Q & A

Muse, Jul/Aug 2005 by Coontz, Robert, Spector, Rosanne

Q Why do we get shadows under our eyes when we lose too much sleep?

-Sarah P., age 13, Wisconsin

A The skin under our eyes is very thin, so it's easy to see through to the veins underneath. Those veins make the skin look purplish.

It gets even easier to see through the skin when we don't get enough sleep. That's because lack of sleep makes our skin paler and dries it out. I asked skin expert Brandith Irwin* about this, and she said: "The circles look worse after no sleep because the eye area doesn't rehydrate completely unless you lie down for seven to eight hours. Dehydration actually makes our skin look thinner, less elastic, and more transparent.

"Sleeping is best for those seven to eight hours, but if you're patient enough to lie still for that long without sleeping, I imagine this would alleviate dark circles too!"

-Rosanne

Q How does a water filter work? Wouldn't the water get dirty because of the charcoal?

-Juliette R., age 11, Illinois

A I sent your question to historyofwaterfilters.com, a Web site run by a commercial water-filter company. A water filter, their writer Vanessa Lausch explained, is made of tiny grains of charcoal or other materials. When water flows through it, those little chunks strain out solid stuff you'd rather not drink-much as big rocks in a river trap logs floating downstream. Most modern filters also do a more sophisticated trick. Their grains attract molecules of unwanted chemicals in the water, using positive and negative electric charges to trap the chemicals in the filter. Filters like these are used to remove chlorine from drinking water, something ordinary carbon filters can't do.

The grains don't get into the water because they're caught in a cage, like grapes in a sieve. Nothing is perfect, though, Lausch said. New filters sometimes contain grains small enough to slip through the mesh. When that happens, you have to rinse the filter until the water comes out clean.

-Robert

Have any questions you want answered? Send them to MUSE Q & A, 140 S. Dearborn Street, Suite 1450, Chicago, IL 60603, or send them by e-mail to muse@caruspub.com.

* Brandith Irwin is a dermatologist at the Madison Skin and Laser Center in Seattle, Washington.