For centuries, people have reached for a cup of coffee to help focus the mind, but according to a study published in 2021, a morning cup of java could have the opposite effect.

Researchers recruited 32 habitual coffee drinkers and 24 non-coffee drinkers and asked them to complete questionnaires used to measure stress, anxiety, and depression. Each participant then underwent a resting-state functional MRI scan that measured connectivity in various parts of the brain.

The coffee drinker group exhibited decreased functional connectivity in two important networks: the somatosensory, which processes sensations like pressure, pain, or warmth; and the limbic, which is involved in emotional responses and memory formation, among other things.  The coffee drinkers also had decreased connectivity in the subcortical and posterior brain regions, which include motor and emotional processing as well as the visual network and the cerebellum.

Among the coffee drinkers, the researchers identified a clear association between coffee consumption frequency and reduced connectivity— the more coffee one drank, the less connectivity they had in these areas of the brain. The coffee drinkers also had elevated stress and anxiety levels, which were even higher in the heaviest coffee drinkers.

In the second phase of the experiment, researchers asked the non-coffee drinkers to drink a cup of coffee and then imaged their brains for a second time. The post-coffee scan showed altered activity in the same areas of the brain, which suggests that coffee itself is more likely to be responsible for the reduced brain connectivity, rather than individuals with reduced connectivity being more likely to desire coffee.

So, is coffee bad for you? This is just one study, and the findings may not be reproducible in another group or the data could be interpreted in another manner. That’s why researchers do follow-up studies with larger groups and more variables. Over time, as research grows on a particular topic, more scientists will conduct meta-analyses to try and come to firmer conclusions that may make their way into lifestyle recommendations or treatment guidelines.

On the other hand, there is a lot of research that drinking up to 3.5 cups of coffee a day may be associated with reduced risk for cardiovascular disease, death from cardiovascular disease, early death, and a lower risk for some cancers and conditions that affect metabolic health and liver function.

Time will tell if coffee is more bad than good for you, but the present data suggests it’s most likely beneficial, and if you enjoy the beverage, do so in moderation. And if you have aches and pains that are interfering with your ability to get into the kitchen to make a cup or to walk to a nearby coffee shop, then make an appointment with your doctor of chiropractic to see if a short-term course of treatment might help resume your normal activities.