Blood is thicker in Canada

Heymatt:

Mt boyfriend is from Canada, and he claims that when people move from a cold climate to a warm climate, their blood gets thinner and they are more sensitive to cold. Huh?

-- Terra, San Diego

So if you live in the Yukon and cut yourself, your blood globs out like toothpaste? Weeeeeeellll, I don't think so. But blood does help control body temperature. When your boyfriend is in frosty Canada, the teeny capillaries in his skin contract to help conserve his core temperature. The Canada-to-California move requires your vascular system to adjust to continual warm weather by forcing blood into surface capillaries so excess body heat can be radiated away. It can take from weeks to months for your body to adjust to these changes. People who live at high altitudes require more oxygen-carrying red blood cells. Maybe we could say they have "thicker" blood, but I'm afraid boyfriend is just turning into a Southern Calfornia wuss.