When it comes to iced versus hot coffee, conversations usually focus on personal taste. But what about health? Do the two versions of coffee affect the human body differently, and are the differences stark enough to warrant permanent changes in your caffeine consumption?
To find out, HuffPost spoke with Dr. Majid Basit, a cardiologist with Memorial Hermann in Sugar Land, Texas.
Basit said there isn’t much research on the subject, but he did note one difference: “Hot coffee has been shown to have higher amounts of antioxidants, which may offer health advantages. But more research needs to be done,” he added.
A 2018 study in Scientific Reports bears that out. Researchers from Thomas Jefferson University found that hot coffee has higher levels of antioxidants, which can prevent or slow damage to cells, compared to cold brew.
But what if you’re looking to get an extra boost of caffeine? That’s when things get tricky. Caffeine is extremely variable in brewed coffee and depends on a variety of factors, including the beans used.
Though a 2020 study by the American Chemical Society found that hot brewing methods yield slightly higher caffeine levels than cold brew methods, it’s important to note that the differences were not big enough to overcome the variables mentioned above. So in general, you’ll get a solid dose of caffeine whether you drink your coffee hot or cold.
“Caffeine has both positive and negative effects on the body,” Basit explains. “It increases brain alertness and general energy levels, but will also increase the acid in the stomach leading to an upset stomach in some people.” The cardiologist also mentioned increased urination, blood pressure and heart rate, along with a decrease in the body’s ability to absorb calcium, which may lead to lower bone density.
To recap: an average cup of hot coffee boasts slightly more antioxidants and approximately the same amount of caffeine as its colder counterpart. Overall, studies have not revealed major differences in how the human body reacts to the two forms of java. Hot or cold, coffee seems to generally be good for you.
According to a 2017 study by the University of Colorado, drinking coffee weekly can help reduce one’s chances of getting a heart attack by as much as 7%. And a series of three 2022 studies that were presented at the American College of Cardiology’s 71 Annual Scientific Session further support that coffee is good for heart health.
There is, however, one characteristic of a warm cup of joe that majorly differentiates it from a cold brew, and it doesn’t have anything to do with consumption: the smell of hot coffee.
According to a 2008 study published in the Journal of Agricultural and Food Chemistry, there is a connection between bean aroma and “potential antioxidant or stress relaxation activities.”
Using rats in a lab experiment, researchers found that a single whiff of hot coffee was enough to reduce tiredness and stress levels. “Since hot coffee has more vapours emanating from it, it is possible this effect may be heightened with hot coffee versus cold coffee,” Basit says.
The cardiologist does, however, also make it a point to note that there is no definitive research on the topic and that a lot of the results might be connected to a placebo effect.
Turns out, then, that the battle between hot vs. cold brew is one still worth arguing about.