Dr. Oz: A Guide to Your Body's Color Coding

Nails

The next time you do your monthly body check for new moles or dark spots, be sure to examine your nails. Dark, vertical bands (they're typically brown but can also appear blue or black) under your nail beds—most commonly on your thumb or big toe—could be a type of melanoma. While melanoma accounts for less than 5 percent of skin cancers in the United States, it's responsible for 75 percent of skin cancer deaths because it often goes undetected. And your risk is greatly affected by the color of your skin: Among Caucasians, only 2 to 3 percent of melanomas are found under the nail, but that number is as high as 40 percent among the rest of the population. Malignant melanomas can be easily treated if caught early, so make an appointment with a dermatologist if you notice any dark bands on your nails. She'll do a biopsy if she suspects cancer.

Protect Yourself: As with all skin cancers, prevention is key. When you apply sunscreen in the morning, take the time to coat your nails and cuticles. Maintaining strong nails can also help shield the skin beneath, so keep them well moisturized to prevent cracking and flaking. And if you use nail polish, keep in mind that some brands now offer added UV protection.

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