Many professional golfers use smokeless tobacco, but few want to admit it, according to The New York Times. Players say using chewing tobacco or snuff is a form of male bonding.

According to the National Cancer Institute, smokeless tobacco causes oral cancer, esophageal cancer and pancreatic cancer. It may also cause heart disease, gum disease, and oral lesions other than cancer. All tobacco products, including smokeless tobacco, contain nicotine, which is addictive.

Stanton Glantz, Director of its Center for Tobacco Control Research and Education at the University of California at San Francisco, said the brain and nervous system of a person using smokeless tobacco are like a stereo system with the volume turned up too high. He explained the nicotine acts like pillows over the speakers. If a person stops using smokeless tobacco, it is like taking the pillows away—the volume becomes too loud. “It causes anxiety, and that helps explain why these guys are compulsive users,” he said.

Because golfers on the PGA tour are supposed to be role models, they try to be discreet about using smokeless tobacco, the newspaper notes. Golfer Brian Gay said, “If I know I’m on the television camera, I’ll be more conscious of doing it. And if I’m going along nicely, I might not use it.”

Bruce W. Adkins, Director of the Division of Tobacco Prevention of the West Virginia Bureau for Public Health, said it is difficult for golfers who use smokeless tobacco to control their nicotine intake. “One of the things that we know from lots of research is smokeless tobacco products are high in nicotine,” he said. “If you keep on average a pinch in your mouth for 30 minutes, you’re getting an equivalent amount of nicotine to smoking four or five cigarettes. That’s part of the addiction.”