Note: Readers commenting under today's Friday Happy Hour post brought up an age old question: "Is blood blue when it's inside the veins?" Matt Soniak kindly put together this response. Why do veins ...

The blood inside your veins is dark red. So, many people wonder why veins look green or blue through the skin instead of red. Veins are types of blood vessels. The other blood vessel types are ...

Spider veins and varicose veins are caused by weakness or damage in the veins. Varicose veins are typically larger, but both are externally visible. Both commonly occur in the legs. Spider veins can ...

Varicose veins are large, raised, swollen blood vessels that twist and turn. They usually develop in the legs and can be seen through the skin. They result from a weakening in the blood vessel wall or ...

David Irving does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their ...