---
type: Object
title: Coffee
description: A brewed beverage made from the roasted, ground seeds of the Coffea plant,
  valued as both a stimulant and a sensory product.
tags:
- coffee
- beverage
- botany
- species
- health
resource: raw/coffee-guide.md
timestamp: '2026-07-16T14:53:19Z'
citadel_version: 0.3.0
---

Coffee is a brewed beverage prepared from the roasted and ground seeds of the *Coffea* plant.[^s1] Despite being universally called "beans," these seeds are the pits of a small fruit commonly known as the coffee cherry: once the cherries are harvested, the seeds are separated from the surrounding pulp, dried, roasted, ground, and finally infused in hot water to produce the drink.[^s1] Coffee is valued both as a daily stimulant, owing to its naturally occurring [caffeine](../concepts/caffeine.md), and as a sensory product whose flavor reflects its botanical variety, growing region, [processing](../concepts/coffee-processing.md), and [roast](../concepts/coffee-roasting.md).[^s1]

The genus *Coffea* contains many species, but two account for essentially all commercial production: [Arabica](arabica.md) (*Coffea arabica*) and [Robusta](robusta.md) (*Coffea canephora*, universally known by that trade name).[^s2] The table below summarizes the principal contrasts between them.[^s3]

| Trait | Arabica | Robusta |
| --- | --- | --- |
| Share of world production | ~60-70% | remainder |
| Growing altitude | Higher | Lower |
| Hardiness / disease resistance | Lower | Higher |
| Yield | Lower | Higher |
| Caffeine content | Baseline | ~2x that of Arabica |
| Typical flavor | Sweeter, more complex | Harsher, more bitter |

Large long-term population studies have found that drinking 3-4 cups of coffee a day is associated with a lower risk of type 2 diabetes and Parkinson's disease.[^s4] The word "associated" matters, though: these are observed patterns across large groups of people, not proof that coffee itself prevents either condition, since people who drink moderate coffee may differ from others in additional ways, and separating coffee's own effect from everything else about a person's life would need long-run controlled trials that are difficult to run; the honest summary is that moderate coffee drinking is linked to some good outcomes, but "linked to" is as far as the evidence currently goes, and coffee should not be taken up purely as medicine on the strength of it.[^s5]

Coffee is naturally acidic and can stimulate stomach activity, which a sensitive stomach may not tolerate well, especially on an empty one; common remedies are to eat something alongside the coffee, switch to a darker [roast](../concepts/coffee-roasting.md) or a cold-[brewed](../concepts/coffee-brewing.md) coffee — both tend to be gentler — or simply cut back, since the sensitivity is usually about the individual rather than a flaw in the coffee.[^s6]

## See also
- [Arabica](arabica.md)
- [Robusta](robusta.md)
- [History of Coffee](../concepts/history-of-coffee.md)
- [Coffee Processing](../concepts/coffee-processing.md)
- [Coffee Roasting](../concepts/coffee-roasting.md)
- [Coffee Brewing](../concepts/coffee-brewing.md)
- [Caffeine](../concepts/caffeine.md)

## Sources
[^s1]: [raw/coffee-guide.md](../../raw/coffee-guide.md), line 3 — definition, coffee cherry, and production process (ingested 2026-07-16)
[^s2]: [raw/coffee-guide.md](../../raw/coffee-guide.md), line 9 — the two commercial species and their trade names (ingested 2026-07-16)
[^s3]: [raw/coffee-guide.md](../../raw/coffee-guide.md), lines 17-24 — Arabica vs. Robusta comparison table (ingested 2026-07-16)
[^s4]: [raw/coffee-health-faq.md](../../raw/coffee-health-faq.md), line 49 — 3-4 cups/day associated with lower type 2 diabetes and Parkinson's risk (ingested 2026-07-16)
[^s5]: [raw/coffee-health-faq.md](../../raw/coffee-health-faq.md), line 53 — association is not causation; controlled trials are hard to run (ingested 2026-07-16)
[^s6]: [raw/coffee-health-faq.md](../../raw/coffee-health-faq.md), line 65 — coffee's acidity can upset a sensitive stomach, and remedies (ingested 2026-07-16)
