More evidence that there are good fats and there are bad fats.  And the good ones don’t say “moo” or “oink” or even “cock a doodle doo” before arriving on your dinner table.

Men with prostate cancer, who switch to a diet high in vegetable fats, such as those in nuts and olive oil, may be less likely to have their disease spread.  That’s according to a new study published in the Journal of the America medical Association.

But the opposite was true for men eating lots of saturated and trans fats often found in meat and processed foods.

Duke University Medical Center urologist Dr. Stephen Freedland says it changes the conventional wisdom on diet and nutrition:  “It actually says, if you eat more fat, albeit the right kind of fat, you're less likely to die of not only prostate cancer, but really of any cause, which really flies in the face of this ‘low-fat, low-fat, low-fat' mantra that we've been told for decades now.”

Erin Richman of the University of California, San Francisco found that switching 10 percent of daily calories from carbohydrates to vegetable fat was linked to a 29 percent lower risk of lethal prostate cancer and a 26 percent lower chance of dying from any cause.

“The benefit was really when you were replacing refined carbohydrates with (things like) olive oil and nuts,” Richman said.