Do you love to wake up to the smell of your morning coffee brewing in the kitchen? The majority of people drink some form of a caffeinated beverage throughout the day, but you should be aware of the negative effects of caffeine. These include physiological effects, such as an elevated heart rate.
Read more: Your Brain on Coffee: A Conversation with Bulletproof Founder Dave Asprey
Caffeine Heart Rate
Caffeine is ever-present. According to a January 2014 report from Food and Chemical Toxicology, caffeine intakes have risen from more than a decade ago. Around 85 percent of people consume at least one caffeinated beverage per day, and 96 percent of beverage caffeine comes from coffee, soft drinks and cups of tea. But everyone who gives in to their caffeine addiction should stay familiar with the negative effects of caffeine to keep themselves healthy.
Once consumed, caffeine enters your blood from the stomach and small intestine and begins to stimulate your central nervous system. Caffeine stimulates receptors located in cells within your heart to increase your heart rate. Effects of this stimulation speed up your blood flow because of an increase in heart rate, which can accelerate by approximately three beats per minute (as well as cause an increase in blood sugar, urine production and body temperature).
The increase in your heart rate from caffeine consumption can take effect in as soon as 15 minutes and take approximately six hours to wear off, according to the University of Michigan Health Service. (You will eventually urinate out the caffeine.)
In an April 2019 review from Harvard Health Publishing, caffeine can pose a danger to those with heart disease because the drug can cause a temporary rise in heart rate and blood pressure. However, regularly consuming caffeinated beverages won't disrupt your heart's rhythm enough to create irregular heartbeat patterns.
Caffeine can also affect heart rate after you exercise. In a 2017 study from Scientific Reports, researchers studied the effects of heart rate and blood pressure recovery after aerobic exercise. They found that caffeine can delay the parasympathetic heart rate control, which allows the body to slow down the heart rate after exercise.
Other Negative Effects of Caffeine
Not only does caffeine affect heart rate, you can experience other negative effects, such as the following:
- The University Michigan Health Service says that large amounts of caffeine, about 1,000 milligrams per day, can lead to conception problems, heartburn and irregular bowel movements. Even smaller amounts can lead to sleep issues and a disregard of signals that your body desires sleep. This can cause a disturbance in energy levels, emotional fatigue and depression.
- According to Scientific Reports, too much caffeine can cause anxiety, headaches and restlessness.
- You can also have a caffeine overdose when ingesting high levels. An April 2018 warning from U.S. Food & Drug Administration (FDA) cautions consumers that consuming pure or highly concentrated caffeine can cause serious adverse events, including seizure and even death. In fact, the FDA is aware of at least two deaths related to caffeine overdoses in healthy individuals.
But overall, the way that you react to caffeine depends on your sensitivity, the source and how much you consume, according to Harvard Health Publishing. You should stay within the FDA's recommended limits of 400 milligrams per day for healthy adults. This amounts to 4 to 5 cups of coffee, which hasn't been found to cause any major health impairments to your heart rate.
- Food and Chemical Toxicology: “Beverage Caffeine Intakes in the U.S.”
- University of Michigan Health Service: “Caffeine”
- Scientific Reports: “Caffeine Affects Autonomic Control of Heart Rate and Blood Pressure Recovery After Aerobic Exercise in Young Adults: A Crossover Study”
- Harvard Health Publishing: “The Buzz About Caffeine and Health”
- U.S. Food & Drug Administration: “FDA Warns Consumers About Pure and Highly Concentrated Caffeine”