According to the Centers for Disease Control and Prevention (CDC), about 8 in 10 adults consume caffeine daily. If you’re a regular caffeine consumer, you have likely experienced the jittery feeling you get when you drink too much and may wonder what other side effects caffeine can cause beyond the short-term energy boost.
We Know What Caffeine Does, but What Is It?
Caffeine is a stimulant, a type of drug that enhances your body’s reactions and response systems, including your central nervous system, which regulates your heartbeat. That’s why if you drink too much coffee at one time, you may feel your heart beating faster.
It takes about 30 minutes for caffeine’s effects to kick in and then 5-6 hours to wear off. This duration means that your heart rate is also affected for roughly the same length of time. Along with a faster heart rate, you may experience heart palpitations, which feel like your heart is racing, pounding in your chest or skipping a beat. These side effects are often temporary for healthy adults and don’t cause long-lasting damage. However, if you have heart disease or a heart rhythm disorder, it’s a good idea to bring these palpitations to your doctor’s attention.
A Few Cups of Coffee Can Be Good for Your Heart
It’s worth monitoring any substance that affects your heart rate. But, with a bit of care, we can still enjoy the benefits of consuming caffeine. Caffeine even has a few heart-healthy benefits, particularly if it comes from coffee.
Research published in the European Journal of Preventive Cardiology found that drinking two or three cups of coffee a day can reduce your risk of heart disease and heart rhythm disorders. The type of coffee didn’t seem to matter. Ground and instant coffee both protected participants’ hearts and caffeinated coffee was found to provide more protection than decaf. The authors did note, however, that some of this protection may have come from the many other compounds in coffee besides caffeine.
There is an exception to these findings. If you have high blood pressure, avoid caffeinated coffee. Instead of possibly providing heart-related benefits, caffeine may increase your risk of heart attack or stroke.
How Much Caffeine Is Too Much?
Most adults can safely consume 400 milligrams of caffeine daily. Consuming more can cause negative symptoms, including anxiety, heart palpitations and headaches. In general, coffee has about twice the amount of caffeine as tea, but the amount varies.
- An 8-oz cup of brewed coffee has around 100 milligrams.
- One espresso has 64 milligrams.
- An 8-oz instant coffee has about 60 milligrams.
- An 8-oz cup of brewed black tea has about 50 milligrams.
- An 8-oz cup of brewed green tea has about 30 milligrams.
- White tea and herbal teas are generally caffeine-free.
- Ready-to-drink bottled tea has about 20 milligrams.
- An 8-oz glass of cola has about 20 milligrams.
- Citrus and root beer sodas are generally caffeine-free.
- An 8-oz energy drink has about 72 milligrams.
- A 2-oz energy shot has 215 milligrams.
When Too Much Caffeine Is Bad for Your Heart
Though caffeine in coffee may be beneficial to heart health, overconsumption of caffeine in other forms could be harmful. In recent years, drink manufacturers have overloaded energy drinks and other beverages with extremely high levels of caffeine. The Centers for Disease Control and Prevention warns that these “extra-strength caffeinated products” may generate severe disturbances in the nervous system and heart.
If you experience negative symptoms from drinking too much caffeine, simply reduce your intake. If heart palpitations or other side effects persist even after reducing or eliminating caffeine from your diet, contact your primary care provider and schedule an appointment.
People begin to experience extreme reactions, such as seizures, to caffeine when doses exceed 1,200 milligrams, according to the FDA. Those doses usually come from concentrated caffeine found in powders and supplements. To put that in perspective, they explain that one teaspoon of concentrated caffeine is equal to 28 cups of coffee. That’s more than the average person drinks in an entire week.
Going Beyond Coffee
In moderation, caffeine is not bad for your heart. Although coffee is one of the most common sources of this energy booster, you can find it in other foods and drinks, some of which have their own heart-health benefits.
If you’d like some caffeine but don’t drink coffee, you can find it in the following:
- Chocolate. Cocoa, a main ingredient in chocolate, contains caffeine. The amount of caffeine in chocolate depends on how much cocoa it contains—dark chocolate (which has more cocoa) has higher levels than milk chocolate (which has less). Dark chocolate is also high in antioxidants that can protect against heart disease. According to the USDA, one tablespoon of cocoa solids contains 12 milligrams of caffeine.
- Tea. When not topped off with sugar, tea is a healthy caffeine source. Sip on this drink to get some important minerals (potassium, zinc, copper and more) and possibly reduce your heart disease risk in the process.
While water is always the best choice when you’re thirsty, if you’re feeling a little energy slump in the late morning or early afternoon, going for a caffeinated drink is fine. Just remember to avoid overdoing it and skip caffeinated beverages loaded with added sugar.
More to Read
- Tired? Having Headaches? You Could Be Experiencing Caffeine Withdrawal
- How Eating Added Sugar Puts You at Higher Risk for Health Issues
- Top Reasons Sugar Alcohols May Not Be a Good Sugar Substitute
- Avoiding Dehydration When You Have Heart Failure
- Is There Such a Thing as a Healthy Sports Drink?
Medically reviewed by Jessika Rose RD, LDN, Bariatric Dietitian at UM Upper Chesapeake Bariatrics Program
