The skin is the interface between the outside world and the inside world of our bodies and therefore is subject to influences from both. It is the first line of defence against invasion by micro-organisms from the outside world; partly because it represents a tough physical barrier and partly because our first line of defence against the outside world, i.e. the immune system, pain, sense of touch, heat and cold act in the skin first and warn us when we are running into trouble.
The skin reacts to adverse events with inflammation. Just seeing inflammation, therefore, does not tell us why there is inflammation, but it tells us there is some sort of noxious event either trying to get in through the skin, or get out through the skin. Thus, eczema may be an allergic reaction to foods, with the antigen coming out of the skin, or to chemicals coming out as part of a detox reaction, as in a drug reaction.
Skin is responsible for making vitamin D through the action of sunshine on the skin. We can use skin to detox using far infrared radiation or as a result of exercise. Skin is also vital for recognition of others.
Almost all skin problems will benefit from minerals and vitamins in creams. A coconut based cream will supply medium chain triglycerides which are the perfect fuel for friendly bacteria on the skin, adding ascorbic acid reduces free radical damage and magnesium stabilises mast cells to make them less irritable. This makes the skin more tolerant of allergens. Using minerals salts will hold water in the skin so hydrating it and again increasing the skin barrier to infections and allergens. Indeed there is good evidence that all these factors will slow the ageing of skin.