Pathological reasons are generally varicose veins or emotional excitement, which leads to the obstruction of subcutaneous venous blood return and venous vasodilation.
Physiological reasons are mainly thin body or long-term heavy physical labor, less subcutaneous fat, obvious veins and blood vessels under the skin, and symptoms of exposed veins and veins.
Therefore, the exposure of the blue veins may be due to the symptoms of weight loss and subcutaneous fat loss, but it cannot be said for sure that this is the reason.