Caffeinated products, such as coffee, soda, tea, caffeine pills or other caffeine-rich sources, offer a quick pick-me-up to make you feel energized. While including these products in your diet once in awhile most likely won't cause long-term effects, too much can spike your blood pressure to unsafe levels. Check with your physician to ensure you are healthy enough to consume caffeine; it may interact negatively with certain medications or health conditions.
Blood Pressure
Blood pressure is the measure of the force of blood pushing against artery walls while your heart pumps. Systolic blood pressure, the top number, is the measure of pressure while your heart is pumping, Diastolic pressure, the bottom number, measures blood pressure while your heart is resting between beats. If your blood pressure gets too high it can damage artery walls, increasing your risk of heart disease.
Normal Blood Pressure
Ideally, your blood pressure should fall below 120/80 mmHg, where 120 is the systolic measure and 80 is the diastolic measure. When systolic rises to 120 to 139 mmHg and diastolic spikes to 80 to 89 mmHg, you may be at risk for prehypertension, or early high blood pressure. Ingesting caffeine may cause your blood pressure to rise to these levels, but it should drop back down as long as you are generally healthy. Hypertension, or chronic elevated blood pressure, is divided into two categories: stage 1 and stage 2. Stage 1 hypertension includes systolic blood pressure between 140 to 159 mmHg and diastolic between 90 and 99 mmHg. Stage 2 hypertension causes extremely high blood pressure where systolic soars above 160 mmHg and diastolic goes higher than 100 mmHg. If you have been diagnosed with high blood pressure, limit or eliminate caffeinated products to avoid spiking your blood pressure any higher.
Caffeine and Hypertension
Having two or three cups of coffee in the morning can raise your systolic blood pressure by as much as 3 to 14 mmHg and your diastolic by 4 to 13 mmHg, says Dr. Sheldon G. Sheps of the Mayo Clinic. This sudden spike in blood pressure may be caused by caffeine's ability to help your body release adrenaline, which naturally raises blood pressure, giving you that sudden burst of energy. Caffeine may also block a certain hormone that keeps arteries wide, causing your heart to pump harder to get blood flowing, increasing pressure.
Caffeine Content
Having an 8-oz. mug of coffee in the morning provides approximately 95 to 200mg of caffeine. According to research published in the "European Journal of Clinical Nutrition" in 2010, consuming a cup of coffee containing 130mg of caffeine keeps your blood pressure elevated for an hour or more. Over time, this can damage cells in the endothelium, which is the lining of vessels and arteries. Researchers concluded that caffeinated coffee has negative effects on blood pressure, which could eventually increase your risk of heart disease. If you need your caffeine in the morning but are concerned about blood pressure, switch to tea instead. An 8-oz. cup of black tea has anywhere from 40 to 120mg of caffeine, or about half as much as coffee.
References
- MayoClinic.com; Caffeine: How does it affect blood pressure?; Dr. Sheldon G. Sheps; November 2009
- National Heart, Lung and Blood Institute; What Is High Blood Pressure?; April 2011
- "European Journal of Clinical Nutrition"; Acute Effects of Coffee on Endothilial Function in Healthy Subjects; S. Buscemi, et al; February 2010
- MayoClinic.com; Caffeine content for coffee, tea, soda and more; October 2009
