Coffee is a brewed drink prepared from roasted coffee beans, which are the seeds of "berries" from the Coffea plant. Coffee plants are cultivated in over 70 countries, primarily in the equatorial regions of the Americas, Southeast Asia, India and Africa. The two most commonly grown are the highly regarded arabica, and the less sophisticated but stronger and more hardy robusta. The latter is resistant to the coffee leaf rust, Hemileia vastatrix, but has a more bitter taste. Once ripe, coffee beans are picked, processed, and dried. Green (unroasted) coffee beans are one of the most traded agricultural commodities in the world. Once traded, the beans are roasted to varying degrees, depending on the desired flavor, before being ground and brewed to create coffee.
Health effects
Potential benefits
Coffee is no longer thought to be a risk factor for coronary heart disease. A 2012 meta-analysis concluded that people who drank moderate amounts of coffee had a lower rate of heart failure, with the biggest effect found for those who drank more than four cups a day. Moreover, in one study, habitual coffee consumption was associated with improved vascular function.
In a ten-year study among 50,739 US women (mean age, 63 years) free of depressive symptoms at baseline (in 1996), coffee consumption was negatively correlated with risk of developing clinical depression. A review published in 2004 indicated a negative correlation between suicide rates and coffee consumption.It was suggested that the action of caffeine in blocking the inhibitory effects of adenosine on dopamine nerves in the brain reduced feelings of depression.
Polyphenols in coffee have been shown to affect free radicals in vitro, but there is no evidence that this effect occurs in humans. Polyphenol levels vary depending on how beans are roasted as well as for how long. As interpreted by the Linus Pauling Institute and the European Food Safety Authority, dietary polyphenols, such as those ingested by consuming coffee, have little or no direct antioxidant value following ingestion.
Potential risks
Coffee's adverse effects are more common when taken in excess, with potential health risks due mainly to its caffeine content and can therefore be avoided by drinking less coffee or using decaffeinated coffee.
Oily components called diterpenes are present in unfiltered coffee and coffee brewed using metal filters, but not in coffee brewed using paper filters.
Moderate amounts of coffee (50–100 mg of caffeine or 5–10 g of coffee powder a day) are well tolerated by most elderly people. Long-term studies of both risk and potential benefit of coffee consumption by elderly people, including assessment on symptoms of Alzheimer's disease and cognitive impairment, are not conclusive, according to one 2015 review.
Coffee consumption can lead to iron deficiency anemia by interfering with iron absorption, especially in mothers and infants
Health effects
Potential benefits
Coffee is no longer thought to be a risk factor for coronary heart disease. A 2012 meta-analysis concluded that people who drank moderate amounts of coffee had a lower rate of heart failure, with the biggest effect found for those who drank more than four cups a day. Moreover, in one study, habitual coffee consumption was associated with improved vascular function.
In a ten-year study among 50,739 US women (mean age, 63 years) free of depressive symptoms at baseline (in 1996), coffee consumption was negatively correlated with risk of developing clinical depression. A review published in 2004 indicated a negative correlation between suicide rates and coffee consumption.It was suggested that the action of caffeine in blocking the inhibitory effects of adenosine on dopamine nerves in the brain reduced feelings of depression.
Polyphenols in coffee have been shown to affect free radicals in vitro, but there is no evidence that this effect occurs in humans. Polyphenol levels vary depending on how beans are roasted as well as for how long. As interpreted by the Linus Pauling Institute and the European Food Safety Authority, dietary polyphenols, such as those ingested by consuming coffee, have little or no direct antioxidant value following ingestion.
Potential risks
Coffee's adverse effects are more common when taken in excess, with potential health risks due mainly to its caffeine content and can therefore be avoided by drinking less coffee or using decaffeinated coffee.
Oily components called diterpenes are present in unfiltered coffee and coffee brewed using metal filters, but not in coffee brewed using paper filters.
Moderate amounts of coffee (50–100 mg of caffeine or 5–10 g of coffee powder a day) are well tolerated by most elderly people. Long-term studies of both risk and potential benefit of coffee consumption by elderly people, including assessment on symptoms of Alzheimer's disease and cognitive impairment, are not conclusive, according to one 2015 review.
Coffee consumption can lead to iron deficiency anemia by interfering with iron absorption, especially in mothers and infants