Fall season is here!
While fall represents colorful leaves, pumpkins and a time of transformation, it's also time to start thinking about your skin, and how to prevent it from getting dry and dehydrated.
This article with discuss:
- Dry vs. dehydrated skin
- Fall weather conditions
- What is the skin barrier?
- Water is essential for the normal functioning of the skin
- What is best humidity level for skin?
- Sun exposure
Dry vs. dehydrated Skin
Dry or dehydrated skin appears dry, rough, and may scale and flake. It may also show premature signs of aging, like surface wrinkles and loss of elasticity.
Dry skin and dehydrated skin both develop from a lack of water and water-holding substances in the skin, called humectants. However, dry skin is also lacking fats that are found naturally in the skin, and these essential fats can be re-introduced through skincare products and dietary changes.
Dry and dehydrated skin can be relieved with the use of moisturizers and humectants, including glycerin, hyaluronic acid and natural moisturizing factors.
Fall weather conditions
It is broadly accepted that your skin barrier may be negatively affected by weather conditions (reviewed by Engebretsen et al, 2016).
As the temperatures start to get colder, the air gets dryer. Cold air has less moisture than warm or hot air, and cold air can be intensely drying on your skin.
Strong winds and UV damage from the sun can also strip moisture from exposed skin and disrupt the skin barrier.
Daily insults from the environment, such as low humidity, wind, and sun exposure, can lower the skin's water content, causing improper desquamation and the appearance of dry, flaky skin (Verdier-Sévrain et al, 2007).
What is the skin barrier?
Your skin barrier includes the outermost layers of skin, called the stratum corneum.
When your skin barrier is healthy, it feels and appears smooth, soft, and plump.
In contrast, a damaged skin barrier looks dry, rough, dull, and dehydrated, and may become irritated and inflamed.
Water is essential for the normal functioning of the skin
The water content of skin is remarkably high - the epidermis (the outer skin layer) contains more than 70% water, while its outermost layer, the stratum corneum has been shown to contain ~15 - 25% water (Warner et al, 1988; Caspers et al, 2001; Caspers et al, 2003).
Adequate hydration of the stratum corneum serves three major functions (Fowler, 2012):
- it maintains plasticity of the skin, protecting it from damage
- it contributes to optimum stratum corneum barrier function
- it allows hydrolytic enzymes to function in the process of desquamation
When the water content of the stratum corneum falls below 10%, scaling on the skin surface becomes visible (Rycroft, 1985).
Learn more: What is Dehydrated Skin?
When your skin is exposed to a dry environment, it could be more susceptible to mechanical stress (Engebretsen et al, 2016).
Studies in humans show a reduction in transepidermal water loss (TEWL) (a measure of the integrity of the skin's barrier function) with low humidity, alterations in the water content in the stratum corneum, decreased skin elasticity and increased roughness (Goad et al, 2016).
A study on dry facial skin found a higher dryness score with low temperatures, high wind speed and low humidity (Cooper et al, 1992) and as little as 15 min of cold and dry air has been proven to significantly decrease skin hydration (Roure et al, 2012). These data suggest that a reduction in temperature leads to a decrease in skin hydration and transepidermal water loss (TEWL), and that this effect is stronger when relative humidity is low (Cooper et al, 1992; Roure et al, 2012).
What is best humidity level for skin?
It is generally thought that humidity levels within occupied spaces should not exceed 60%, and when levels of humidity fall to around 30% or below, occupants begin to feel thermal discomfort (Goad et al, 2016).
Ultraviolet (UV) exposure from sunlight can also damage dry skin.
UV energy includes UVA, UVB and UVB radiation. Each component of UV can exert a variety of effects on cells, tissues and molecules (D'Orazio et al, 2013).
Chronic exposure to UV irradiation leads to photoaging, immunosuppression, and ultimately skin cancer (Matsumura et al, 2004).
UV exposure from the sun is still a concern during the fall months in Canada and proper sunscreen or sunblock should be worn when spending time outdoors.
Fall weather changes can lead to dry and dehydrated skin.
Cold temperatures, low humidity, wind and sunlight exposure can dry your skin and damage your skin barrier.
Dry skin appears dry, rough, and may scale and flake. It may also show premature signs of aging, like surface wrinkles and loss of elasticity.
It is important to protect your skin against fall weather.
Dry and dehydrated skin can be relieved with the use of moisturizers, humectants, and essential fatty acids.
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