Dark roast doesn’t just lend a more broody, smoky flavor to your coffee cup — it can also potentially prevent stomach distress and exposure to a potentially harmful chemical. But these perks may not have a noticeable effect on all (or many) drinkers.
Easier on Sensitive Stomachs
“Darker roasts of coffee have been studied to contain less-acidic compounds, so someone with acid reflux may be less likely to react to dark roasts in contrast to light roasts,” Hall says.
The longer roasting process breaks down more acids in the beans, though darker roasts still contain some acid.
“However, the risk of reflux would not be completely eliminated by choosing dark roast coffee,” Hall adds. Other factors like caffeine content, large quantities, and whether it’s piping hot when you drink it can also contribute to reflux symptoms.
To reduce acid reflux from your coffee, opt for darker roasts, espressos (typically made with darker roasts), or cold brew coffee (where the process and the temperature help to reduce acids).
Lower in Acrylamide
Acrylamide is a chemical that naturally forms early on in the roasting process, but breaks down as roasting continues. It’s also found in food cooked at high temperatures. High levels of acrylamide have been linked to cancer in animals, but the human evidence is not conclusive. Still, health organizations recommend reducing your intake as a precaution when possible.
According to one study, light roast coffee has the most acrylamide, with 0.41 milligrams (mg) in every 100 grams (g). Medium roast had the lowest amounts, at 0.31 mg per 100 g.
“For the amounts in a cup of coffee, the acrylamide levels are within the range of what you’d expect of any commonly roasted food, such as french fries and chips,” says Bryan Quoc Le, PhD, a food scientist, lecturer of sustainable culinary practices at Unity Environmental University, and the founder of Mendocino Food Consulting in Mendocino, California. “It’s not expected to be harmful to the average consumer.”