There is no conclusive evidence that moderate caffeine or coffee consumption is a risk factor for the development of human cancer. Indeed, in 1997, the World Cancer Research Fund published a comprehensive review of diet and cancer in which it stated that ‘most evidence suggests that regular consumption of coffee and/or tea has no significant relationship with the risk of cancer at any site’. Thousands of research projects have been carried out to investigate any links between coffee consumption and the development of cancer in the human body. The overwhelming scientific evidence on coffee health shows that moderate coffee consumption, of 4-5 cups per day, is perfectly safe for the general population and may confer health benefits. Pregnant women should however moderate their intake following the guidelines issued by the Food Standards Agency in 2008, to 200mg caffeine per day from all sources.
Introductory
There is no conclusive evidence that moderate caffeine or coffee consumption is a risk factor for the development of human cancer. Indeed, the World Cancer Research Fund published a comprehensive review of diet and cancer in which it stated that `most evidence suggests that regular consumption of coffee and/or tea has no significant relationship with the risk of cancer at any site’ (1).
Coffee and cancer
In 1990, IARC, the International Agency for Research on Cancer held a monograph on Coffee, Caffeine, Tea & Maté, the latter being a beverage unique to South American countries. The purpose of this monograph was to assess whether these beverages should be classified as being cancer causing (carcinogenic). Coffee was cleared in all areas with the exception of bladder cancer where there was insufficient evidence available at that time, though several studies have since been published that clearly show no link between coffee consumption and bladder cancer (2 & 3).
A large study of almost 43,000 people conducted in Norway, one of the largest consumers of coffee per capita, also found no association between coffee consumption and overall risk of cancer (4). Furthermore, a review of results from studies conducted over the past two decades concludes that the amount of caffeine as usually consumed in coffee, does not have genotoxic, mutagenic or carcinogenic effects (5). Indeed, published research has even suggested that coffee drinking may have a protective effect against the development of colon cancer or colorectal cancer (6 & 7), liver cancer (8 – 11), kidney cancer (12) and ovarian cancer (13), however, the mechanism for these effects has yet to be found.
Summary
Thousands of research projects have been carried out to investigate any links between coffee consumption and the development of cancer in the human body. The overwhelming scientific evidence shows that moderate coffee consumption, of 4-5 cups per day, is perfectly safe for the general population and may confer health benefits. Pregnant women should however moderate their intake following the guidelines issued by the Food Standards Agency, to 200mg caffeine per day from all sources.
References
1. World Cancer Research Fund. Food, Nutrition and the Prevention of Cancer: a Global Perspective, 1997
2. Sala M. Cancer Causes and Control, Volume 11, 2000
3. Zeegers MPA. Cancer Causes and Control, Volume 12, 2001
4. Stensvold I and Jacobsen BK. Cancer Causes and Control, Volume 5, 1994
5. Nehig A and Debry G. World Review of Nutrition and Diabetes, Volume 79, 1996
6. Woolcott CG. European Journal of Cancer Prevention, Volume 11, 2002
7. Giovannucci E. American Journal of Epidemiology, Volume 147, 1998
8. Shimazu T. International Journal of Cancer, Volume 116, 2005
9. Larsson & Wolk, Gastroenterology, Volume 132, 2007
10. Bravi F. Hepatology, 2007
11. Tanaka K. Cancer Sci, Volume 98, 2007
12. Lee JE. International Journal of Cancer, Volume 15, 2007
13. Tworoger S. Cancer, Volume 112, 2008
