Butter and traditional margarine contain the same number of kilojoules. However, many vegetable oil-based spreads now contain less far than previously. Butter naturally contains vitamins A and D and, by law, these vitamins are added to margarines and spreads. But they differ in other ways. Butter contains more saturates (54 percent) and less polyunsaturates (5 percent) than soft margarines and spreads (which contain 16-26 percent saturates and more than 40 percent polyunsaturates). As most people need to limit their consumption of saturated fats while increasing their intake of polyunsaturates, margarine is the healthier choice.
However, cooking margarines can contain up to 35 percent saturated fat and only a small amount of polyunsaturates. The differing cholesterol contents of butter and margarine may also be important to people concerned about heart disease. Most spreads made form vegetable oils are almost cholesterol-free.
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