How Caffeine and Alcohol Affect Your Heart Rate

An elevated heart rate may often signify a heart or other condition. But certain drinks can also cause a temporary increase in your heart rate, depending on your age, how physically active you are, stress and the medications you take.

Your heart rate, also called your pulse, is the amount of times your heart beats each minute, according to the American Heart Association (AHA). What's considered a normal heart rate can vary from person to person, but it's important to know yours so that you can gauge the health of your heart.

Your resting heart rate is when your heart is pumping the smallest quantity of blood you need because you are in a relaxed, calm state, explains the AHA. This heart rate is typically 60 to 100 beats a minute. If you're very physically active, you may have a resting heart rate as low as 40 beats a minute, says the AHA, because the muscles in your heart are in better shape and don't need to work as hard to maintain a steady beat.

To check your heart rate, the AHA suggests you to put your finger over certain places on your body — your wrists, the side of your neck, inside of your elbow or the top of your foot — for 60 seconds and count the number of beats.

Read more: My Heart Rate Rises With Light Activity

You may notice your heart pounding a bit more after drinking alcohol. Drinking in moderation is key, says the AHA, which means no more than two drinks a day for men and one for women. Conversely, men who consume five-plus drinks in two hours or women taking in four or more is considered binge drinking, says AHA, which cannot only cause an irregular heartbeat but can lead to such complications as stroke, blood clots and heart failure.

"Alcohol is dehydrating, meaning it reduces your blood volume, which also increases heart rate," says Jen Lyman, RD, a dietitian and founder of New Leaf Nutrition, in the greater St. Louis area. The AHA also notes that heavy drinking can cause arteries to age quickly, which could lead to atrial fibrillation or an irregular heartbeat.

A study published in the European Heart Journal in July 2017 analyzed more than 3,000 people who attended the 2015 Munich Octoberfest to find if alcohol consumption was associated with cardiac arrhythmias. Based on electrocardiogram readings and breath alcohol concentrations, the researchers found that, as breath alcohol concentration increased, heart rate also increased more than 100 beats a minute in nearly 26 percent of the participants.

Read more: What Really Happens to Your Body When You Stop Drinking Alcohol

Caffeine can be found in beverages such as coffee, tea, soft drinks and energy drinks. Consuming these stimulates the central nervous system, which gives you an energetic boost and increased alertness, according to the U.S. National Library of Medicine (NLM). But, caffeine can also temporarily raise your heart rate and blood pressure, which can be dangerous, the NLM adds.

Some people are more sensitive to caffeine than others, according to the NLM, adding that those who are pregnant or breastfeeding or have such conditions as migraines, sleep disorders, GERD or hypertension or take certain meds may need to limit caffeine intake or avoid it altogether.

A small study published in the International Journal of Physiology in July 2019 evaluated the effects that energy drinks had on the blood pressure and heart rate of 40 study participants. One hour after consuming the energy drink, the participants had their blood drawn, with the results showing that their heart rate increased significantly from what it had been before they drank the energy drink.

Read more: What Really Happens to Your Body When You Have Caffeine

For most healthy adults, about 400 milligrams of caffeine (or about four cups of brewed coffee) daily seems to be safe, according to the Mayo Clinic. Consuming higher amounts of caffeine, can lead to such side effects as a fast heartbeat, nervousness, headache or insomnia.

Choosing drinks that contain lower levels of caffeine should help avoid a spike in your heart rate. "Drinks that can slow heart rate would be things like chamomile or kava tea because they're calming and soothing," says Lyman.