People who take Accutane (Isotretinoin) need to stick to regular anti-acne diet advice and try to avoid cow's milk, dairy, sugar, and refined white flour. It is recommend to eat a lot of proteins and vegetables to help your skin heal faster. Since Accutane is related to Vitamin A, you need to avoid vitamin supplements that contain Vitamin A.
Here is more info on acne or cystic acne and diet, that will provide a good guideline to get started on cleaning up your diet and acne.
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