People who have been drinking coffee only in the 'morning' were found to be 20% less likely to have metabolic syndrome compared to those who do not drink coffee at all. Interestingly, this association was not observed among people who evenly distributed their coffee consumption from morning to evening.
According to a study published in the 'British Journal of Nutrition,' a research team led by Maoqi Shen from the Department of Cardiovascular Medicine at the Second Xiangya Hospital of Central South University in China analyzed dietary data from 11,632 adults aged 20 and older who participated in the U.S. National Health and Nutrition Examination Survey between 2003 and 2018. The participants were categorized into 'morning-focused' and 'all-day distributed' groups based on their coffee consumption times, and their prevalence of metabolic syndrome was compared with that of non-drinkers.
As a result, the morning-focused group had a 20% lower likelihood of having metabolic syndrome than non-drinkers. This association remained consistent even after adjusting for factors that could influence the outcome, such as △gender △age △income level △smoking status △drinking habits △exercise habits △sleep quality △dietary quality and total caloric intake.
In contrast, no significant difference in the prevalence of metabolic syndrome was observed in the all-day distributed group, which consumed coffee across multiple time periods throughout the day, compared to non-drinkers. The lower likelihood of metabolic syndrome in the morning-focused group was relatively consistently observed regardless of whether coffee consumption was low or high.
Metabolic syndrome is a condition where multiple metabolic abnormalities, such as abdominal obesity, high blood pressure, high blood sugar, high triglycerides, and low HDL cholesterol, occur simultaneously in an individual. It is considered a risk factor that increases the likelihood of developing cardiovascular disease and type 2 diabetes.
In this study, the association between the morning-focused pattern and a lower likelihood of metabolic syndrome was relatively stronger among women, those aged 40 or younger, and individuals with normal weight, underweight, or overweight status.
The research team suggested that the metabolic effects of antioxidant bioactive components in coffee, such as caffeine and polyphenols, may interact with the human body's daily circadian rhythm. They noted that since late-day caffeine intake can affect sleep and the biological clock, it is necessary to consider not only the total amount of coffee consumed but also the time of consumption.
This study is a cross-sectional observational study comparing coffee consumption habits and health status at a single point in time. It does not prove a causal relationship that morning coffee directly prevents metabolic syndrome or that afternoon and evening coffee harms metabolic health. There is also a possibility that factors such as coffee type, the addition of sugar and cream, and changes in consumption habits over time were not fully reflected.
In light of this, experts advised, "When drinking coffee, it is desirable to avoid adding excessive amounts of sugar, syrup, or cream, and to reduce the habit of drinking coffee in the late afternoon or evening, which can interfere with sleep." They further recommended, "Even when drinking coffee in the morning, it is advisable to enjoy it in moderate amounts alongside a breakfast that includes vegetables, fruits, whole grains, and protein foods."
in THEBIO
