One of the most common causes of visible veins is a low body fat percentage. People who are lean or very muscular generally have thinner skin, which makes veins more apparent. This phenomenon is even more pronounced in people who engage in regular physical activity, particularly weight training or high-intensity exercises, as these temporarily increase blood flow, causing veins to dilate and become more visible....
Another natural factor at play is aging. Over the years, skin loses collagen, a protein essential for its firmness and elasticity. As it thins and loses elasticity, internal structures like veins become more visible, especially on the hands, where the skin is naturally delicate.
