ByWALLA! HEALTH

Who doesn’t love coffee? Especially these days. Now, a sharp new study has found that daily coffee consumption may reduce the risk of premature death by up to 17%. However, this finding is valid only when coffee is consumed in its simplest form – black or with almost no additions.
The study, which lasted more than a decade and followed nearly 50,000 adults in the U.S., found that coffee drinkers lived longer compared to those who didn’t drink at all. However, the health benefit was observed only among those who drank black coffee or added minimal amounts of sugar and saturated fat. Sweet and frothy coffee drinks – the ones that star on coffee shop menus – provided no health benefits and may even cancel out coffee’s positive effect.
The study, conducted at Tufts University, included 46,322 participants aged 20 and over, who took part in U.S. government surveys between 1999 and 2018. The data was analyzed over a follow-up period of 9 to 11 years, cross-referenced with national mortality data. During this time, 7,074 participants died – 1,176 of them from cancer and 1,089 from heart disease.

Compared to those who didn’t drink coffee, coffee drinkers had a lower risk of death. The most significant effect was seen in those who drank 2–3 cups per day, with a 17% reduction in the risk of death. Even drinking less than one cup a day was associated with an 11% risk reduction.
The researchers also examined exactly what participants were drinking – meaning, what additions they put in their coffee. Each beverage was rated according to the amount of sugar and saturated fat it contained per standard cup (240 ml). Black coffee was associated with a 14% reduction in risk of death from any cause. Coffee that contained less than 2.5 grams of sugar and less than one gram of saturated fat maintained the same reduction.
But as the quantities increased – the effect disappeared. Coffee with higher levels of sugar or saturated fat was not associated with any reduction in mortality. These findings are concerning, as the average American coffee contains about 3.24 grams of sugar and 0.52 grams of saturated fat per cup – far beyond the healthy threshold.
The researchers also found that the health effect of coffee is specifically related to caffeine. Decaffeinated coffee was not associated with increased life expectancy. In contrast, caffeinated coffee was linked to lower overall mortality and mortality from heart disease. The hypothesis is that caffeine contributes to health by speeding up metabolism, reducing inflammation, and improving insulin sensitivity. In addition, coffee contains other active compounds such as chlorogenic acid and polyphenols, which have antioxidant and anti-inflammatory properties.
Surprisingly, the positive link between coffee and longevity disappeared in people who also drank tea, but the reason for this is unclear.