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Healthy Eating

Coffee: a healthy perk or a risky indulgence?

By Anne E. Stein
Contributing writer

More than half the U.S. population drinks coffee every day, and another 25 percent drinks it occasionally. Some of us can’t leave the house without our daily cup of joe.

But is coffee good for you? If you gulp down a daily dose of caffeine, are you hurting or helping your health? Scientists have been studying coffee for years, and there are currently about 20,000 studies on coffee’s effects.

Shirley Vouris, clinical dietitian at Galter LifeCenter, says that if you drink coffee without suffering any side effects, one to two cups a day is just fine. If you’re not a coffee drinker, she advises, “don’t start drinking coffee for the health benefits.”

Below, we take a quick look at myths and facts when it comes to coffee and your health.

Does coffee cause bad breath?
Researchers at Tel Aviv University found that certain components in coffee actually inhibit bacteria that lead to bad breath. That said, coffee does have a strong aroma that can stay on your breath for a while, particularly if you add sweeteners.

"We think that coffee, which has a dehydrating effect on the mouth, can ferment into bad breath when mixed with substances such as milk,” according to Dr. Mel Rosenberg.

Does coffee raise cholesterol?
Studies show that drinking at least six cups a day of unfiltered coffee raises total and LDL (bad) cholesterol. It’s thought that the increase is caused by oils found in coffee called terpenes, which are mostly removed by coffee filters.

Does coffee protect you from Type 2 (adult-onset) diabetes?
A Harvard Medical School study (among many on this topic) found that drinking two cups of coffee a day can lower the risk of Type 2 diabetes by 42 percent. Drinking one cup a day lowered the risk by 13 percent. Other caffeinated beverages and decaf coffee didn’t offer the same level of protection. 
Does coffee reduce the risk of colon cancer?
An antioxidant called methylpyridinium — found almost exclusively in coffee — boosts blood enzymes that are believed to protect against colon cancer. Methylpyridinium is formed in the roasting process. The stronger the coffee, the higher the level of the compound, with darker roasts having two to three times more than medium roasted beans.

Does coffee protect against other cancers?
Researchers analyzed nine studies collected by the International Head and Neck Cancer Epidemiology consortium and found that people who drank four or more cups of coffee a day were 39 percent less likely to develop oral and pharynx cancers than people who didn't drink coffee.

Does coffee cause weight gain?
If you load it with cream and sugar, don’t eat a healthy diet, and don’t exercise, then yes, the things you add to coffee (not the coffee itself) can cause weight gain. 
Does coffee cause headaches?
That depends on the person. The caffeine in coffee can cause headaches if you drink more than four to five cups a day. Quitting coffee cold turkey can also cause headaches. If possible, decrease your coffee consumption gradually and be aware of other caffeine sources in your diet.  
Does coffee help or hurt athletic performance?
The International Olympic Committee, along with plenty of scientists, thinks that caffeine is a performance-enhancing drug. Studies have found that coffee helps release free fatty acids which can improve athletic performance, while caffeine reduces the pain experienced in moderate to intense exercise. 

Does coffee cause dehydration?
Yes and no. Caffeine’s a mild diuretic, but after three to five days of drinking caffeinated beverages, the body adjusts to eliminate the dehydrating effects.  
Does coffee contain antioxidants?
According to a study published in the Journal of Agricultural and Food Chemistry, coffee, depending on the bean and brewing method, can have four times the antioxidant content of green tea.  

Do regular coffee drinkers become immune to coffee’s effects?
Some people develop a tolerance to its stimulatory effects. In these cases, caffeine brings heavy coffee drinkers back up to baseline or "normal” — rather than giving them a boost — because they are living in withdrawal without coffee.

Will coffee help me get pregnant?
According to scientists at the American Society for Reproductive Medicine, caffeine in coffee appears to increase sperm “motility” (the speed at which sperm moves), and heightened motility increases the odds of pregnancy.

Is coffee bad for my heart?
One study found that drinking two or more cups of coffee a day can increase the risk of heart disease in people with a mutation that slows caffeine breakdown in the body. Occasional coffee drinkers might have a spike in blood pressure. With regular coffee drinkers, according to the Mayo Clinic, tolerance develops and the blood pressure falls to previous levels.

Does coffee cause nervousness and irritability?
If you’re already stressed out, don’t overdo coffee. Drinking more than four cups a day can cause anxiety, sleeplessness and irritability, especially in people who are prone to those.