Trans fats are made through a process known as partial hydrogenation—basically, when you add hydrogen to ordinary vegetable oil, it becomes solid at room temperature, making it a cheap substitute for butter. According to Teicholz "A daily intake of five grams of trans fats increases the risk of contracting heart disease 4 percent to 28 percent." Apparently, the pushing of trans fats out of the American diet is already paying dividends.