People who drink coffee mainly in the morning are 20 percent less likely to have metabolic syndrome than those who drink no coffee at all, according to new research. The same association was not found among people who spread their coffee consumption throughout the day. The findings suggest that when it comes to coffee's health benefits, timing may matter as much as quantity.
The results come from a research team led by Maoqi Sun of the Department of Cardiovascular Medicine at the Second Xiangya Hospital of Central South University in China, who analyzed data from 11,632 adults aged 20 and older who participated in the US National Health and Nutrition Examination Survey, according to the Korea Food Communication Forum on Wednesday.
The research team analyzed data from the US National Health and Nutrition Examination Survey collected between 2003 and 2018, examining what time of day participants drank coffee. Coffee-drinking habits fell into two broad patterns: morning-concentrated and all-day spread. The most striking finding involved the morning-concentrated group. Even after accounting for factors that could influence the results — including age, sex, lifestyle and diet — people who drank coffee primarily in the morning were 20 percent less likely to have metabolic syndrome than non-coffee drinkers.
Metabolic syndrome refers to a cluster of conditions — including abdominal obesity, high blood pressure, elevated blood sugar, high triglycerides and low HDL cholesterol — that together raise the risk of cardiovascular disease and diabetes. It can increase the long-term risk of both conditions even without obvious symptoms, making management important.
Notably, no statistically significant association with metabolic syndrome was found among those who spread their coffee intake throughout the day. When the research team analyzed both the amount and timing of coffee consumption, the morning-concentrated group generally showed a lower likelihood of having metabolic syndrome regardless of how much coffee they drank. The association was particularly strong among women, adults aged 40 and under, and those of normal weight, underweight or overweight.
Beyond caffeine, coffee contains a range of bioactive compounds, including chlorogenic acid. Previous research has raised the possibility that these compounds may influence glucose metabolism and inflammation. The research team also suggested that the body's circadian rhythm could help explain why the timing of coffee consumption makes a difference.
"Morning-concentrated coffee consumption was associated with a lower prevalence of metabolic syndrome," the team wrote in the paper. "This shows that when studying the relationship between coffee and health, it is necessary to consider not only the amount consumed but also the timing."
However, the findings should not be interpreted to mean that morning coffee prevents metabolic syndrome. The study was an observational analysis of existing survey data examining the relationship between coffee-drinking timing and metabolic syndrome status at a single point in time — not a clinical trial in which participants were assigned to drink morning coffee and then tracked over time for disease development. Whether morning coffee directly reduces the risk of metabolic syndrome requires further research. The findings were published online July 9 in the British Journal of Nutrition.
kty@heraldcorp.com
