I recently visited my hometown, Shillong in the north eastern part on India during the last few days of November and it was already cold especially at night. The water was freezing cold as well.
The first thing I noticed was my skin felt extra dry, with visible patches of dry spots. My lips were constantly chapped and I could literally write on the skin on my legs. These skin changes were happening with everyone. My family members and I had patients from back home that all complaint that their skin felt tight.
So why does this happen in winter?
To understand this, we will have to do a deep dive into how our skin functions in an optimal environment.
As you can see the protein filaggrin plays an important role in hydrating the skin, protection against UV rays and maintaining a healthy skin barrier. Individuals with mutation in the gene encoding filaggrin protein are more predisposed to developed eczemas and other allergic conditions such as asthma. Studies have found that low humidity and low temperature causes a decrease in the amount of natural moisturising factor (NMF) in the stratum corneum and this causes decrease in skin hydration. This results in the subjective feeling of dry flaky skin during winters.
Animal studies also show that when the skin is exposed to low humidity, a reactive pathway favouring pro inflammation is activated within 24 hours. What this means clinically is that, the skin maybe more sensitive to ingredients present in skin care products during winters.
Certain skin conditions can worsen during winters. Individuals suffering from eczema, psoriasis, rosacea, cold urticaria should be careful not to be exposed to cold weather, water and to aggressively take care of the skin by moisturising and being gentle with their skincare.
Skin changes associated with using radiation heaters during winters
Homes in Shillong do not have central heating and rely on the use of radiation heaters or coal stoves to keep them warm. There are certain skin changes that can be associated from exposure to such infrared radiation.
Erythema ab igne/ Toasted skin syndrome/Fire stains
Reticulate (lacy pattern) erythema (redness) and pigmentation on the skin caused by chronic and repeated exposure to infrared radiation from heaters, wood or coal stoves. This has recently been described to be seen on the thighs of people with prolonged contact with laptops.
Though the condition is benign and resolves when the heat source is removed, the pigmentation can be permanent for some and in rare instances skin cancers such as squamous cell carcinoma or merkel cell carcinoma can develop.
Avoid sitting too close to the heat source (heater or stove)
Wear protective clothing to prevent direct exposure of the skin to the heat radiation
Remove the most heat source the moment redness develops on the skin
Seek a dermatological examination if a non-healing ulcers or wound develops over the skin where the pre-existing erythema or pigmentation was.
Worsening of Melasma
A multi centric cross-sectional study from India found a significant and positive association with the duration of heat exposure and the severity of melasma
If you suffer from melasma, avoid sitting too close to the heat source and always remember to wear a broad-spectrum sunscreen even when indoors.
Illustrations done by Alexandra Kristin Mawlong