Do you take your coffee with milk or sugar? One’s coffee order might have an effect on long-term health, according to a study published in May in the journal Annals of Internal Medicine.
Coffee is an incredibly popular daily beverage. One survey found that 66 percent of Americans had at least some coffee in the past day, and the average joe-drinker has more than three cups of the stuff daily. So studying its effects on our health is important.
Science in action — The researchers from Southern Medical University in Guangzhou, China analyzed data from 171,616 people, all retrieved from U.K. Biobank, which stores oodles of demographic and health information from hundreds of thousands of participants.
The team tracked the data between 2009 and 2018 to see what they could glean about someone’s life from their coffee order. Specifically, they looked at healthy subjects without cardiovascular disease or cancer. That way, severe chronic diseases wouldn’t be potential influencers on health from the get-go. As they tracked the data, the researchers marked each death and labeled them as cancer-related, cardiovascular-related, or a death from some other cause.
Why it’s a hack — Researchers found that moderate coffee drinkers (that means decaf, too) showed the lowest risk for mortality. The researchers describe the trend between coffee and mortality risk as a U-shaped curve: Those who consume two to three cups of black or lightly sweetened (with an average of one teaspoon of sugar) coffee per day had the lowest risk of mortality — by up to 30 percent — and derived the most benefits from the drink.
The risk of mortality was highest on the two ends. One end represents those who drink zero coffee and the other end represents those who consume highly modified coffee (with lots of added sugar and dairy).
This study doesn’t necessarily say anything about the effects of artificial sweeteners. In fact, while the study concludes that moderate consumption of unsweetened and sugar-sweetened coffee links to a lower risk of death, the association between artificially sweetened coffee and mortality was “less consistent.” That doesn’t mean more people who drank frappuccinos died, but that no apparent trend emerged.
Speaking of trends, the researchers also acknowledge the importance of not immediately ascribing causality. Neil Murphy, a nutrition and metabolism scientist with the International Agency for Research on Cancer who was not involved in the research, agrees. “[Whether] these associations are causal is unknown and the biological mechanisms underlying these relationships are not well understood,” Murphy wrote to Inverse in an email.
Another trend that Murphy noticed: “Sugar-sweetened coffee consumers were more likely to be male, from a lower social class, and current smokers and generally had less healthy diets.” Some qualities associated with black coffee drinkers were “a higher social class and generally…healthier diets.” In their analysis, the authors adjusted for these factors as much as possible, but it’s impossible to have bias-free data.
How this affects longevity — Coffee oscillates in status as healthy or not. Following this particular research, the hot bean juice seems to be firmly in our good graces. And there’s other evidence that it’s good for us, too, and could even help us live longer, healthier lives.
Ali Rezaie, a gastroenterologist at Cedars-Sinai Medical Center who was also not involved in the current research, says that coffee is great for that teeming, tiny zoo inside us all, the gut microbiome. “There is no question that coffee and caffeine as a stimulant, improves the gut microbiome,” Rezaie tells Inverse.
For many people, coffee boosts gut motility (i.e., it makes you poop) because it triggers the gastrocolic reflex that tells your large intestine to clear out, and it stimulates production of the hormone gastrin, which helps create stomach acid. Staying regular and flushing out old food is a great way to get rid of bacteria you don’t need anymore in your colon. There are consequences if they don’t get pushed out.
“When the small bowel is not moving well, then the colonic bacteria in the large bowel start to creep back up into the small bowel,” Rezaie says. For one thing, those creeping colonic bacteria are now poaching some of the nutrients from the food you eat, and if you’re eating a lot of sugar then they’re multiplying like single-celled rabbits. This phenomenon is called small intestinal bacterial overgrowth, or S.I.B.O.
Coffee also brims with anti-oxidants, minerals, and organic plant compounds that are good for us. While we’re still not totally clear on all the mechanisms behind how coffee boosts our health, Rezaie says, we do know that regulating gut motility improves the microbiome. A healthy gut microbiome is a pillar of holistic health and longevity. Rezaie co-authored a 2021 paper that found as we age, the gut microbiome becomes less diverse. A different 2020 study that Rezaie was not part of found an association between regular coffee consumption and increased levels of three types of bacteria.
Too much sugar isn’t great for the gut. It goes into “hyperdrive,” Rezaie says, from a food’s high sugar content. While it normally takes about four hours to digest and empty proteins, carbohydrates move through the stomach in only about two hours. And that’s apart from excess sugar’s negative effects on the cardiovascular system. That’s why just a little bit of sugar in coffee, about a teaspoon, won’t ruin the health benefits of the beverage.
Hack score — ☕️️️️️️☕️☕️☕️☕️☕️☕️🥄/10 (seven cups of black coffee and one teaspoon of sugar)