The National Coffee Association reports that as of 2010, 56 percent of adults older than the age of 18 drinks coffee on a daily basis. Coffee naturally contains caffeine -- a central nervous system stimulant that gives coffee the ability to kick-start your morning or afternoon. Consuming coffee causes physical changes in your body making it a topic of research for a variety of health issues, including its effect on the adrenal glands.
Coffee Effects
Consuming caffeine stimulates the central nervous system and causes the neurons in the brain to fire more rapidly. The pituitary, a gland located at the base of the brain, detects the increased brain activity, recognizes it as stress and signals the adrenal glands to produce and secrete the stress hormones. The release of the stress hormones causes the physical symptoms you experience after drinking coffee, including an increased heart rate that can cause you to feel jittery or anxious and dilated pupils. The stress hormones also affect your blood vessels and blood pressure.
Adrenal Function
Your adrenal glands play a major role in the "fight or flight" response. When you encounter a stressful situation, whether real or perceived, the adrenal glands produce three important stress hormones. Cortisol, produced in the outer portion of the adrenal gland known as the adrenal cortex, aids in the breakdown of fats and carbohydrates and increases blood sugar levels to provide added energy to the muscles making them ready to fight or flee. The inner portion of the adrenal glands, known as the adrenal medulla, produces epinephrine and norepinephrine, also known as adrenaline and noradrenaline. Epinephrine increases the rate and force of your heart beats, which increases the flow of blood to your muscles and brain. Norepinephrine causes blood vessels to constrict, which causes your blood pressure to increase.
Study
A study published in a 2002 issue of "Psychosomatic Medicine" reports that caffeine, like that found in coffee, causes a 32 percent increase in epinephrine levels in the blood. The study concludes that when patients experience daily stress, the caffeine exaggerates the adrenal response to the stress resulting in higher increases in blood pressure.
To Drink or Not To Drink
Despite evidence that coffee increases health risks associated with high blood pressure and heart disease, doctors at the Harvard Medical School confirm that drinking coffee in moderation -- one to two cups per day -- is safe for most people. Maintaining healthy adrenal glands helps to maintain a healthy blood pressure and heart. Drinking excessive amounts of caffeinated coffee causes your adrenal glands to increase hormone production when your body does not need the hormones. Over time, this can aggravate your adrenal glands and affect your overall hormone balance.
References
- National Coffee Association: 2010 National Coffee Drinking Trends Survey
- Women to Women; Caffeine and Your Adrenals; Marcelle Pick, April 2011
- "Psychosomatic Medicine -- A Journal of Biobehavioral Medicine"; Caffeine Affects Cardiovascular and Neuroendocrine Activation at Work and Home; Lane J.D. et al.; Jul-Aug 2002
- University of Rochester; Caffeine; April 2008
- University of Maryland Medical Center; Anatomy of the Adrenal Glands; August 2010
- Harvard School of Medicine; Coffee Health Risks; August 2004
