An article published
in The BMJ reviewed
201 meta-analyses of observational research and 17 meta-analyses of
interventional research and found that coffee consumption was more often
associated with benefits than harm.
The researchers found that drinking three cups of coffee a day
was associated with the greatest benefit in terms of cardiovascular disease,
coronary heart disease, and stroke, when compared with not drinking coffee.
Consumption at this level was associated with a 19% lower risk of mortality
from cardiovascular disease, a 16% lower risk of mortality from coronary heart
disease, and a 30% lower risk of stroke mortality.
Increasing consumption to more than three cups a day was not
associated with harm, but the beneficial effects were less pronounced. Women seemed to benefit more from greater coffee consumption
than men in terms of reduced risk of coronary heart disease and cardiovascular
disease mortality, but less so in stroke mortality.
Review of the studies showed that coffee drinkers had lower
incidence of cancer. High consumption of coffee was associated with a lower
risk of prostate cancer, endometrial cancer, melanoma, oral cancer, leukemia,
non-melanoma skin cancer, and liver cancer.
Coffee consumption also seemed to have a beneficial effect on gastrointestinal
system. Coffee drinkers had a 29% lower risk of non-alcoholic fatty liver, a 27%
lower risk of liver fibrosis, and a 39% lower risk of liver cirrhosis.
The picture was mixed for consumption of coffee in pregnancy.
High versus low consumption was associated with a higher risk of low birth
weight and pregnancy loss. No significant
association, however, was found between any category of coffee consumption and
third trimester preterm birth, neural tube defects, and congenital
malformations of the oral cleft or cardiovascular system.
High versus low consumption of coffee was also associated with
an increased risk of fracture in women but a decreased risk in men.
In conclusion moderate coffee consumption seems safe, and it can
be incorporated as part of a healthy lifestyle by most of the adults.
