Coffee is one of the most widely consumed beverages in the world, prized for its ability to boost energy and sharpen focus. But for some people, that morning cup can come with an unwelcome side effect: anxiety. Health experts say the connection between coffee and anxious feelings largely comes down to caffeine, the stimulant found in coffee. Caffeine activates the central nervous system, increasing alertness but also triggering the body’s stress response — which can mimic the physical sensations of anxiety such as a racing heart, restlessness, and nervousness.

One reason coffee can make some people feel anxious is how caffeine affects brain chemistry. It blocks adenosine, a neurotransmitter that normally promotes relaxation and sleepiness. When adenosine is blocked, the brain becomes more alert and releases stimulating chemicals like dopamine and norepinephrine. At the same time, caffeine can increase stress hormones such as cortisol and adrenaline, activating the body’s “fight-or-flight” response. This heightened state of arousal may feel similar to anxiety or even trigger panic symptoms in sensitive individuals.

The amount of caffeine you consume also plays a major role. Health authorities generally consider up to about 400 milligrams of caffeine per day—roughly four cups of coffee—safe for most healthy adults. However, consuming more than this amount may increase the likelihood of anxiety, sleep problems, and jitteriness. People who already struggle with anxiety disorders may be particularly sensitive, as caffeine can amplify symptoms like increased heart rate or nervousness.

Interestingly, not everyone experiences anxiety from coffee. Genetics, tolerance, metabolism, and overall health can all influence how the body responds to caffeine. Some people metabolize caffeine quickly and experience few side effects, while others process it slowly, allowing the stimulant to stay in the bloodstream longer and intensify its effects. Regular coffee drinkers may also develop a degree of tolerance over time, which can reduce caffeine’s anxiety-inducing impact.

Experts say that if coffee makes you feel anxious, you don’t necessarily have to quit it completely. Instead, simple adjustments can help. Try limiting caffeine intake, avoiding coffee on an empty stomach, switching to smaller servings or decaf, and avoiding caffeine late in the day to protect sleep. Paying attention to how your body responds is key. For many people, moderate coffee consumption can still be enjoyed without triggering anxiety—provided it’s consumed mindfully.

Bottom line: Coffee doesn’t automatically cause anxiety for everyone, but its caffeine content can increase anxious feelings in some individuals—especially at high doses or in people already prone to anxiety. Moderation and self-awareness are the best strategies for enjoying coffee without the jitters.