# R8 | anthropic/claude-haiku-4.5 | run 1

## Prompt

What is the current scientific consensus on moderate, daily and heavy coffee consumption and health? Summarize and cite authoritative sources.

## Response

Current scientific consensus shows that moderate coffee consumption—typically 3–5 cups daily (up to 400 mg caffeine)—is safe for most adults and associated with substantial health benefits, while heavy consumption may carry increased cardiovascular risks. The evidence is robust across multiple large-scale meta-analyses and systematic reviews.

## Safe Consumption Levels

For most adults, up to 400 mg of caffeine daily (equivalent to 3–5 cups of 8-ounce brewed coffee) is considered safe [American Heart Association](https://newsroom.heart.org/news/coffee-and-heart-health-how-many-cups-of-caffeinated-coffee-are-safe-to-drink-each-day). An umbrella review of 201 meta-analyses found the largest health benefits at 3–4 cups daily [BMJ](https://www.bmj.com/content/bmj/359/bmj.j5024.full.pdf). Consumption beyond 4–5 cups daily may increase certain cardiovascular risks.

## Cardiovascular Effects

**Moderate consumption (2–4 cups daily)** shows protective effects:
- 17% lower risk of all-cause mortality [BMJ](https://www.bmj.com/content/bmj/359/bmj.j5024.full.pdf)
- 19% lower risk of cardiovascular mortality [BMJ](https://www.bmj.com/content/bmj/359/bmj.j5024.full.pdf)
- 15% lower risk of cardiovascular disease [BMJ](https://www.bmj.com/content/bmj/359/bmj.j5024.full.pdf)
- Reduced risk of heart failure and stroke [American Heart Association](https://newsroom.heart.org/news/coffee-and-heart-health-how-many-cups-of-caffeinated-coffee-are-safe-to-drink-each-day)

**Heavy consumption (>4 cups daily)** presents mixed findings. Some studies report increased myocardial infarction risk [Springer](https://link.springer.com/article/10.1186/s12872-026-05693-0), while others find no significant increase in coronary heart disease overall [Springer](https://link.springer.com/article/10.1186/s12872-026-05693-0). Blood pressure effects are paradoxical: 1–3 cups associated with higher hypertension risk in normotensive individuals, but >3 cups linked to lower risk [American Heart Association](https://newsroom.heart.org/news/coffee-and-heart-health-how-many-cups-of-caffeinated-coffee-are-safe-to-drink-each-day).

## Other Health Outcomes

Moderate consumption is associated with reduced risk of type 2 diabetes, chronic kidney disease, several cancers, liver disease, and neurological conditions [BMJ](https://www.bmj.com/content/bmj/359/bmj.j5024.full.pdf). Coffee without added sugar, syrups, or cream retained these benefits; additives may diminish protective effects [American Heart Association](https://newsroom.heart.org/news/coffee-and-heart-health-how-many-cups-of-caffeinated-coffee-are-safe-to-drink-each-day).

## Important Exceptions

Pregnant women should limit or avoid coffee—high versus low consumption was associated with increased risks of low birth weight, preterm birth, and pregnancy loss [BMJ](https://www.bmj.com/content/bmj/359/bmj.j5024.full.pdf). Women at elevated fracture risk should also exercise caution [BMJ](https://www.bmj.com/content/bmj/359/bmj.j5024.full.pdf).

## Key Distinction: Coffee vs. Energy Drinks

Energy drinks and energy shots contain 3–4 times more caffeine per ounce than regular coffee and are associated with cardiovascular harm, including high blood pressure and arrhythmias [American Heart Association](https://newsroom.heart.org/news/coffee-and-heart-health-how-many-cups-of-caffeinated-coffee-are-safe-to-drink-each-day).

Are you interested in the specific mechanisms explaining coffee's protective health effects?
