These Are the #1 Signs You’ve Had Too Much Coffee, According to… Your Body

For some, drinking cup after cup of coffee has virtually zero effect: They can easily take a nap moments after chugging a post-meal cappuccino. But for others, just a few sips of java can send them spiraling into an uncomfortable, caffeine-induced jittery state.

Although the FDA recommends consuming no more than 400 milligrams of caffeine per day—about four to five eight-ounce cups of coffee (which is quite a lot)—the threshold for caffeine tolerance can vastly vary from person to person. So, how can we really tell what’s the maximum amount of coffee we should be drinking based on our individual needs?

According to Caroline Cederquist, MD, a board-certified physician and founder and chief medical officer of BistroMD, it starts with listening to your body. We caught up with Dr. Cederquist to spot the signs that your body is telling you that you’ve had too much caffeine and how caffeine overload can affect the quality of your sleep.

How your body is telling you that you’re drinking too much coffee

For starters, Dr. Cederquist explains that the definition of “too much” coffee can drastically vary based on the individual due to caffeine sensitivities and intolerances. “One person might comfortably drink a few cups, while another might experience side effects after a single cup,” Dr. Cederquist says.

However, there are clear signs that your body has had too much caffeine. This includes symptoms like: feeling jittery, irritable, nauseous, restless, and anxious. “Headaches, a fast heartbeat, and frequent urination are also telling signs you’re drinking too much coffee,” Dr. Cederquist says. In order to stave away these uncomfortable side effects, including inflammation, Dr. Cederquist recommends sticking to the FDA guidelines or consulting with your doctor to determine what’s best for you, as well as judging your tolerance based on how your body reacts to caffeine.

“Headaches, a fast heartbeat, and frequent urination are also telling signs you’re drinking too much coffee,” Dr. Cederquist says.

It’s also worth noting that caffeine can interact with certain medications or preexisting health conditions. “There’s a wide range of medications that can interact with caffeine, like antiseizure, anticoagulant, and antidepressant medications, just to name a few. If you’re taking any sort of medication, it’s essential you review potential interactions with your doctor and/or pharmacist,” Dr. Cederquist says.

However, if you’re highly caffeine-sensitive, Dr. Cederquist suggests finding ways to cut back on consumption to avoid overloading in the first place is the best thing to do. “If you’re an avid coffee drinker, this can feel daunting, but you can take actionable steps to do so more effortlessly. The first step is cutting back on caffeine slowly and gradually, which could be going from five cups of coffee per day down to four cups for a week until you’ve reached your personal goal,” she says.

But if you enjoy sipping on something while you work during the day or simply love the taste of coffee, decaf can be a great alternative solution. “You could also swap out a caffeinated cup of coffee for decaf. That way, you can still enjoy the warmth and flavor of coffee, just without all the excess caffeine,” Dr. Cederquist says.

How drinking too much coffee impacts your sleep

Although we hate to hear it, coffee can definitely impact our ability to get restful sleep. “Caffeine is a stimulant and blocks adenosine, which is a naturally occurring chemical in the body that helps the body relax and promotes sleep,” Dr. Cederquist says. Although reducing sleepiness, increasing focus, and boosting energy may be reasons folks drink coffee in the first place, Dr. Cederquist confirms that it can impact sleep, especially if consumed too close to bedtime.

“Caffeine has about a five-hour half-life, meaning if you drink a cup of coffee in the early evening, you’ll still have half of the caffeine in your system once it’s time for bed,” Dr. Cederquist says.

“Caffeine has about a five-hour half-life, meaning if you drink a cup of coffee in the early evening, you’ll still have half of the caffeine in your system once it’s time for bed,” Dr. Cederquist says. To ensure you can have your coffee and get a good night’s rest, too, she recommends sticking to a caffeine consumption schedule that won’t interfere with your nighttime routine. “To enjoy your coffee while still getting a restful night’s sleep, it’s important to try to stick to coffee during the morning and very early afternoon hours while monitoring how much you consume.”

A registered dietitian shares some of the benefits of drinking coffee: