Under normal circumstances, the upper layer of our skin (the epidermis) which also lines our skin pores that connect the oil glands (sebaceous gland) to the surface, is continuously being reproduced, with the dead skin cells on the surface and lining of our skin pores shed from the surface without our knowledge.
Increased oiliness of the skin which usually occurs when hormonal androgen levels rise at puberty unfortunately makes these skin cells stick together forming a small plug, which then blocks the skin pore.
Bacteria living on the skin in oily areas such as the face and body soon become trapped deep within the skin pore and oil (sebaceous) gland where they begin to multiply happily in this warm oily protected environment. The oil gland soon becomes red and swollen (papules and pustules) and with time large inflamed nodules and cysts develop. When these cysts or nodules eventually rupture the pus and inflammation within penetrates deep into the dermis of the skin where collage, elastic and other supportive tissue are damaged leading to irreversible scarring.
Adult acne affects up to 15% of women
The acne is present after the age of 25 years and is either a continuation of adolescent acne or has commenced for the first time in adult life
Whilst adult acne usually presents as typical teenage acne it often has the following specific characteristics:
- The acne is very persistent and may continue into the 30s and 40s.
- It tends to be mild to moderate in severity.
- Affected women often complain of large pores.
- Inflammatory lesions are common on the lower face (“bottom heavy acne”) especially around the jawline and neck but may be seen anywhere on face, neck, chest or back.
- Acne breakouts just before menstruation are a common complaint
- Large whiteheads (macrocomedones) are more common than in teenage acne, and are mostly found on chin, cheeks and forehead.
- External factors have been shown to contribute to comedonal break outs in some adult women, particularly poor skin care products and smoking
- Dietary factors, particularly a high GI diet are thought to be one reason for an increasing prevalence of adult acne
- Onset of inflammatory lesions (papules and pustules) may be associated with stress
Adult acne may be associated hormonal factors such as pregnancy, polycystic ovary syndrome, and medications and supplements that promote androgenic (male hormone) activity and sebaceous gland stimulation.
Interestingly Acne is a disease of Western civilisation and is absent in populations consuming Paleolithic diets without refined sugars, grains, milk and dairy products.
The Glycaemic Index (GI) is a way of ranking carbohydrates according to their effect on blood sugar levels. The lower a food’s GI value, the slower and less severe it causes blood sugar to rise when you eat carbohydrate-based foods.
A diet with a low glycaemic load has been shown to reduce the size of the sebaceous glands (reduces sebum production), decrease inflammation in acne, reduce acne lesion count (less comedones, papules and pustules) and diminish production of inflammatory chemicals produced in the skin of acne sufferers
On the other hand research has shown that when a diet with a high glycaemic load is consumed the levels in the blood of insulin and another hormone called Insulin Growth Factor 1 (IGF-1) become elevated. Insulin and IGF-1 both increase androgen hormone levels, which increase sebum (oil) production, as well as increasing production of skin cells around the skin pore making blockages more likely.