For a drink that's little more than 500 years old, coffee has managed a remarkable conquest of our daily lives. Coffee can be said to be one of the few truly global beverages, and yet it is so much more than a popular drink. Today, its consumption stands at a whopping 12 kg per person per day in the most java-hungry nation – Finland – where just a few centuries ago, the brew would have been a little-heard-of curiosity from Arabia. Brazil, which exports 5.7 billion pounds of coffee a year – 60% more than the runner-up, Vietnam – owes a significant chunk of its economy to this unassuming bean.

Should I Skip the Jitter Juice?

Is coffee bad for you? Caffeine, the chemical component that gives coffee its kick, is one of the most hotly contested subjects in science with studies claiming both that the substance is a killer and a lifesaver. Here ... let's look at the good and bad characteristics of caffeine.

1. The Good

• Mental Stimulant – Perhaps the only thing experts can agree on is that caffeine is a stimulant that increases mental alertness, boosts metabolism, and improves overall performance under sleep deprivation. However, these effects are generally short-term and can diminish upon regular consumption of caffeine.

• Reduced Risk of Parkinson's Disease – Studies have shown coffee drinkers have a reduced risk for Parkinson's disease with the decrease in risk tied to the level of consumption. Three to four cups of coffee a day for men and one to three cups a day for women appears to cause the greatest reduction in risk.

• Reduced Risk of Type 2 Diabetes – Coffee drinkers have been found to have up to 7% less risk of developing this disease which is characterized by high blood sugar levels. Some research claims even greater risk reduction.

• Fights Gallstones – 400 mg of caffeine per day reduces the risk of developing gallstones. Four or more cups of coffee daily seem to produce the greatest risk reduction. However, this effect is not seen in individuals consuming decaffeinated coffee which indicates caffeine and its ability to trigger contraction of the gallbladder may be behind this effect.

• Lowers Postprandial Hypotension – After meals, blood pressure tends to decrease, and this can cause dizziness in older people who stand up after eating. Coffee, as a vasoconstrictor (increases blood pressure), tends to decrease this effect. Patients who drink coffee prior to eating their meal generally see this great benefit of coffee consumption.

2. The Bad

• Nervousness – We've all drank one too many cups on a long night and felt the tremors, nervous energy, anxiety, and irritability associated with coffee jitters. Some people are more prone to these effects than others.

• Hypertension – Caffeine is a proven vasoconstrictor, so overconsumption might make your blood pressure a little high. In the long run, this could prove to be problematic, especially for people who already suffer from hypertension.

• Incontinence – Caffeine is linked to diuresis (increased urination) and has been shown to increase the risk of incontinence among women.

• Indigestion – Coffee consumption may not be good if you suffer from an uneasy stomach. Caffeine is known to cause indigestion and exacerbate diarrhea and irritable bowel syndrome as well.

• Decreased Bone Strength – Caffeine in high doses interferes with bone ossification. Menopausal women, women with trouble processing vitamin D, and anyone with osteoporosis should be careful with their coffee intake.

3. The Unknowns

Some of the benefits associated with coffee are supported by insufficient evidence.

• Lung Cancer Treatment – There is currently a deadlock on whether or not caffeine helps prevent lung cancer. Some researchers support this hypothesis while others do not. Note: Caffeine enema cancer treatments are not proven to be safe or effective.

• Reduced risk of gout – Gout is another disease which coffee may or may not help prevent.

How Much Coffee Should I Drink?

Almost as important as the question, "Is coffee bad for you?”, is the question, "How much coffee is bad for you?”. The evidence and health experts sometimes offer diverging opinions on this subject. Many research studies make it clear that four cups a day might hit the sweet spot between enhancing benefits and increasing risks. Most health experts seem to advise moderation more strongly, perhaps motivated by the see-sawing scientific opinion on caffeine. Coffee is good, but keep it to a cup or two a day, they say.

It seems safe to conclude that if you're drinking four cups a day, you probably aren't hurting yourself, but it may be a good idea to wean off the coffee a little bit. If you're drinking more than four cups a day, reducing consumption is imperative. Don't quit cold turkey! Instead, try to reduce your intake a cup at a time until you're down to a healthier two or three cups a day. If you're pregnant, it's probably best to limit intake to one cup a day.

Less Sugar and Cream

The coffee itself may not be very bad for you, but thanks to its popularity, a lot of people dress up the beverage and add a lot of calories by doing so. Avoid the creamy, chocolatey frappuccinos at expensive coffee shops. Cut back on sugar and cream in your own preparations, and stick to filtered coffee.

Final Thoughts

Perhaps because of its cultural significance, we rarely think objectively about the question, "Is coffee good or bad?” While there are plenty of studies venerating the health benefits of coffee, it is important to take them with a pinch of salt. "Everything in moderation” seems to be a good principle for sensible consumption. Enjoy your coffee – but not too much, and try not to go on a guilt trip about it. Stress is probably worse for your health than a mild addiction to caffeine.