OK. So maybe we’ve started off with a slight exaggeration there? Coffee may be neither a silent killer, nor a health promoting elixir – but given some of the content that is published out there you may be forgiven for thinking otherwise.
Coffee and the Liver
Many authors write that one outcome of coffee drinking to be a negative effect on the liver. They state that because the liver uses enzymes to break down caffeine, there are fewer enzymes available to break down other substances, which means that that drinking coffee is doing damage to your liver.
However this rationale is flawed. Further research shows that moderate coffee consumption (2-5 cups a day) is beneficial to liver health. The research conducted by Modi et al. (2010), and Wakai et al. (2007) – and the many sources that they quoted of both case-control studies and cohort studies – showed that coffee consumption can indeed reduce the risk of heptocellular carcinoma (primary cancer of the liver), and that higher coffee consumption has been inversely associated with the incidence of chronic liver disease.
So, although a moderate intake of coffee could in fact be beneficial for some aspects of liver health, as with all things an excessive intake (greater than 5 cups per day) could lead to high toxicity level in the liver, which may lead to complications.
Coffee and Pregnancy
Coffee and pregnancy do not mix. Women should not drink caffeine during pregnancy, as an intake of more than 2 cups a day (200mg of caffeine) doubled the risk of miscarriage, and that more than 1 cup could can lower birth weight.
These findings are reinforced by the Care Study Group (2008), who showed that fetal growth restriction increased with caffeine consumption even at relatively low levels (100mg/1 cup per day). In addition, studies conducted on mice showed that caffeine intake during pregnancy caused offspring to have more body fat and reduced cardiac function in adulthood.
Although this research is not yet conclusive, and there are other studies published that refute these points, the possible risk associated with complications arising from drinking coffee during pregnancy cannot be ignored. All people should be aware of this risk, so that they can monitor their intake accordingly.
Coffee and Fatigue
Coffee drinking negatively affects your sleep patterns and, primarily for this reason, anyone suffering from anxiety should avoid any form of caffeine.
The consumption of coffee also brings about onset of ‘adrenal fatigue’ because although coffee is a stimulant, it overworks the adrenal glands, tiring out both them and you.
Most people understand that coffee is a stimulant and that caffeine is a drug that is useful if you need to stay awake for short periods. However, many do not realise the negative effect this can have over time, nor the fact that ongoing usage can increase your feeling of tiredness. Indeed even a small amount of caffeine can lead to caffeinism which increase the incidence of depression, anxiety and insomnia.
Coffee and Antioxidants
Most of the benefits of drinking coffee are linked to the intake of antioxidants, and those in coffee have been linked to the prevention of Alzheimer’s, dementia and prostate cancer among other things. There are several studies on either side of this fence, talking of the benefits of the antioxidants in coffee and antioxidants in general, however the interesting point to note here is that in your average American diet, over 50% of antioxidants come from coffee.
This poses a separate question to those promoting that we all quit coffee drinking, of whether it is of benefit to remove 50% of the antioxidants from a persons diet? Regardless of the answer to this question, it remains important for everyone to look to other sources of antioxidants (i.e. green tea, fresh fruit and vegetables, vitamin E C), whether eliminating coffee from you diet or not.
Environmental Factors Affecting Research
There is an interesting relationship that can skew research into the benefits or negatives of coffee consumption. This is that coffee consumption increases with income. As we also know general health, longevity, and most health indicators improve with wealth. Therefore any correlation between health and coffee intake would be skewed by these results.
Conversely the eating of food with little nutritional value, increased sugar intake, and smoking are also associated with coffee drinking. These correlating factors would influence a negative relationship between coffee and health, as those who eat food with higher fat or sugar content are more likely to have poorer health, with an increased incidence of heart disease, diabetes, stroke etc.
Summary
Many authors have written emotively about the variou positives and negatives associated with coffee drinking. Aside from the negative affects of coffee intake during pregnancy, which must again be emphasised, studies show that there are few side effects to a moderate intake of coffee. Where tests show there to be a negative effect, they are often describing large dosages of caffeine (900mg, or 9 cups of coffee, a day).
In fact, the vast majority of studies focus on the negative effects of caffeine, not of coffee. There needs to be much more research done on coffee as a whole rather than the singular component of caffeine. There is little research as to the benefits of antioxidants and other chemical in coffee, although this is difficult and costly to monitor due to outside influences such as environmental or socio-economic factors.
Alternatively, you can always take the caffeine out of the equation with decaf. The process for making decaffeinated coffee has improved markedly in the past 10 years. Where previously harsh, and dangerous, chemical solvents were used, now water extraction and supercritical carbon dioxide extraction are used and these processes are pure in that they add no chemicals to the coffee, they simply remove the caffeine. That way you can get most of the benefit, and eliminate most of the negative.
Unless of course, like me, you are working at 2am in the morning and only the real thing will do. Now, where did I put that coffee…
For more articles on health related topics, please click here: http://www.docsorders.co.nz/NewsArchive.aspx
References:
Bloom, D., Canning, D. (2000). Science 18 February 2000: Vol. 287 (no. 5456), pp. 1207-1209. doi: 10.1126/science.287.5456.1207
Caffeine. (2011). Retrieved from http://en.wikipedia.org/wiki/Caffeine
Care Study Group. (2008). Maternal caffeine intake during pregnancy and risk of fetal growth restriction: a large prospective observational study. British Medical Journal. 2008, 337, a2332. doi: 10.1136/bmj.a2332
Jiang, J., Xu, N., Zhang, X., Wu, C. (2007). Lipids changes in liver cancer. Journal of Zhejiang University – Science B Volume 8, Number 6, 398-409. doi: 10.1631/jzus.2007.B0398
Klein, S. (2010). Coffee: Is it healthier than you think? Retrieved from http://articles.cnn.com/2010-04-28/health/coffee.studies_1_coffee-drinkers-coffee-studies-national-coffee-association?_s=PM:HEALTH
McKeith, G. (2004). The plan that will change your life you are what you eat. London, England: Penguin Group.
Modi, A., Feld, J., Park, Y., Kleiner, D., Everhart, J., Liang, J., Hoofnagle, J. (2010). Increased caffeine consumption is associated with reduced hepatic fibrosis. Hepatology. 51(1): 201–209. doi: 10.1002/hep.23279
Murray, M., Pizzorno, J. (1998). Encyclopedia of Natural Medicine. (2nd ed.). New York, New York: Three Rivers Press.
University of Guelph. (2011). Got a Hankering for Fast Food? Skip the Coffee, Study Says. Retrieved from http://www.uoguelph.ca/news/2011/04/got_a_hankering.html
Wakai, K., Kurozawa, Y., Shibata, A., Fujita, Y., Kotani, K., Ogimoto, I., Naito, M., Nishio, K., Suzuki, H., Yoshimura, T., Tamakoshi, A. (2007). Liver cancer risk, coffee, and hepatitis C virus infection: a nested case–control study in Japan. British Journal of Cancer (2007) 97, 426–428. doi:10.1038/sj.bjc.6603891
Wendler, C., Busovsky-McNeal, M., Ghatpande,S., Kalinowski,A., Russell, K., Rivkees, S. (2009). Embryonic caffeine exposure induces adverse effects in adulthood. The Journal of the Federation of American Societies for Experimental Biology, 2009 April; 23(4), 1272–1278. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2660649/?tool=pmcentrez