“Who knows whether it’s good for us or bad for us? You can find evidence either way!” This is a common complaint when we’re trying to figure out what lifestyle choices to make, and a common excuse for doing what we want in spite of the evidence. In many cases, it’s just an excuse — we know vegetables and exercise are good for us while soda and cigarettes are not — but coffee is a case in which the research seems to be divided. So is coffee good for your health, or not?
Research on coffee
Coffee has been thoroughly researched. However, George Zaidan in his book Ingredients: The Strange Chemistry of What We Put in Us and on Us points out that research about coffee has a very special characteristic. Much of the research was done at a time when a cup of coffee was frequently paired with a cigarette. As recently as 2014, coffee and cigarettes were strongly associated; in the 20th century, research on the health effects of coffee typically ignored the fact that most coffee drinkers had a cigarette with every cup. This skewed a lot of research results.
More recent research on coffee often focused only on caffeine, and not on the many other substances in coffee. The frequent association of sugar and coffee is important, and many studies of coffee did not include decaffeinated versions of the beverage.
There are also many different kinds of coffee, and they may have different effects. For example, some studies have found that coffee might contribute to high cholesterol. However, this seems to be true only for unfiltered coffee. If you make your morning java in a French press, you’re drinking unfiltered coffee, but most Americans use coffee filters.
So we have to be cautious about accepting statements on the health benefits of coffee without looking more closely at the evidence.
Caffeine
Caffeine is a natural stimulant. It is available in tea, energy drinks, and soda, but coffee is still the main source of caffeine for Americans. 90% of us drink at least one caffeinated beverage a day.
Caffeine blocks sleep-inducing adenosine in the brain, increasing the effects of dopamine and norepinephrine, which are mood-boosting substances. The effect is more energy and a better mood.
It can also increase performance in exercise, making you feel less tired. If this helps you get more exercise, that can improve your health.
Caffeine consumption may also reduce stroke, heart disease, and Type 2 diabetes.
On the other hand, too much caffeine can cause some people to feel jittery or to have trouble sleeping. Too much coffee can cause heartburn or other digestive issues, too. There is also some indication that caffeine can affect calcium absorption in bones. While the evidence suggests that this is not a problem for adults who have a sufficient intake of calcium, it could be a good reason for children to avoid caffeine.
As for the negative effects of caffeine, it seems that some individuals are more sensitive to caffeine than others. This may be genetic. If you feel bad when you drink coffee or other caffeinated drinks, cut back or switch to decaf.
Aside from caffeine
Caffeine is just a small part of what’s in coffee. Coffee also contains antioxidants and even vitamins and minerals, just as most plant foods and drinks do. Broccoli has lots more nutrition than coffee, but most of us take in lots more coffee than broccoli. In fact, coffee is one of the top sources of antioxidants for most American adults.
Researchers think that this may be why coffee is associated with lower rates of liver disease, Parkinson’s disease, and some cancers.
Decaffeinated coffee can be a healthy choice. And extensive research suggests that one or two cups of caffeinated coffee a day is not harmful, and may be beneficial.
However, there is a big difference between a cup of black coffee and a Frozen Caramel Latte. If you add sugar or creamers to your coffee, you have to consider the health consequences of those ingredients as well.