Coffee and skin cancer
There is no research to currently suggest that coffee consumption is linked to skin cancer. Caffeine, however, may protect skin cellsagainst the harmful effects of UVB radiation64,65, with some research suggesting a reduced risk of malignant melanoma associated with caffeinated coffee consumption.
- A 2016 systematic review and meta-analysis concluded that there is a possible association between regular coffee consumption and a reduced risk of melanoma, although the authors suggested that further research is required64
- A 2016 meta-analysis concluded that a linear dose response effect was observed between a reduced risk of malignant melanoma and caffeinated coffee consumption, but not decaffeinated coffee65
Coffee and lung cancer
Although a high consumption of coffee (more than 5 cups per day) has been associated with an increased risk of lung cancer, residual confounding effects of smoking or other factors have been identified66.
Indeed, IARC’s 2016 review stated that although a positive association was observed in some studies, this is most likely to be explained by confounding factors such as smoking. The report concluded that there was inadequate evidence to suggest any association between lung cancer and coffee consumption1.
- A 2016 meta-analysis of 12,276 cases of lung cancer and 102,516 controls suggested a significant association between intake of 3 or more cups of coffee per day and increased risk of lung cancer in men but not in women, in American and Asian populations, and smokers66
Coffee and brain tumours
Coffee consumption may be linked to a reduced risk ofbrain tumours but given the number of studies is limited, more research is required to confirm this inverse association67. Similarly, IARC has not reviewed coffee consumption in relation to brain tumours1.
- A 2019 meta-analysis of 11 articles suggested that there was an inverse association between coffee consumption and brain cancer risk, especially in Asian populations67
Maternal coffee consumption and childhood leukemia
There are limited studies in this area with some variable results68-70. IARC’s review concluded that a lack of consistency amongst studies led to inconclusive and inadequate evidence of any association between coffee consumption and childhood leukaemia1. Pregnant and breastfeeding women are advised by EFSA to consume no more than 200mg of caffeine per day from all sources, which is equivalent to 2-3 cups of coffee10.
- A 2015 meta-analysis comprising a total of 3,649 cases and 5,705 controls conclude that their findings ‘confirm the detrimental association between maternal coffee consumption and childhood leukemia risk, and provide indications for a similar role for maternal cola or energy drink consumption’68
- A further 2015 study examining parental smoking, maternal alcohol, coffee and tea consumption during pregnancy, and childhood acute leukemia, concluded that childhood acute leukemia was not associated with coffee consumption during pregnancy, but an association was seen between coffee consumption and acute lymphoblastic leukemia69
- A 2018 pooled analysis from the Childhood Leukaemia International Consortium suggested that whilst there was no association with any maternal coffee consumption, there was evidence of a positive exposure response. This led the authors to conclude that, despite some limitations, their findings suggest coffee may be associated with an increased risk of acute lymphoblastic leukaemia and they supported the advice to limit caffeine intake during pregnancy70