How many cups of coffee a day is good for your health?

Moderate coffee drinking — about three to five cups a day — has been previously linkedexternal link to reduced risks for dying early. A new study suggests that when people drink coffee could factor into these observed benefits. The researchers found that adults who drank coffee before noon saw the greatest reductions in dying early from any cause and from cardiovascular disease. 

For this analysis, the investigators assessed nutrition data collected from more than 40,000 U.S. adults who participated in a long-term nutrition study. About half of participants, 52%, drank coffee. More than one-third, 36%, drank coffee in the morning. The rest, 16%, drank coffee throughout the day. After controlling for a variety of factors, the researchers found that adults who limited their coffee consumption to between 4 a.m. and noon were 16% less likely to die from any cause throughout nearly 10 years compared to adults who didn’t drink coffee. They were also 31% less likely to die from cardiovascular disease. These associations didn’t extend to people who drank coffee throughout the day. 

The researchers believe the benefits of drinking coffee in the morning may be due to two factors. First, drinking coffee with caffeine early in the day as opposed to in the afternoon or evening is less likely to alter a person’s sleep patterns, which supports their overall and cardiovascular health. Second, the anti-inflammatory effects of coffee, whether it’s caffeinated or not, may be strongest in the morning since this is when levels of inflammation can peak. The authors note more research is needed to study these and other associations linked to coffee’s health benefits. 

The findings from this study published in the European Society of Cardiologyexternal link. The research was supported by NHLBI and the National Institutes of Diabetes and Digestive and Kidney Diseases.