It may help to reduce your intake of meat, animal fats, sugar and alchahol and increase intake of fibre, fruit, vegetables, cooked dried beans and peas, nuts and seeds.
Eat more oily fish, particularly mackeral, sardines, herring and salmon.
An oatmeal bath can can help to soothe irritated skin. Put 1kg of oatmeal in cheesecloth bags in a hot bath and soak for about 15 minutes. Apply your treatments afterwards.
Excercise can help reduce stress which can be a contributing factor.