread asks if the effect is specific to people with severe mental illness, noting another study where instant coffee correlated with worse outcomes.
• A reply claims coffee benefits “everyone” but has a larger impact in groups with already shortened lifespan; others find this uncertain.
• Some suggest schizophrenia/SMI patients may be self‑medicating with caffeine (similar to nicotine), but causality could run either way.

Mechanisms and biology

• Speculation includes: MAO inhibitors and other bioactive compounds in coffee, antioxidants, appetite suppression, and reduced caloric intake.
• Debate over whether caffeine itself is key or whether non‑caffeine compounds in brewed coffee matter more.
• Question raised whether other stimulants (ADHD meds, nicotine) would show similar aging effects.

Health effects, risks, and dependence

• Several describe clear subjective benefits for mood and severe mental illness; for some, coffee is “like medicine.”
• Others report anxiety, jitters, migraines, or hypertension exacerbation; one cites evidence that heavy coffee intake is dangerous in severe hypertension.
• Disagreement over whether strong reliance on coffee is “addiction” vs non‑harmful dependence; withdrawal headaches and cycles of quitting are described.
• Some recommend tea as a gentler alternative.

Anecdotes, taste changes, and tolerance

• Multiple stories of shifting from sugary drinks to black coffee and more “bland” whole foods with age.
• Others report increasing GI intolerance with age; suggestions include darker roasts, milk, baking soda, small‑batch/fresh beans, and avoiding mass‑produced coffee.

Coffee culture, cost, and social factors

• Coffee shop social interaction is floated as a possible confounder (barista relationships, workplace coffee breaks).
• Discussion of rising coffee prices, raw bean shortages, and differences between instant, robusta, and arabica.