When you eat or drink caffeine, it influences your central nervous, cardiovascular, metabolic and urinary systems. The central nervous system innervates the cardiovascular system, causing a rise in both blood pressure and heart rate. The metabolic system becomes influenced by the release of fatty acids into the bloodstream. Caffeine is a diuretic and increases urine output by the kidneys. Each of these factors can have an affect on a person with heart disease.
Cardiovascular Effects
Caffeine intake, whether it be from a cup of coffee, soda or food, can affect your cardiovascular system. Caffeine is a stimulant that increases blood pressure and heart rate. According to a study published in 1999 in the "European Journal of Clinical Nutrition," for most, the effects of caffeine on blood pressure are safe, but for a patient with heart disease, this effect may be harmful. If you have been diagnosed with hypertension, caffeine intake should be avoided or limited.
Metabolic Effects
Caffeine ingestion prompts the release of free fatty acids inside of the blood. While useful for an athlete during a competition, for a person with heart disease, it can be dangerous. Patients with heart disease are not able to clear and use fatty acids in the blood like an athlete can. Therefore, these fatty acids can stay in the blood until the body clears them. This can be harmful for a patient with heart disease by contributing to high cholesterol.
Caffeine as a Diuretic
Diuretics increase your urine output. This can be harmful for a person with heart disease for two reasons: dehydration and kidney stress. Producing excess amounts of urine can cause dehydration. Dehydration increases your heart rate and can profoundly decrease your blood pressure. Dehydration may also lead to certain heart arrhythmias. Secondly, it is stressful to the kidneys, which may be already feeling the effects of your heart disease.
Considerations
If you are a heart patient who has a hard time giving up your morning cup of coffee, there are alternatives. Decaffeinated coffee or tea are a means to get your wake-me-up without the harmful effects of caffeine. Limiting foods that contain caffeine, like chocolate, will benefit you by decreasing your caffeine intake and your waistline. Moderate caffeine intake may be safe for most people. If you are unsure of what to do, consult your doctor. He can advise you on your caffeine intake based on your personal medical history.
References
- American Heart Association: Caffeine
- "European Journal of Clinical Nutrition"; Coffee, Caffeine and Blood Pressure: A Critical Review; M.L. Nurminen, et al.; 1999
- "Exercise Testing and Prescription"; David C. Nieman; 2007
- MayoClinic.com: Dehydration: Complications
