Illustration: Shout

Of all the anxieties a woman faces when diagnosed with cancer, one is especially distressing, because it strikes at her dignity: the potential loss of her hair. But since 2004, more than 1,000 women in the United States have found an alternative—a cap that can protect hair follicles from chemotherapy.

Filled with a gel chilled to minus 22 degrees Fahrenheit, the Penguin Cold Cap (imagine a helmet-shaped ice pack) is worn before, during, and after chemo sessions to slow the rate at which cells in the scalp absorb blood, thus reducing the amount of toxic chemicals that can reach hair follicles (which happen to be just the type of fast-growing cells that cancer drugs target). A 2008 trial found that 85 percent of chemo patients on two drugs (and 66 percent of patients on any chemo regimen overall) experienced minimal hair loss thanks to the Penguin. Still, the cap isn't FDA approved: "There's a possibility that cancer cells are hiding in your scalp, and those cells could escape," explains Jeffrey H. Margolis, MD, one of the doctors who ran the trial. "But the number of people with isolated scalp metastases is less than 1 percent."

It costs $500 a month to rent the caps from penguincoldcaps.com. To breast cancer survivor Shirley Billigmeier, the price was worth it: "When I realized I could save my hair, I thought, "I can fight this thing with my whole self."

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