Understanding Your Skin

Just wanna share this interesting info about our skin, so that we can take a really good care of it.. This article is basically tell us what are the causes that make our skin to be oily, dehydrated or sensitive. So, when you know why, then you can actually find the correct way to protect it. :-)

Our skin is our first line of defence against dehydration, infection, injuries and extremes of temperature. It combines strength with elasticity to help resist knocks and shocks. The skin can be up to 5m thick but this varies over the body. The thickest areas are the palms and soles and the thinnest are the eyelids - just 0.3mm thick.

Our skin is made up of layers - and upper layer of epidermis, and a lower layer of dermis. Below the dermis is the subcutaneous layer, containing fat and connective tissue, which shapes and cushions the body. 

The epidermis

The top layer of the epidermis are made up of dry, tightly knit cells filled with keratin, a fibrous protein (also found in hair and nails) that protects the skin and stops it drying out. These cells can absorb about 5 times their weight of water and swell to 3 times their original thickness.

The epidermis works ceaselessly to regenerate itself. The cells are born in the lowest layer of epidermis and migrate upwards for about 2 weeks, during which time they flatten out and die. Eventually, the upper layer of dead cells is shed from the surface. 2 to 3 billions of skin cells are shed everyday (they make up a substantial percentage of household dust).

The spaces between the epidermal cells are packed with natural fats (lipids). These fats help the top layer of dead skin cells regulate natural water loss. If they are removed by harsh soaps or detergents, or damaged by sunburn, the skin losses some of its ability to retain water and easily dries out.

The dermis

The base layer, the dermis, is mainly composed of a network of protein fibres; collagen and elastin. Collagen gives skin its strength and elastin keeps the skin supple and resilient. Collagen and elastin fibres are damaged by the effects of ageing, free radicals, pollutants, such as tobacco smoke and UV light.

By the age of 40, almost half the elastin present at birth is lost, resulting in lines, wrinkles and thin, sagging skin. The dermis houses the hair follicles, from which new hair is made and sensory nerve receptors, responsible for the sense of touch, heat, cold and pain. It is also rich in tiny blood and lymph vessels to provide oxygen and nutrients for cell growth and repair and removes wastes.

Sweat and oil glands 


Within the dermis are the sweat and sebaceous glands, whose secretions reach the surface through tiny openings or pores. Sweat glands mainly regulate temperature.

Sebaceous glands produce an oily secretion called sebum, which lubricates and waterproofs the skin and helps prevent moisture loss. Sebaceous glands are most concentrated on the scalp and face - particularly around the nose, cheeks, chin and forehead; hence these are usually the oiliest areas. Sebum production can increase temporarily during stress, before your period and around the menopause. As we get older we tend to produce less sebum and the skin becomes drier.

The acid mantle


Skin and hair are protected by a thin sticky fluid, the acid mantle formed from sebum, sweat and acidic secretions produced by skin 'good' bacteria such as Staphylococcus epidermis. The acid mantle created a hostile environment for 'bad' bacteria, which prefer an alkaline environment.

Any disruption to the acid mantle - e.g. : excess sunlight, poor diet, alkaline skin products and harsh soap - interferes with the protective outer layer of the skin and strips away the acid mantle. This leads to dehydration, roughness and irritation. Skin is left defenceless and susceptible to microbial invasion.

The normal acid mantle for skin and hair has a pH between 4.0 and 5.9. Once the pH rises above 6.5, bacterial invasion increases dramatically. Excess sunlight, poor diet, excessive sweating and strongly alkaline skin/hair products, soap or detergents can easily strip away the acid mantle. Citric and lactic acid are often incorporated into personal care products to help lower their pH and make them 'pH balanced'.

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