Why do some people's blood veins poke out of there arm ?

I have noticed it's usually found on guys
Answer:
Some because they have low amount of fat. Some others because their muscle demand more oxygen (weight-lifters) so the veins (and arteries) enlarge to transport nutrients more efficiently.

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tends to be in fitter people - they have less fat under the skin, which normally hides/covers veins.

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My son is a runner, i notice his arm veins bulge after a long run.

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they could have high blood pressure

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i aint sure why, and wonder that myself,, i am a pretty large lady and no one can find a vein in my arm, when i get my blood drawn, and they always have to use the top of my hand,, it may have to deal with how much fat a person has,, not real sure

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My boyfriend and I are both this way.He is very fit and lean. There's not much fat on his body, so his veins are directly under the skin as opposed to hidden under the fat.Mine stick out because I'm naturally very skinny and have no fat on my arms.So the basic answer is because there's not any fat to keep the veins concealed.

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I'm going with low body fat index. My veins stick out and I'm on the light side, do not have high blood pressure, in fact mine is on the low side of that. I've always been kinda scrawny and always had visible veins, never had a problem giving blood, ha, ha.

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