Does drinking coffee help you live longer?

Americans drink an estimated 517 million cups of coffee every day, according to the National Coffee Association, making it the most popular beverage in the U.S. other than water. Drinking coffee has been associated with a wide range of health benefits. But will it help you live longer? 

Many large studies suggest that coffee’s biologically active compounds, including caffeine, may help keep inflammation, chronic health conditions and even certain cancers at bay. But because correlation doesn’t equal causation, there’s still not enough evidence to definitively say that drinking a morning brew will result in a longer life.

Because “the data is from retrospective studies [and] not randomized trials” there is “not really enough strong data to recommend people to drink more coffee,” Dr. Chip Lavie, the medical director of cardiac rehabilitation and preventive cardiology at the John Ochsner Heart and Vascular Institute in New Orleans, told Live Science in an email. 

That said, what exactly have these large studies tying coffee drinking with health benefits and longer lifespans found? According to a 2018 study published in the journal Progress in Cardiovascular Diseases, there are over 1,000 biologically active compounds in coffee. One major component, called chlorogenic acid improves glucose metabolism and insulin sensitivity. This translates to improving the body’s ability to process sugar. Insulin sensitivity refers to how sensitive the body’s cells are in response to insulin. High insulin sensitivity allows the cells of the body to use blood glucose more effectively, reducing blood sugar. A 2019 systematic review in the Journal of Traditional and Complementary Medicine has shown that these effects reduce the risk of type 2 diabetes. A systematic review of nine studies found that people who drank more than six cups of coffee per day were at a lower risk of developing type 2 diabetes compared with those who drank fewer than two, according to a 2013 paper in Journal of the American College of Cardiology. 

Compounds such as melanoids, quinines, lignan and trigonelline have antiinflammatory effects and are antioxidants, meaning they prevent or slow damage to cells caused by free radicals — unstable molecules produced by the body when it processes food and reacts to the environmental pollutants and toxins. Free radicals can lead to inflammation and contribute to a range of diseases, including cardiovascular and inflammatory disease, cataract, and cancer, according to a study published in Pharmacognosy Review.

Of coffee drinkers, 84 per cent have their cup of joe with breakfast, according to the National Coffee Association(opens in new tab), suggesting that most people drink coffee for its caffeine. Caffeine stimulates the central nervous system by blocking signals in the brain that would usually tamp down its activity. It’s also a weak bronchodilator, meaning it makes breathing easier by relaxing the muscles in the lungs and widening the airways (bronchi). However, one of the main effects caffeine has on the body is on the heart. According to the Progress on Cardiovascular Diseases study, “Habitual coffee consumption is also associated with lower risks for cardiovascular (CV) death and a variety of adverse CV outcomes, including coronary heart disease (CHD) [and] congestive heart failure (HF).” 

This may seem counterintuitive to some people. “Caffeine seems bad, as it can raise heart rate and [blood pressure] acutely and theoretically increase [cardiac] rhythm disturbances,” Lavie said. However, most data suggest that regular caffeine use is safe and associated with reductions in cardiovascular disease mortality and even total mortality over a period of decades, he said.

Live Science