Heart palpitations can be scary. You feel like your heart is racing or pounding and perhaps it's irregular. You may suddenly notice you can feel your heartbeat in your chest, throat or neck. A variety of things can affect your heart and cause palpitations --- one of them is coffee.
Palpitations
According to MedlinePlus, the normal heartbeat is between 60 and 100 beats per minute. What many people call palpitations is a heart rate above 100 beats per minute, or tachycardia. Palpitations can also include extra beats, known as extrasystole. Palpitations are not usually serious, but if there is underlying heart disease or the heartbeat is truly abnormal, they can signal a problem. For example, a low potassium level in your blood can cause an irregular heartbeat. Stress, some medications, tobacco products, thyroid disease and caffeine can all contribute to palpitations.
Research
Caffeine is the one substance in coffee most likely to cause palpitations. In one study in Australia, M.J. Shirlow and C.D. Mathers found that the higher the caffeine intake, the more likely study participants were to report symptoms such as indigestion, tremor and palpitations. Consumption of approximately 4 to 5 cups of coffee increased the risk of palpitations by a factor of 1.6. The study results were reported in the 1985 "International Journal of Epidemiology."
Research on Women
In a more recent study reported in the September 2008 issue of "Nutrition Research," study leader Michael Kennedy noted the team wanted to look at the effects on women of a normal cup of coffee, which the team defined as 12 oz. of coffee containing about 140 mg of caffeine. After drinking the coffee, study participants were given a mentally stressful test. Heart rate increased an average of six beats per minute both in women who habitually drank coffee and in those who never drank it.
Considerations and Warnings
If you feel your coffee consumption may be causing palpitations, discuss your concerns with a health care professional. If you have palpitations and also develop shortness of breath, chest pain, unusual sweating, dizziness or lightheadedness, seek emergency help immediately.
References
- "International Journal of Epidemiology"; A Study of Caffeine Consumption and Symptoms: Indigestion, Palpitations, Tremor, Headache and Insomnia; M.J. Shirlow, et al.; 1985
- MedlinePlus Medical Encyclopedia: Heart Palpitations
- "Nutrition Research"; The Cumulative Effect of Coffee and a Mental Stress Task on Heart Rate, Blood Pressure, and Mental Alertness Is Similar in Caffeine-Naive and Caffeine-Habituated Females; Michael D. Kennedy, et al.; September 2008
