While nothing is conclusive as of yet, the researchers believe that people who drink coffee regularly as a part of their daily routine are possibly getting more health benefits rather than harm.
But before we can start giving coffee to patients, we needed to know whether coffee drinking had any recognised harms, so we chose to conduct an umbrella review to capture as much important information about coffee drinking and health as we could.
A couple of notable points: Researchers did not define the exact amount of coffee that constituted one cup, or whether the coffee consumed was instant, espresso or whether the beans producing the beverage were roasted.
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.
Harmful associations were mostly nullified by suitable adjustment for smoking, except in pregnancy, while there was a link between coffee drinking and fracture risk in women but not men. Coffee drinking is also associated with lower risk of some cancers, diabetes, liver disease and dementia.
Coffee was also associated with a lower risk of several cancers, including prostate, endometrial, skin and liver cancer, as well as type 2 diabetes, gallstones and gout.
Finally, there seemed to be beneficial associations between coffee consumption and Parkinson's disease, depression and Alzheimer's disease.
"As such, even small individual health effects could be important on a population scale".
He added: "Does coffee prevent chronic disease and reduce mortality?"
Coffee drinking during pregnancy is linked to low birth weight. Poor people. Additonally, it's stressed that drinking the right type of coffee is vital, free of cream, sugar or milk. We simply do not know.
"The answer to both questions is "no". Of course, there are a number of other reasons to take up coffee drinking, such as its general deliciousness.
The exception to those who would benefit are pregnant women; they are advised to limit their caffeine intake to 200 milligrams per day, as to avoid any increased risk of miscarriage.
Tom Sanders, emeritus professor of nutrition and dietetics at King's College London, said: "While the conclusion is reassuring to coffee consumers, there are some limitations". Caffeine also acutely increases blood pressure, albeit transiently. But they said their findings support other recent reviews and studies of coffee intake.