The onset of ageing can be retarded by a judicious use of oils, a healthy lifestyle and drinking lots of water

Talking about the “integument” sounds more scientific, but it is just another word for our skin. The existence of the skin is often forgotten or taken for granted, even though it protects our body and makes up for an incredible 15 per cent of its weight. It is composed of an outer layer called the epidermis containing the blood vessels, sweat glands and nerve endings, three intervening layers and, finally, the dermis which anchors it to the deeper body structures.

The skin holds the body together and protects it from the outside environment, physical injury, friction, chemicals and infection. It maintains the body temperature by regulating the rate of sweating. It is plentifully supplied with nerves so that it is sensitive to touch and pain. It synthesises vitamin D with the help of sunlight and this keeps our bones strong and prevents osteoporosis.

Regeneration and shedding of the skin occurs at a controlled rate. As old skin falls off, new skin forms from underneath to replace it. This process is auto regulated. If the signals are faulty (usually due to genetic causes), the skin builds up faster than it is cast off or the shedding occurs at an unusually rapid rate. This is the basis for many non-infectious skin diseases with unsightly plaques, flakes and patches like psoriasis, icthyosis and dandruff.

The cells in the skin are also prone to releasing histamine (a chemical causing itching) at the slightest provocation. This can occur from self-inflicted injuries like scratching, pressure from tight clothes or as a result of exposure to chemicals and substances in the environment. Consumed allergens can also be carried to the skin through its ample blood supply, producing rash and intense itching. This is a self-perpetuating cycle, so that “the more you scratch the more you itch”.

Itching may be due to infestation with skin parasites like scabies or lice. Infection because of fungi like Candida causes itching, especially in moist, covered areas like the armpit and groin. It may be aggravated by detergents used to wash the clothes, particularly if they have not been properly rinsed. Chemicals like Dettol or liquid blue may be added after rinsing, which may precipitate itching.

Generalised uncontrolled itching can occur if the skin becomes very dry. There is no rash visible, but the desire to scratch is uncontrollable. This occurs naturally with ageing and sometimes during pregnancy.

Medication can aggravate itching. If multiple drugs are consumed, leading to a poly-pharmacy situation — as sometimes occurs in the elderly — the exact medication causing the problem may be difficult to pinpoint.

Some diseases (unrelated to the skin) cause itching and can develop into rashes as the first symptom. Common culprits are diabetes, thyroid malfunction, kidney or liver failure and iron deficiency. Uncontrolled itching can be due to internal cancers, particularly the blood cancers and lymphomas. In some of these, like Hodgkin’s disease, the itching is aggravated with drinking.

Matrimonial advertisements in newspapers invariably speak of “fair skin” and “wheatish complexion”, showing our obsession with skin colour. They do not describe a potential bride as having sun burnt, or yellow-orange or slate grey skin. Yet all these conditions are possible. Sunlight exposure tans the skin, superficial tumours may be red, jaundice makes the skin yellow and eating too many carrots or papayas makes it orange (carotinaemia). The skin can also turn violet with subcutaneous bleeding or Kaposi’s sarcoma (now prevalent as one of the complications of HIV infection). Purple discolouration under the eyes can occur with auto immune diseases like dermatomyositis. Some natural “health” preparations contain heavy metals like silver and gold. If they are specially prepared for a rich client, more of the precious metals may be added. However, these metals accumulate in the skin, eventually turning it slate grey.

Intrinsic ageing, or the natural ageing process, affects the skin from the 20s. A number of extrinsic factors like excessive exposure to sunlight, repetitive facial expressions, gravity, sleeping positions (prone to sleep on the same side), an unhealthy diet (excessive oils and too little vitamins) and smoking often accelerate the natural ageing process. Ageing produces fine wrinkles, thin and transparent skin, loss of skin fat with increased susceptibility to cold, shrinking and sagging, loss of natural oils with dry, itchy skin and reduction in the number of sweat glands, causing intolerance to heat. The onset of ageing is genetic, but premature ageing can be retarded by a judicious use of oils, a healthy lifestyle and drinking plenty of water.

Our skin presents our face to the world. To take good care of it —

Treat any medical diseases aggravating skin changes

Moisturise the skin regularly with oils and creams to keeps it elastic and soft

Drink at least 2-3 litres of water a day.

Dr Gita Mathai is a paediatrician with a family practice at Vellore. Questions on health issues may be emailed to her at yourhealthgm@yahoo.co.in