Abstract/Summary

Saturated fats have been implicated as one of the main dietary contributors to heart disease. These fats do not block our arteries directly, but can raise the concentration of blood cholesterol, which can form deposits inside arteries called 'plaques'. The plaques can then become unstable and rupture, causing blood clot formation and a heart attack or stroke. For this reason, dietary guidelines limit the amount of saturated fats we should eat. However, this recommendation has been challenged because of a seeming lack of evidence for a direct relationship between saturated fats and heart disease mortality, and the complexity of the relationship between saturated fats and blood cholesterol. When we eat less saturated fats, the effect on blood cholesterol and other risk factors often depends on what the fats are replaced with. This can be another type of fat (polyunsaturated or monounsaturated fat) or carbohydrate, all of which will lower blood cholesterol and heart disease risk, to variable extents, with greater benefits from unsaturated fats. Moreover, not all foods that contain saturated fats have the same effect on blood cholesterol, including dairy foods like butter and cheese. In comparison to butter, the saturated fats in cheese are absorbed in the gut to a lesser extent, which reduces the relative potential of cheese to raise blood cholesterol.