The causes are not known but probably include a combination of inherited bad genes, bad diet (too much fat and redmeat, too few vegetables) and random genetic errors that occur as cells divide.
It is important to take in adequate amounts of lean protein such as chicken, fish, lean redmeat, egg whites, low-fat cottage cheese or a protein supplement.
But they may help explain the underlying risk of eating redmeat, which some researchers have long thought was higher than the saturated fat and cholesterol content alone could explain.