Is it unhealthy for a teenager to have visible veins in their legs?

Varicosities: No, definitely not. These are called varicosities and they shouldn't cause any problems unless they are very disfiguring and causing psychological stress to the teenager.

Sometimes: Teenagers can have varicose veins which can cause other symptoms such as pain, aching, heaviness and fatigue in the legs. Venous insufficiency can also cause cramping, restless legs syndrome and even skin changes in the lower extremities such as eczema.

It certainly can be: It is not rare for teenagers to develop varicose veins. If this occurs, i certainly would not consider it to be healthy. Veins like this can symptoms like dr. Hansen mentioned and if a tennager has varicose veins with any of these symptoms, they should be evaluated.