The lightest bump can cause a dark bruise, and if I rub against any metal, paper, etc, the skin on my arms can bleed heavily. All of the rest of my body skin is normal and doesn't do this? Any suggestions for causes and prevention of future skin issues. Was exposed to the sun as a child and teenager, but minimal exposure since age 30. Light skinned, blond and green eyes heredity. Skin is typically see thru, and most of the nearer blood vessels are visible on all of my skin. Small veins in arms, when giving blood.