Great news coffee drinkers! Another study - this time a large analysis of over 200 studies found that coffee consumption is linked to many health benefits. The best results were from drinking 3 to 4 cups of coffee daily (as compared to none), with a reduction in "all cause" mortality (death from any cause), and cardiovascular disease and death.
They also found a lower risk of cancer in general, and with a lower risk of several specific cancers (endometrial, prostate, melanoma, non-melanoma skin cancer, liver cancer) and neurological (Parkinson's disease, Alzheimer's disease, and depression), metabolic (including type 2 diabetes, metabolic syndrome), and liver conditions.
However, during pregnancy high coffee consumption (as compared to low or no consumption) was associated with low birth weight, preterm birth in the first and second trimester, and pregnancy loss. The researchers also found an association between coffee drinking and a small risk of fracture in women, but not in men. Decaffeinated coffee seemed to have many of the same benefits as caffeinated coffee - especially at 2 to 4 cups a day.
[UPDATE: A 2020 review of studies found that ingesting caffeine during pregnancy is linked to health problems and that there is no safe level during pregnancy. In other words, caffeine and caffeinated beverages should be avoided during pregnancy and when trying to conceive.]
Excerpts from Science Daily:
Three to four cups of coffee a day linked to longer life
Drinking coffee is "more likely to benefit health than to harm it" for a range of health outcomes, say researchers in The BMJ today. They bring together evidence from over 200 studies and find that drinking three to four cups of coffee a day is associated with a lower risk of death and getting heart disease compared with drinking no coffee. Coffee drinking is also associated with lower risk of some cancers, diabetes, liver disease and dementia. However, they say drinking coffee in pregnancy may be associated with harms, and may be linked to a very small increased risk of fracture in women.
The included studies used mainly observational data, providing lower quality evidence, so no firm conclusions can be drawn about cause and effect, but their findings back up other recent reviews and studies of coffee intake. As such, they say, excluding pregnancy and women at risk of fracture, "coffee drinking appears safe within usual patterns of consumption" and they suggest that coffee could be safely tested in randomised trials.
To better understand the effects of coffee consumption on health, a team led by Dr Robin Poole, Specialist Registrar in Public Health at the University of Southampton, with collaborators from the University of Edinburgh, carried out an umbrella review of 201 studies that had aggregated data from observational research and 17 studies that had aggregated data from clinical trials across all countries and all settings. (Original study.)