Cut down on coffee intake in this window to lower your risk of premature death, research suggests

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Drinking coffee has been repeatedly linked to better heart health and longevity. But the benefits of coffee consumption may depend on when you drink it, new research has found.

Reducing coffee consumption in the morning, it turns out, may be very good – and that appears regardless of the amount consumed and other factors that may have an effect, according to a study published on Tuesday in the European Heart Journal.

“This is the first study to examine patterns of coffee drinking time and health outcomes,” said lead author Dr. Lu Qi, Honorary Chair of the HCA Regents and professor at Tulane University’s Celia Scott Weatherhead School of Public Health and Tropical Medicine in New Orleans, in the news. release. “Normally we don’t give advice about timing in our food guide, but maybe we should think about this next time.”

Most previous studies investigating participants’ coffee intake over time have found that moderate levels of coffee consumption may be associated with lower risks of type 2 diabetes, heart disease and premature death, according to a recent study. But scientific evidence that factors such as genetics, amount eaten or added sweeteners affect this relationship is inconsistent or, at times, controversial, the authors say.

The authors studied dietary and health data on 40,725 adults aged 18 and older from the National Health and Nutrition Examination Survey conducted from 1999 to 2018. During 10 cycles over the years, the participants provided details of their diet from the previous day. The authors also included a subgroup of 1,463 adults, from both the female and male versions of the Lifestyle Validation Study, who had completed at least a one-week food record.

Both caffeinated and decaffeinated coffee were included, and time was divided into three periods: morning (from 4 am to 11:59 am), afternoon (from 12:00 pm to 4:59 pm) and evening ( from 5pm to 3:59am.

The researchers identified two patterns of time use: morning and daily. At the end of a median follow-up period of nearly 10 years, there were 4,295 deaths from all causes, 1,268 from cardiovascular disease and 934 from cancer.

Compared to people who did not drink coffee, drinking coffee only in the morning was associated with a 16% lower risk of premature death from any cause and a 31% lower risk of death from cardiovascular disease. Those who regularly drank coffee throughout the day did not have a reduced risk. These findings remained even after the authors took into account confounders such as hours of sleep, age, race, ethnicity, gender, family income, education, physical activity levels, food scores, and health conditions such as diabetes, high blood pressure and high cholesterol.

For people who drink coffee in the morning, the amount of caffeinated or decaffeinated coffee does not matter, either – whether they drink less than one or more than three cups of coffee a day. Doing so in the morning was still better than other patterns in terms of risk of death.

“This study was observational, which means it wasn’t a screening program, (which is the gold standard),” said Vanessa King, a registered dietitian and spokeswoman for the Academy of Nutrition and Dietetics who was not involved in the study. , by email.

The nature of the study also means that it only establishes an association, not a causal relationship between drinking coffee in the morning and the risk of premature death. But the findings are “significant since the leading cause of death in America is heart disease,” King said.

Why time is not important

Dr. David Kao, who was not involved in the research, found the study “fascinating” and one of the best investigations on the topic in years, he said.

“Highlights include using a machine learning style approach to categorize coffee drinking patterns, and validating findings from an external data source (more than one) different from the primary source, which greatly reduces the chances of false/false findings,” Kao, Jacqueline Marie Schauble Leaffer Endowed Chair in Cardiovascular Health of Women at the University of Colorado Anschutz, said in an email.

However, the study has several other flaws: In some cases, food recall is subject to inaccuracy or bias, and does not account for long-term trends, the authors say.

Second, although the authors considered many confounders, there may have been some that could not be completely excluded, they said – such as variations in work shifts and wake-up times.

The team also “could not rule out the possibility that a morning-type coffee drinking pattern is indicative of a healthier lifestyle,” according to the study. “For example, morning coffee drinkers may be more willing to exercise and eat less processed foods.”

Additionally, genetic information was not available, so the authors were unable to assess any potential effect of genetically determined caffeine levels.

A possible explanation for the findings “is that consuming coffee in the afternoon or evening may disrupt the circadian rhythm and levels of hormones such as melatonin,” Qi said. Low levels of melatonin have been linked to higher levels of blood pressure and oxidative stress, as well as a higher risk of heart disease.

Coffee also contains antioxidants that reduce inflammation in the body by removing free radicals that can increase the risk of heart disease, King said. Free radicals, unstable molecules from environmental sources such as cigarette smoke or pesticides, can damage cells.

Some markers of inflammation in the blood have their own clocks, say the authors, and are usually highest in the morning – so “the anti-inflammatory effect of a pattern of concentrated coffee consumption in the morning may be more beneficial than that of a pattern. … spread out in the morning, afternoon and evening.” That applies to both caffeinated and decaf coffee consumption.

Preparing the coffee meal

If you want to start limiting your coffee intake until the morning but you’re having trouble, think about whether you’re always getting enough quality rest, says King. Seeing a sleep specialist to determine if you have a condition, such as apnea, that interferes with your rest can also be helpful, Kao said.

You can also start by diluting your lunch and go with some water to hydrate, says King — which can help you feel more awake.

READ MORE: 6 ways to wake up without coffee

Checking your thyroid, vitamin D and iron levels can help you determine if fatigue is caused by something more serious, says Sue-Ellen Anderson-Haynes, a registered dietitian and spokeswoman for the Academy of Nutrition and Dietetics.

If you don’t drink coffee and think you could benefit from adding it to your routine, first “look at the big picture,” says Anderson-Haynes, who was not involved in the study. “Are you living a healthy, balanced, sustainable and healthy diet and lifestyle?”

Until more evidence is provided about when to drink coffee, he adds, follow your doctor’s or dietitian’s recommendation for caffeinated foods.

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