Health experts on coffee: Don’t say no to that cup of joe

Officials respond to California court ruling on cancer warning

Los Angeles — A California court ruling this week that a cancer warning label should be required on coffee has left the scientific community puzzled.

There is plenty of research showing that coffee doesn’t cause cancer, and can actually prevent liver and endometrial cancer. The World Health Organization announced two years ago that there was “no conclusive evidence for a carcinogenic effect of drinking coffee.”

The decision has put public health experts at odds with a state law aimed at safeguarding the health of Californians.

“I can understand the logic of the judge, by going by the book. But I can also understand the science,” said Mariana Carla Stern, a University of Southern California professor who studies diet and cancer. “From the science standpoint, there’s no reason the public should worry about drinking coffee.”

California’s Proposition 65, officially known as the Safe Drinking Water and Toxic Enforcement Act of 1986, requires that businesses warn customers if they could be exposed to any of the more than 900 confirmed or suspected carcinogens. One of the compounds on the list is acrylamide, which is found in french fries, burnt toast and roasted coffee beans.

Some studies in animals have found that exposure to high levels of acrylamide causes cancer, but there’s little evidence of that in humans, said Kathryn Wilson, a Harvard senior research scientist who studies links between diet and cancer. Researchers also warn that it’s unwise to extrapolate acrylamide studies in animals to humans because the species metabolize the compound differently.

“I think it’s crazy,” Wilson said of the court’s decision. “Reducing coffee or french fries to their acrylamide content isn’t how we study diet and nutrition.”