How Does Coffee Consumption Affect Longevity and Disease Risk?

The short answer

Regular coffee consumption is one of the most consistent dietary associations with lower mortality in epidemiological research. Drinking 3–5 cups per day is associated with a 12–16% lower all-cause mortality risk. Benefits are seen for type 2 diabetes (25–30% risk reduction), Parkinson's disease (30–40% risk reduction), liver cirrhosis (40% risk reduction), and several cancers. Both caffeinated and decaffeinated coffee show benefits, suggesting the active components are not solely caffeine.

What the evidence actually shows

A 2017 umbrella review by Poole et al. in the BMJ, synthesising 201 meta-analyses, found that coffee consumption was associated with the largest risk reduction for liver cirrhosis (−39%), followed by Parkinson's disease (−29%), type 2 diabetes (−25%), and all-cause mortality (−17% at 3–4 cups/day). Gunter et al. (2017) in Annals of Internal Medicine, using data from 521,330 European adults, found that higher coffee consumption was associated with lower all-cause mortality in both men and women across 10 European countries. Freedman et al. (2012) in the NEJM, following 402,260 US adults, found a dose-response relationship between coffee consumption and lower mortality, with the strongest associations for heart disease, respiratory disease, stroke, diabetes, and infections.

"Coffee consumption was associated with the largest risk reduction for liver cirrhosis (−39%), Parkinson's disease (−29%), and type 2 diabetes (−25%)."

— Poole et al., BMJ 2017

What the major health authorities say

MedlinePlus notes that moderate coffee consumption is generally safe for most adults and may have health benefits. The NIA identifies coffee as a food that has been associated with health benefits in observational studies. The FDA considers up to 400mg of caffeine per day (approximately 4 cups of coffee) safe for healthy adults. The European Food Safety Authority has reached similar conclusions.

Practical implications

For most healthy adults, 3–5 cups of coffee per day is associated with health benefits and is safe. Both caffeinated and decaffeinated coffee appear beneficial, suggesting that polyphenols (chlorogenic acids) and other bioactive compounds — not just caffeine — are responsible for the health effects. Coffee consumed with large amounts of sugar, cream, or flavoured syrups loses its health benefit and adds significant calories. Unfiltered coffee (French press, espresso) contains cafestol and kahweol, which raise LDL cholesterol — filtered coffee (drip, pour-over) is preferable for cardiovascular health.

Where reasonable people still disagree

• Whether the associations between coffee and health outcomes are causal or reflect confounding by healthy lifestyle factors that correlate with coffee consumption.
• The relative contributions of caffeine versus polyphenols to coffee's health effects — important for determining whether decaf is equivalent.
• Whether the cardiovascular benefits of coffee outweigh the risks for individuals with hypertension, arrhythmias, or anxiety disorders.