A recent study has found that drinking a cup of black coffee daily can help lower the risk of death by 14 per cent. However, if you add milk or sugar, the benefits might reduce. Researchers said that the same link was not seen for coffee with high amounts of added sugar or saturated fat. The study was published in The Journal of Nutrition.

Fang Fang Zhang, from Tufts University in the US, and senior author of the study, said, "The health benefits of coffee might be attributable to its bioactive compounds, but our results suggest that the addition of sugar and saturated fat may reduce the mortality benefits."

Researchers analysed date of nine consecutive cycles of the US' National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018, linked to national death data.  They also looked at the responses of more than 46,000 adults aged 20 years and above who completed first-day 24-hour dietary questionnaires.

Coffee consumption was categorised by type; caffeinated or decaffeinated, sugar, and saturated fat content, and outcomes of death studied included those from any cause, cancer, and cardiovascular disease.

Bingjie Zhou, a PhD graduate from Tufts University and first author said, "Few studies have examined how coffee additives could impact the link between coffee consumption and mortality risk, and our study is among the first to quantify how much sweetener and saturated fat are being added."

The authors wrote, "Consuming black coffee and coffee with low levels of added sugar and saturated fat was associated with a 14 per cent lower risk of all-cause mortality, compared with no coffee consumption."

Consuming two to three cups a day could lower the risk of death due to any cause by 17 per cent, whereas taking more than three cups daily was not associated with additional reductions, the researchers said.

Further, the link between coffee and a lower risk of death by cardiovascular disease weakened when more than three cups of coffee were taken a day, they added.