According to a new report from Harvard Medical School, replacing saturated fats with polyunsaturated (found in fish and some vegetable oils) can cut the risk of heart disease by one-fifth. Analyzing the findings of eight previous studies covering over 13,000 people, they found that cutting saturated fats from butter and meat was important for heart health, adding that adults should get no more than 11 per cent of energy from saturated fats because they raise the levels of bad cholesterol, blocking arteries to the heart. Meanwhile, polyunsaturated fats increase the levels of good cholesterol. For every five per cent increase in polyunsaturated fat consumption, the team reported, there was a 10 per cent drop in heart disease. Trans-fats, found in processed foods like biscuits and cakes, are not a good replacement.