Sleeping on your side causes the skin of the décolleté to fold, which leads to the formation of permanent wrinkles over time.

noli's read

The idea that repeated mechanical forces influence wrinkle formation is widely recognized in dermatological literature. Studies, notably those published in the 'Journal of Cosmetic and Laser Therapy' (observational studies on sleep wrinkles), confirm that 'sleep wrinkles' are distinct from expression lines and are caused by prolonged skin compression. It is accurate that gravity and the lateral position create repetitive skin tension on the décolleté. However, stating that this becomes inevitably permanent simplifies a complex process. Skin aging actually depends on a combination of factors: genetics, UV exposure (photoaging), collagen loss, and skin quality, not posture alone. The mechanical aspect is therefore a real contributing factor, but it is often overestimated in relation to major environmental and biological factors.

the sources

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