Are there any permanent physiological side effects from tattoos?

Dear Matthew Alice:

I'm reading a mystery novel written in Japan in the 1940s that has a lot of information about tattoos in it. I wanted to check out one quote that seems pretty amazing. "When a person gets a major tattoo, there are also some permanent physiological side effects, including a perceptible change in metabolism....Having tattoos over a large area of the body radically lowers body temperature. Even on the most torrid summer day, tattooed skin is cool to the touch." Is this true?

-- Toni, North Park

I guess anybody'd be chilly, constantly stripping to show off a massive tat. That's one theory we scrounged up to explain your story. Current medical research suggests a tattoo itself has no permanent effect on your body's insides. The ink sits in the middle skin layer, the dermis, between the cells, and everything else continues to hum along just fine. When local medical experts were backed up against a wall and threatened in order to make them come up with a guess, a theory, anything, no matter how unlikely, to explain cold tattooed people, they whimpered something about how the occasional person will lose body hair permanently in the tattooed area. Without this heat-holding barrier, might the tattooed lady feel like a well-chilled carp? Perhaps it's a reaction to heavy metals used in 1940s-era tattoo inks. Might an overdose of chromium, mercury, cobalt, and manganese cause frost to form? Though far from satisfied, we took pity and let the doctors go. On the subject of weird tattoo lore, the only fact-like object we could dig up is a story of one heavily decorated patient who underwent magnetic resonance imaging in a hospital lab. The MRI somehow caused much burning, swelling, and discomfort when it interacted with iron oxide in the tattoo dye.