Oils and fats are the most concentrated energy food in our diet.
The 1994 review of nutritional aspects of heart disease suggests a
maximum proportion of energy from fat of 35% of the dietary energy intake, and a maximum of 10% from saturated fat. The best level is much lower than this, but a very low fat diet is equally unhealthy.
Butter is made by separating the milk fat from the liquid. It is 80% fat and contains no protein. It should not be excluded from the diet as it is an excellent natural source of vitamin E.