In our analysis of prospective studies totaling 140,000 men and women, we determined that intake of 2% of total calories from trans fats (or 40 calories/day, for a typical 2000 calorie/day diet) was associated with 23% higher risk of heart attacks or death from heart disease. This indicates that for every 100,000 individuals suffering a heart attack or death from heart disease each year, 19,000 of these would be prevented if the average trans fat intake were reduced by approximately 40 calories/day.