This from USNews via Left Off Colfax:
But “if you’re already drinking five or six cups a day, I’d be hard pressed to come up with a reason you should cut back,” says Walter Willett, chairman of the department of nutrition at Harvard School of Public Health and a leading investigator of coffee.
…A word of caution: Decaf coffee may be an exception to this rule. A recent Stanford study found that even consumers of filtered decaf had modestly higher levels of fatty acids and other precursors of LDL, or bad cholesterol.