I don't get involved in this area but I would like to point you in a slightly different direction.
From a book called Practical Dietetics with Special Reference to Diet in Disease by Gilman Thompson
It has long been known that a relation exists between diet and certain skin diseases. Attention has been directed to the importance of systematic dietetic treatment to aid the cure of such ailments, and a more thorough investigation of this subject is much to be desired.
Skin Diseases Which Are Caused By Improper Diet include erythema, urticaria, acne, eczema, and scorbutic eruptions.
Many chronic skin diseases, if not originally caused by diet, are undoubtedly much protracted and made worse by them. This is particularly true of eczema, impetiginous and seborrhceic ecthyma, strophulus, and the cutaneous lesions of the tuberculous diathesis, and sometimes of psoriasis.
The modes of production of cutaneous eruptions by diet are complex. Probably in the majority of instances such eruptions are due to malfermentation products, ptomaines, etc., which are absorbed through the digestive tract. In other cases they may be due to an effort to eliminate incompletely oxidised food products or poisons from the cutaneous glands (as in the case of drug rashes), and it has been suggested that they may be sometimes caused by reflex nerve irritation from the alimentary canal, although the latter theory is less tenable. It is, however, interesting to observe the fact that an intimate relation often exists between irritation and inflammation of the skin and of mucous membranes. Overeating, and especially the overfeeding of infants, is a common cause of skin eruptions, and the attempted elimination by the sweat glands of fatty acids is irritant.
General Principles Of Dietetic Treatment
There are certain general principles of dietetic treatment which are applicable to a majority of all severe cases. The food should be of simple kind, restricted in variety, and plainly cooked. Milk,-meat, and stale bread are more desirable than amylaceous or saccharine food. In the case of scorbutic eruptions the trouble arises sometimes (but not always) from malnutrition from withholding certain articles, such as fresh fruit and vegetables, from the diet.
Substances to be particularly avoided in skin diseases are raw and unripe fruits and vegetables, sweets and pastry of all kinds, condiments and highly seasoned dishes, veal, pork, and alcoholic beverages.