As you get older your veins can lose elasticity, causing them to stretch. When this happens, blood that should be moving toward your heart may flow backward. Blood pools in your veins, and your veins enlarge and become varicose. The veins appear blue because they contain deoxygenated blood, which is in the process of being recirculated.
Get the top 8 most frequently asked questions about varicose veins and their treatment in this free guide.