These are generally considered asymptomatic, and quite common. You don't see them in some people, due to hair covering them or higher body fat.
Some suggestion has been that they are more prominent in people with hypertension, but they will become more prominent after a few drinks, like any other vein does.
If you're concerned, see your GP, but generally they are nothing to worry about, unless of course you have hypertension.
BD
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