I would say that butter is not one of the foods that would normally cause acne, but for certain people, adding more butter and oil can cause Acne by making the skin more oily, this can increase the chance of breakouts. If your liver is in perfect condition, then you can eat a lot of butter with no problem, but if your liver is unhealthy and you are not producing enough bile, your body will not be able to properly break down and digest butter and other fats and this could cause acne. Usually, there are a variety of factors together that cause acne, but experimenting with different diets and eliminating various foods can have a good impact on eliminating or at least reducing acne. There are no specific foods that are known to contribute to acne. Many different doctors and nutritionists have compiled lists of certain foods that may trigger acne, but really it is specific to each person.