How Coffee Benefits the Liver
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For years, coffee got blamed for causing cancer, heart disease, osteoporosis, and more. Now doctors realize that those health troubles probably had more to do with coffee drinkers' cigarette and jelly doughnut habits than their morning cups of Joe. In fact, more studies are now showing that coffee carries several serious health benefits, such as staving off Parkinson's disease and type 2 diabetes. Researchers have just uncovered another big perk: Coffee can slash your risk of liver cancer by 40 percent.

A team of Italian scientists pooled 16 years' worth of data on more than 3,100 people to find a direct link between coffee consumption and fewer incidences of liver cancer, the third most common cause of cancer death. Some studies revealed that drinking at least three cups day may lower risk even further, to 50 percent.

Just how does coffee protect the liver? "There are a number of possible mechanisms," says Neal Freedman, an investigator with the National Cancer Institute. "Coffee is a rich source of antioxidants," which protect the body against disease-causing free radicals and inflammation. Freedman says coffee also may improve insulin signaling, which could help prevent diabetes, a known risk factor for liver cancer. "Many observational studies have suggested that people who drink coffee may be less likely to get diabetes," he says. "Having diabetes can increase your risk of developing liver cancer, so coffee drinking potentially protects against liver cancer by reducing your likelihood of diabetes."

But as with almost everything in life, too much of a good thing can be bad. A recent Mayo Clinic study found that people under age 55 who sipped more than four cups a day were twice as likely as non-coffee drinkers to die early.

"It's important to remember that coffee contains more than a thousand compounds and has a complex effect on the body," Freedman says. "Rather than changing your coffee drinking habit based on this or any particular study, discuss your coffee intake with your health-care provider, especially if you have any medical conditions."