Health and pharmacology of Coffee

Coffee ingestion on average is about a third of that of tap water in North America and Europe. Worldwide, 6.7 million metric tons of coffee were produced annually in 1998–2000, and the forecast is a rise to 7 million metric tons annually by 2010.

Scientific studies have examined the relationship between coffee consumption and an array of medical conditions. Findings are contradictory as to whether coffee has any specific health benefits, and results are similarly conflicting regarding negative effects of coffee consumption.

Coffee consumption has been linked to breast size reduction and taking regular hits of caffeine reduces the risk of breast cancer. Coffee appears to reduce the risk of Alzheimer's disease, Parkinson's disease, heart disease, diabetes mellitus type 2, cirrhosis of the liver, and gout. It increases the risk of acid reflux and associated diseases. Some health effects of coffee are due to its caffeine content, as the benefits are only observed in those who drink caffeinated coffee, while others appear to be due to other components. For example, the antioxidants in coffee prevent free radicals from causing cell damage.

Coffee's negative health effects are mostly due to its caffeine content. Research suggests that drinking caffeinated coffee can cause a temporary increase in the stiffening of arterial walls. Excess coffee consumption may lead to a magnesium deficiency or hypomagnesaemia, and may be a risk factor for coronary heart disease. Some studies suggest that it may have a mixed effect on short-term memory, by improving it when the information to be recalled is related to the current train of thought, but making it more difficult to recall unrelated information. About 10% of people with a moderate daily intake (235 mg per day) reported increased depression and anxiety when caffeine was withdrawn, and about 15% of the general population report having stopped caffeine use completely, citing concern about health and unpleasant side effects.[81] Nevertheless, the mainstream view of medical experts is that drinking three 8-ounce (236 ml) cups of coffee per day (considered average or moderate consumption) does not have significant health risks for adults.

American scientist Yaser Dorri has suggested that the smell of coffee can restore appetite and refresh olfactory receptors. He suggests that people can regain their appetite after cooking by smelling coffee beans, and that this method might also be used for research animals.