Coffee consumption and disease specific mortality

Research into coffee consumption and CVD has suggested that a moderate intake of coffee may reduce CVD mortality risk^20-37. Moderate coffee consumption can be defined as 3-5 cups per day, based on the European Food Safety Authority’s review of caffeine safety¹⁷.

Specifically in relation to coronary heart disease, several studies suggest a protective effect at intakes of approximately 3-5 cups per day with the association resembling a U-shaped curve^27,30,31.

Studies reviewing associations between coffee consumption and stroke have suggested that a moderate intake is associated with a reduced risk of stroke, particularly in women^32-37.

• Two 2013 reviews suggested that the effects of habitual coffee consumption are neutral and potentially beneficial when considering cardiovascular risks such as coronary heart disease, congestive heart failure, arrhythmias, and stroke^4,5. The authors concluded that large epidemiological studies suggest that regular coffee drinkers have a reduced risk of both cardiovascular and all cause mortality^4,5.
• A further 2013 review concluded that habitual coffee consumption is associated with reduced mortality, both for all-cause and cardiovascular deaths. The authors specifically noted that coffee intake is associated with a reduced risk of heart failure, stroke, diabetes mellitus and some cancers, and showed neutral to reduced risks for both atrial and ventricular arrhythmias¹⁴. However, they suggested that caffeine may increase anxiety, insomnia, calcium loss and possibly the risk of fractures in some, advising that adequate calcium intake was key for tea and coffee drinkers¹⁴.
• A 2018 population study suggested that in men, coffee was associated with an increased risk of cancer and cardiovascular mortality, and a reduced risk of respiratory and other causes of death¹³.

Cancer

In 2016, the International Agency for Research on Cancer (IARC) reviewed all available research on coffee and cancer, including research published since its original review in 1991, and found no clear association between coffee intake and cancer at any body site. In some cases, research suggested coffee drinking is associated with a reduced occurrence of certain cancers. IARC therefore classified coffee in Group 3, for agents “not classifiable as to carcinogenicity to humans”¹⁶. IARC classified beverages consumed at very high temperatures (defined as over 65°C) as “probably carcinogenic to the human oesophagus”¹⁶. However, 65°C is significantly hotter than the temperature at which most people can comfortably drink coffee without scalding their mouth and tongue^38,39,
coffee is typically drunk at temperatures below 60°C.

• A 2017 review of 39,685 men and 43,124 women suggested that increased frequency of coffee consumption was associated with a lower risk of cancer incidence in both men and women. Coffee consumption frequency was also associated with reduced mortality from cancer¹⁵.
• Contrarily, a 2018 population study suggested that in men, coffee was associated with an increased risk of cancer¹³.