By Dr. Laurence Plumey
Cold weather, wind and home heating dry out the skin and leave it rough and flaky.
In other words, it is essential to protect and to moisturise it. Let's go back to basics, to understand better the nature of the skin and to understand its needs, in order to know how to take care of it and which products to apply.
The skin is a multilayer organ!
Around 3 mm thick, the skin contains 70% water (1). It protects us and allows us to be closely linked to our environment, thanks to the tactile sensations we can feel. It reaches a surface of 2 m2 and a weight of 4.5 kilos for adults Millions of glands, hair follicles, blood capillaries and nerve fibres run into the skin. Well, skin is a high-tech organ we must take good care of!
Skin is composed of 3 juxtaposed layers: epidermis (external), dermis (middle) and hypodermis (deep). Epidermis, the most exposed layer, protects us from external damages.
- Epidermis: above all a protection
It is rich in keratinocyte cells, which migrate towards the surface of epidermis and mutate into flat cells without nuclei, rich in keratin and insoluble in water. These cells are called corneocytes, held on each other, especially thanks to a sort of cement rich in keratin, lipids and oily acids and ceramids (2). This hydrolipidic film protects the skin and gives it flexibility. These corneocytes die and renew very fast; it is the natural desquamation phenomenon. In the epidermis, there are also melanocytes, responsible for the colour of the skin, Langerhans cells, that attack pathogenic bacteria, Merkel's cells, in contact with nerve termination, that participate to the touch function. This film is reinforced by sebum, a lubricant secreted by sebaceous glands, protecting the skin against drying (1,2).
Dermis: a function of support and nutrition of epidermis
Containing 80% water, the dermis is very rich in elastin and collagen fibres, embedded in glycoprotein gel. It is highly vascularised and 10 to 40 times thicker than the epidermis. It allows the skin to resist tensions and tractions and it gives it elasticity. It helps healing and thermoregulation. (3).
Hypodermis: can host fat cells
It is the deepest and the thickest layer of the skin. It can be more or less rich in fat cells, depending on the context and the location (abdominal, femoral). It also hosts the bulbs of the sweat glands: we have 2 to 5 million in our body. They produced sweat: 400 ml per day minimum and up to 1 litre per hour! (4,5)
How to protect your skin during winter
During winter, you skin hurts: cold weather tightens the pores and reduce sebum production, therefore decreasing the quality of the hydrolipidic film. Cold weather is often dry, as is the air in heated houses. That's why it decreases moisturising capacities by exterior environment. That is why the skin becomes dry, tensed and it can develop pruritus.
Here are 8 recommendations to preserve your skin, on the face and on the body:
1 - Every morning and every night, cleanse your skin to remove impurities and apply an emollient, moisturizing and lipid-rich cream.
2 - Avoid taking very hot showers, as they are an additional irritant for your skin.
3 - During showers, use hydrating soap with oils, shea butter, glycerine, etc.
4 - After a shower or bath, dab your skin with a towel rather than rubbing it, and apply your moisturising lotion or cream.
5 - Scrub regularly (once every 15 day in average) to remove dead cells from face and body. Then, use a emollient cream, because its lipids will enter the skin much better once it is free from dead cells.
6 - Place humidifiers in he rooms of your house, in order to maintain a certain humidity quota. Aerate your house everyday.
7 - Protect your lips as well, with a moisturising balm.
8 - And do not forget your hands: avoid contact with dishwashing detergent, especially under very hot water, Apply a highly moisturizing cream on your hands everyday.
To conclude, skin is too precious to let it be damaged during winter: let's protect it with high quality emollient creams.
Sources:
1. Gougerot-Schwartz A. Hydratation et produits hydratants. EMC , 2000, 50 – 160 - B.10
2. Structure de la peau. Cours de Formation “Comprendre la peau. Histologie et histophysiologies de la peau et de ses annexes. Ann.Dermatol.Venereol, 2005, 1342, 8S5.48
3. Barry M.Popkin and coll. Water, hydration and health. Nutrition Reviews, 2010, Vol 68 (8) : 439-458
4. Jequier E, Constant F. POurquoi faut-il boire de l’eau ? Pour maintenir la balance hydrique. Cah Nutr Diet, 2009, 44, 190-7.
5. Sawka MM and coll. Human water needs. Nutr Rev, 2005 : 63, 530-9