Remember when drinking coffee felt like a guilty pleasure? Not anymore. Here's how coffee is actually good for your health.

Mug of black coffee
Photo by Meredith

How did coffee go from mild vice to superbeverage? After all, coffee was once tied to cancer and thought to harm the heart. But it turns out, early studies on coffee and health were often marred because they failed to take into account cigarette smoking, a harmful habit that often goes hand-in-hand with coffee drinking. Once coffee was uncoupled from smoking, researchers began to see a different story emerge. These days, not only have the supposed health risks of drinking coffee been called into serious question, but coffee is now thought to have many protective qualities.

So where does the current science stand on coffee as a healthy beverage? We've put together a little primer highlighting recent studies. One caveat as you pore over the list: most of the studies referenced below lacked the randomized controlled trials that can help confirm results; as Berkeley Wellness reminds us, "most of these potential health benefits are based on observational studies, so they don't prove cause and effect."

Mug of Black coffee
| Photo by Meredith

Here's what the buzz is all about:

1) Cardiovascular Disease

A systematic review of 36 studies looking at long-term coffee drinking found that people who drank 3-to-5 cups of black coffee per day were at the lowest risk for developing cardiovascular disease. And people who drank 5 or more cups didn't have higher risk than non-coffee drinkers. British researchers, meanwhile, linked drinking coffee to improved chances of surviving a heart attack and to being less likely to die prematurely from cardiac damage than non-coffee drinkers.

2) Dementia and Other Cognitive Issues

Studies suggest that coffee might offer some protection against developing dementia, including Alzheimer's disease. Coffee has also been positively linked with other neurological issues, including depression and cognitive decline. It's also linked with a reduced risk of suicide.

3) Parkinson's Disease

Coffee drinking was associated with a lower risk of developing Parkinson's disease. A study at Harvard found that a daily habit of 4 or 5 cups of coffee cut the risk of Parkinson's almost in half when compared to people who drank little or no coffee.

4) Stroke

A review of 11 studies found that people who drank 2-to-6 cups of black coffee every day were at lower risk for stroke than non-coffee drinkers. A conclusion that was confirmed by a subsequent meta-analysis.

5) Liver Disease

Drinking coffee was linked to a lower risk of developing the kind of liver damage caused by excessive alcohol consumption. For patients with hepatitis C, coffee was shown to improve responses to antiviral therapy.

6) Cancer

Studies have shown that upping your coffee drinking can lower the risk of liver cancer. There is positive news related to prostate cancer and breast cancer. Also, a study in 2012 connected coffee consumption with a lower risk of a type of skin cancer, basal cell carcinoma. Overall, a study that reviewed all types of cancer suggested that coffee might be linked with "reduced overall cancer incidence and that the more you drank, the more protection was seen," according to The New York Times. The one caveat is for smokers who drink coffee; with coffee-drinking smokers, increasing the amount of coffee shows a greater risk of lung cancer.

7) Type 2 Diabetes

Coffee was shown to reduce the risk of developing Type 2 diabetes. People who drank at least 6 cups of coffee every day had the lowest risk.

8) Gallstones

Caffeinated coffee has metabolic effects that may help prevent gallstone disease. "All coffee brewing methods showed a decreased risk," read a portion of the study's abstract. However, the "risk of symptomatic gallstone disease also declined with increasing caffeine intake...decaffeinated coffee was not associated with a decreased risk."

9) Longevity

There is an association between drinking coffee and living longer. And it's not just that coffee may be protective against disease, coffee is also linked to the kinds of things that can help keep you alive, including increasing driver safety and improving workouts.

Finally, and not to be a big ol' buzzkill, but the key to keeping coffee consumption on the healthy side is to avoid adding piles of sugar and heaps of cream. For comparison, a large Starbucks Venti White Chocolate Mocha weighs in at 22 grams of fat, 79 grams of carbs, and a whopping 580 calories; a cup of regular black coffee has zero fat, zero carbs, and about 5 calories.