Study shows limiting coffee drinking to this time may reduce risk of premature death

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Drinking coffee has repeatedly been linked to improved heart health and longer life. But new research finds that the benefits of drinking coffee may depend on when you drink it.

It turns out that limiting coffee intake to the morning may be best, and it doesn’t appear to be related to the amount consumed and other potentially influencing factors, according to a study published Tuesday in the European Heart Journal.

“This is the first study to test temporal patterns of coffee drinking and health outcomes,” lead author Lu Qi, PhD, HCA Regents Distinguished Chair and professor at the Celia Scott Weatherhead School of Public Health and Tropical Medicine at Tulane University in New Orleans, said in the news release. “We don’t usually provide advice on timing in dietary guidance, but perhaps we should consider this in the future.”

Most past studies examining participants’ coffee intake over time have found that moderate coffee intake may be associated with a lower risk of type 2 diabetes, cardiovascular disease and premature death, according to new research. But scientific evidence on whether factors such as genetics, intake or added sweeteners influence these relationships has been inconsistent and sometimes controversial, the authors said.

The authors studied diet and health data on 40,725 adults aged 18 and older from the National Health and Nutrition Examination Survey conducted from 1999 to 2018. Quantity details. The authors also included a subgroup of 1,463 adults from the female and male versions of the lifestyle validation study who completed at least one week of dietary records.

Both caffeinated and decaffeinated coffee are included, and the times are divided into three time periods: morning (4 a.m. to 11:59 a.m.), afternoon (12 noon to 4:59 p.m.) and evening (5 p.m. to 3:59 a.m.) ).

The researchers identified two consumption time patterns: morning and throughout the day. By the end of the nearly 10-year median follow-up period, a total of 4,295 people had died from all causes, including 1,268 from cardiovascular disease and 934 from cancer.

Compared with non-drinkers, people who drank coffee only in the morning had a 16% lower risk of dying prematurely from any cause and a 31% lower risk of dying from cardiovascular disease. Those who tended to drink coffee throughout the day were not at reduced risk. These findings persisted even after the authors took into account confounding factors such as sleep duration, age, race, ethnicity, gender, household income, education, physical activity levels, diet scores, and health conditions such as diabetes, high blood pressure, and high cholesterol.

For morning coffee drinkers, it doesn’t matter how much caffeinated or decaffeinated coffee they drink—whether they drink less than one cup or more than three cups a day. In terms of risk of death, doing it in the morning is still better than other modes.

“This study was observational, which means it was not an experimental setting, which is the gold standard,” said Vanessa King, a registered dietitian and spokesperson for the Academy of Nutrition and Dietetics, who was not involved this research.

The nature of the study also means it only established an association between morning coffee drinking and risk of premature death, not causation. But King added that the findings “are significant because the leading cause of death in the United States is cardiovascular disease.”

Why timing is important

Dr. David Kao, who was not involved in the study, said the study was “fascinating” and one of the best studies on the subject in years.

“Highlights include using a machine learning-style approach to classify coffee drinking patterns and validating findings from (multiple) external data sources that are distinct from the primary source, which greatly reduces the likelihood of accidental/false positive findings,” University of Colorado Gao, the Jacqueline Marie Schäuble-Lever Endowed Chair in Women’s Heart Health at Anschutz, said via email.

However, the study had several other shortcomings: First, memories of dietary intake may be inaccurate or biased, and they did not take into account long-term habits, the authors said.

Second, although the authors considered multiple confounding factors, they said there may be other factors that cannot be completely ruled out, such as changes in work shifts and wake-up times.

The team also “cannot rule out the possibility that morning coffee drinking patterns are a marker of an overall healthy lifestyle,” according to the study. “For example, people who drink coffee in the morning may be more likely to exercise and eat non-ultra-processed foods.”

Additionally, the authors were unable to examine any possible effects of genetically determined caffeine metabolic rates because genetic information was not available.

One possible explanation for the finding is that “drinking coffee in the afternoon or evening may disrupt circadian rhythms and hormone levels such as melatonin,” Qi said. Low melatonin levels are associated with increased blood pressure, increased levels of oxidative stress, and increased risk of cardiovascular disease.

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

The authors say that some inflammatory markers in the blood have their own clocks and are typically highest in the morning, so “the anti-inflammatory effects of a morning coffee-focused pattern may be more beneficial than a morning coffee-focused pattern.” … .Distributed in the morning, afternoon and evening. This applies to the consumption of caffeinated and decaffeinated coffee.

Adjust coffee intake

If you want to start limiting your coffee intake in the morning but are having trouble, consider whether you’re getting enough quality rest on a regular basis, King says. It may also be helpful to see a sleep specialist to find out if you have a condition like sleep apnea that interferes with your rest, Gao said.

You can also start by diluting your daytime meals and hydrating with water, which can also help you feel more alert, King says.

Read more: 6 Ways to Wake Up Without Coffee

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

If you don’t drink coffee and think you could benefit from adding it to your daily routine, first “look at the big picture,” said Anderson-Haines, who was not involved in the study. “Is your diet and lifestyle generally active, balanced, sustainable and healthy?”

She added that until more evidence is provided about when to drink coffee, follow your doctor or nutritionist’s advice on caffeine intake.

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