Is Moderate Coffee Drinking Good for Your Health?

What do you like best about coffee?

For many of us, it’s the taste of our favorite traditional or trendy blend.

For others, it’s the lift that caffeine provides when we first roll out of bed or take a break at work.

But there may be something to like even more about coffee—its potential health benefits.

Recently, a study published by the European Journal of Preventive Cardiology linked drinking two to three cups of coffee a day with a longer lifespan and lower risk of cardiovascular disease compared with avoiding coffee. That’s just one of several studies that have emerged during the past several years suggesting that moderate coffee consumption may be good for your health.

The key word, however, is “may.”

Promising Signs
“Health benefits make sense intuitively because we know coffee beans contain a lot of antioxidants and phytonutrients, which are found in certain plants,” says Dr. Daniel A. Monti, founding director and CEO of the Marcus Institute of Integrative Health – Jefferson Health. “Plants sustain us; they contain substances that help us thrive, and the data that there could be potential health benefits in coffee has increased a lot in the past few years, but more information is needed,” he says.

“There have been a lot of studies on different correlations between coffee consumption and lowered risk of cardiovascular disease, cancer, diabetes and more,” says Dr. Niny Z. Rao, associate professor of chemistry. “The data is promising, but none have determined with 100% certainty the actual causation of that lower risk. Is it coffee alone or are there other contributing variables?”

Dr. Rao’s research interests lie in computational chemistry and the chemistry of artisanal food and beverages. Over the past several years, her focus has been on the impact of roasting and brewing on the chemical composition of coffee—particularly, the differences between hot and cold brews.

The Impact of Antioxidants
Take, for example, antioxidants, which are substances that may prevent or delay diseases. Coffee has a lot of antioxidants to begin with. Cooking coffee beans extracts additional antioxidants. Dr. Rao and research colleague Dr. Megan Fuller, assistant professor of chemistry, have determined that hot-brew coffee has higher levels of antioxidants than cold brew.

If you prefer cold brew, however, don’t go switching to hot for the sake of your health just yet.

“Assuming that all antioxidants in coffee are good for lowering risk of disease is a huge assumption,” Dr. Rao warns. “The jury is still out on that.”

Dr. Monti agrees with Dr. Rao.

“Much of the data presented so far that alludes to a positive effect of antioxidants in coffee is ‘epidemiologic’ data. It’s not produced by a study that looks at the mechanisms of action responsible for health outcomes in randomized participants,” he explains. “In addition, participants in some of these studies may only be getting their antioxidants from coffee, so the impact on them may be disproportionate to the effects on someone who gets a lot of nutrients through a plant-based diet. So, we’re not exactly sure what the antioxidants in coffee are doing. We are only guessing that they are responsible for some health benefits we may be seeing.”

Everything in Moderation
Dr. Monti adds that for those who don’t like the taste of coffee, there are other antioxidant-rich beverages for which there is encouraging data regarding health benefits—for example, green tea. But be mindful that green tea and decaffeinated coffee, as well regular brews, contain caffeine, which can exacerbate anxiety, sleep deprivation and high blood pressure.

Assuming your blood pressure is under control, there is very little harm likely to result if you restrict yourself to one to three cups of coffee a day—normal 8-ounce cups, not those trendy oversized models, Dr. Rao cautions.

A Drop in Acidity
Another fruit of Dr. Rao’s research with Dr. Fuller into the chemistry of coffee centers on acidity. The chemists found that dark roast coffee has a slightly lower acidity than medium and light roast, and that cold-brew coffee has a slightly lower acidity than hot brew, making cold-brewed dark roast coffee the least acidic of all.

“We think cold-brew coffee—especially a darker roast—may be a slightly better alternative for those who are sensitive to acidic food and for singers and other vocal professionals who want to minimize acid reflux and acid intake that may corrode the throat and the entire digestive system,” Dr. Rao says.

However, she adds, the difference in acidity between cold brew and hot brew is relatively small. If you prefer to drink hot brew, especially now that the weather is turning cooler, and want one that has a lower acidity, choose a darker roast. By diluting your coffee with the addition of a little more water during brewing, you’ll have even less acidity to worry about.

Speaking of the digestive system, Dr. Monti notes that there are also early studies that coffee might have some beneficial effects on the gut microbiome, which is important to good digestion and a healthy immune system. The jury is still out on this, however; additional, more carefully designed studies are needed.

Coffee on the Brain
The same holds true for findings about coffee’s possible positive impacts on brain health. Take, for example, a study published last November, which found that those who drank four to six cups of coffee a day, as well as tea, had a lower incidence of stroke and dementia. Unfortunately, the study couldn’t actually prove that beverage consumption was the actual cause of this lower risk. Neither could studies suggesting that coffee can reduce the risk of Alzheimer’s and Parkinson’s disease.

Such population-based studies look backward to see how many people in groups developed degenerative brain diseases such as Parkinson’s—their conclusions are based on coffee consumption that wasn’t observed and recorded first-hand by scientists as it happened, so the amount of coffee that study participants claimed to have drunk long-term may not be accurate.

To draw sounder conclusions about coffee’s impact on our brains, and on our bodies, Dr. Monti says, what’s needed is data gathered from studies that are more carefully designed and forward-thinking—that is, that accurately chronicle participants’ long-term daily coffee consumption and developments to their health as they happen in order to credibly determine if there is, indeed, a correlation. Further analysis of coffee’s chemical content is also required.

“Right now, we don’t really know whether there are actually any health benefits from drinking coffee,” Dr. Monti says. “There’s encouraging data that suggest there are, but the data is still being sifted. I’m cautiously optimistic that through the efforts of researchers like Dr. Rao, the research will keep moving in a positive direction.”

“Coffee has been around for hundreds of years,” Dr. Rao concludes. “But we’re still trying to understand exactly what’s in coffee and how it affects us. There are so many variables in coffee brewing, so we’re just scratching the surface.”