People have been drinking coffee since at least the 15th century, and it's been a staple of the workplace for more than a century. But it's only fairly recently that science has explained some of its incredible health benefits.
As an avid coffee fan, I've written a lot over the years on new scientific studies about coffee's health benefits. Here's a quick recap of some of the best of them.
If you're not drinking coffee yet, these studies might just change your mind.
1. Drinking coffee reduces your risk of death from any cause.
We have to start here: A fascinating British study of 500,000 people found that habitual coffee drinkers were less likely to die than non-coffee drinkers over the 10-year span of the study.
Not just less likely to die of certain causes: less likely to die of anything. As in, they cheat death. Find me a better argument than that!
As for why, it's a bit of a mystery. One theory is that since coffee contains more than 10,000 chemical compounds that protect cells from damage, it might just inhibit many causes of death that scientists haven't isolated yet.
Related: A Spanish study of 20,000 people found that people over age 45 had a 30 percent lower risk of death for every two additional cups of coffee they drank each day. Once again, that's a lower risk of death from any cause of death.
2. It's linked to lower risk of heart disease, stroke, and even suicide.
Another massive study -- this one from the Harvard School of Public Health, and following 200,000 doctors and nurses over 30 years -- linked coffee consumption to lower risk of death from heart disease, stroke, diabetes, neurological diseases, and even suicide.
Drink a cup of coffee a day, and the chance of death from these causes dropped 6 percent. Drink between three and five cups, and it dropped 15 percent.
Separately, researchers examined records of 5,209 people in the Framingham Heart Study, the nation's longest-running epidemiological study, and found a strong correlation between coffee consumption and lower risk of heart disease.
For every additional cup of coffee people drank, their risk of suffering heart failure or stroke went down 8 percent, compared to non-coffee drinkers.
Yet another study, this one from South Korea, followed 25,000 and also found that drinking moderate amounts of coffee each day was associated with fewer early warning signs of heart disease.
In all three studies, the observations were correlative, not causative. But the numbers were huge, and the repetitive nature of the studies is eye-opening.
3. It prompts your body to burn fat.
This one comes from a study at the University of Nottingham in England, and was published in the journal, Scientific Reports.
Researchers used a thermal imaging system to measure the temperatures of people's necks, which in turn let them figure out how much brown adipose tissue (otherwise known as BAT or brown fat) they were burning.
My colleague Geoffrey James wrote about this study first on Inc.com: "Coffee heats up your BAT, which causes your body to more efficiently convert WAT [white adipose tissue] into energy. Or put even more simply: Coffee literally burns fat. Woohoo!"
The study's authors say they don't know whether it's the caffeine in coffee, or something else, that causes the fat burning.
"We are currently looking at caffeine supplements to test whether the effect is similar," said Michael Symonds, co-authored of the study.
4. It appears to counteract part of the aging process.
This was a smaller study, conducted at Stanford University--just 100 coffee drinkers over several years, conducted by researchers at Stanford University. But its theory was well-defined and quite intriguing.
It starts with the idea that as people get older, they experience a "fundamental inflammatory mechanism associated with human aging and the chronic diseases that come with it," according to a Stanford statement on the study.
But drinking coffee, because of the high caffeine content, could counteract the chemical reactions that trigger the inflammation over time, according to the study.
"That something many people drink -- and actually like to drink -- might have a direct benefit came as a surprise to us," explained study coauthor Mark Davis, a professor of microbiology and immunology at Stanford.
5. It suggests improved brain health and lower risk of age-related cognitive decline.
Yet another study focusing on another one of those 10,000 different chemical compounds found that coffee consumption "does seem to have some correlation to a decreased risk" of both Alzheimer's disease and Parkinson's diseases," said Donald Weaver, co-director of the Krembil Brain Institute at the University of Toronto.
The secret here secret seems to be connected to a kind of chemical called phenylindanes, which are created during the roasting process. It appears that these chemicals may help stop the buildup of two toxic proteins in the brain, called tau and beta-amyloid, which have been linked to both Alzheimer's and Parkinson's.
"So phenylindanes are a dual inhibitor. Very interesting--we were not expecting that," Weaver told Medical News Today, which reported on the study.
The science never ends
As for the optimal amount of coffee to drink each day, a study in the March 2019 edition of The American Journal of Clinical Nutrition says the "tipping point where caffeine started to negatively affect cardiovascular risk" is five cups.
If we're using between six and eight ounces as the standard cup of coffee, that works out to about 35 ounces a day.
Oh, and if you can't bear to drink that much, don't fret.
As my colleague Jessica Stillman found, even just thinking about coffee gives you at least part of the benefit: an energy boost that mimics the effects of actually drinking a cup.