Mmm… coffee, the aroma, the flavor. It makes mornings so much better! But is our daily cup of coffee doing more harm than good? There is a lot of research concerning both the negative and the positive effects of coffee drinking.
The “Pros”
- Antioxidants. Coffee is loaded with antioxidants like chlorogenic acid and melanoidins. Antioxidants help prevent oxidation, a process that causes damage to cells and contributes to aging. Melanoidins from roasted coffee have antioxidative effects depending on the way the coffee is treated.
- Parkinson’s disease. Regular coffee consumption reduces the risk of Parkinson’s disease. A number of studies [1],[2] have demonstrated that people who drink coffee on a regular basis are significantly less likely to develop Parkinson’s disease.
- Diabetes. Coffee consumption is potentially protective against the development of type 2 diabetes. A prospective cohort study as part of the US Nurses Health Study found that moderate consumption of both caffeinated and decaffeinated coffee may lower the risk of type 2 diabetes in younger and middle aged women.
- Liver cirrhosis. Coffee drinking may protect against liver cirrhosis, especially alcoholic cirrhosis.
- Gallstones. There is some evidence that coffee drinking may be protective against gallstone formation in both men and women.
- Kidney stones. Coffee consumption lowers the risk of kidney stones formation. Coffee increases the urine volume, preventing the crystallization of calcium oxalate, the most common component of kidney stones.
- Improved mental performance. Caffeine in coffee is a well-known stimulant. Coffee promotes alertness, attention and wakefulness. The cup of coffee can also increase information processing.
- Alzheimer’s disease. Regular coffee consumption seems to protect against Alzheimer’s disease. Recent mouse study showed that caffeine equivalent to 5 cups of coffee per day reduced the build up of destructive plaques in the brain.
- Asthma. Caffeine in coffee is related to theophylline, an old asthma medication. Caffeine can open airways and improve asthma symptoms.
- Caffeine safety. In 1958, caffeine was placed on the Food and Drug Administration’s list as generally recognized as safe (GRAS).
The “Cons”
- Heart disease. The relation between coffee consumption and risk of cardiovascular disease has been examined in many studies, but the results remain controversial. Most prospective cohort studies have not found coffee consumption to be associated with significantly increased cardiovascular disease risk.
On one hand, diterpenes cafestol and kahweol present in unfiltered coffee and caffeine each appear to increase risk of coronary heart disease. High quality studies have confirmed the cholesterol-raising effect of diterpenes. Coffee consumption is also associated with an increase of plasma homocysteine, a risk factor for coronary heart disease.
On the other hand, a lower risk of heart disease among moderate coffee drinkers might be due to antioxidants found in coffee.Besides that, caffeine can increase the risk of heart attack, especially among those people who carry the “slow” gene variant for the enzyme that metabolizes caffeine.
- Cholesterol. Heavy consumption of boiled coffee elevates blood total and LDL cholesterol (“bad cholesterol”) levels. Unfiltered coffee contains two cholesterol-raising compounds cafestol and kahweol.
- Blood vessels. Coffee negatively affects the blood vessel tone and function (increases arterial stiffness and wave reflections).
- Heart rhythm disturbances. Coffee can cause rapid or irregular heartbeats (cardiac arrhythmias).
- Blood pressure. Although coffee consumption is not a significant risk factor for hypertension, it produces unfavorable effects on blood pressure and people prone to hypertension may be more susceptible. Recent Italian study found that coffee drinking can slightly increase the risk for development of sustained hypertension in persons with elevated blood pressure.
- Osteoporosis. Coffee intake may induce an extra urinary excretion of calcium. Heavy coffee consumption (4 cups=600 ml or more) can modestly increase the risk of osteoporosis, especially in women with a low calcium intake.
- Heartburn. A cup of coffee can trigger heartburn.
- Sleep. Most of us are aware of the stimulatory effects of caffeine. High amounts of caffeine taken before going to sleep, can cause restlessness and difficulty falling asleep, tendency to be awakened more readily by sudden noises, and a decreased quality of sleep. However, some people can drink coffee and fall right asleep.
- Dehydration. The caffeine in coffee is a mild diuretic and can increase urine excretion. This effect may be easily neutralized by drinking an extra glass of water.
- Dependence. Caffeine is a drug, a mild central nervous system stimulant, and it produces dependence. Caffeine withdrawal is a real syndrome. You may get a few days of headache and irritability if you choose to quit drinking coffee, however, it is relatively easy to break this habit, and most people are not addicted to caffeine.
So, what is the key? The old principle – “everything in moderation” – holds true for coffee. It is not bad unless you abuse it. Coffee has its downsides, but offers enough good points to make it a worthwhile drink. For moderate coffee drinkers (3-4 cups/day providing 300-400 mg/day of caffeine), there is little evidence of health risks and some evidence of health benefits. And for sure you can enjoy your coffee as part of a healthy diet.
Written for Dumb Little Man by Christine Simmons, contributing author for HealthAssist.net