By Dr. Mehmet Oz
Your body has clever ways of signaling health trouble. Here's a guide to what your hue says about you.
Few people get worked up over the occasional bruise. We know from experience that a purplish spot isn't usually cause for alarm and, in time, will clear up on its own -- a classic case of the wait-and-see approach making sound medical sense. But other discolorations that may appear harmless can serve as warning signals for serious diseases, like diabetes, skin cancer, and autoimmune disorders. The sooner you pick up on the clues, the faster you can take the right steps to getting and staying healthier.
Pay attention to the color of your tongue. If it becomes a bright, beefy red (the change can be subtle, but it will be noticeable), you may be low on vitamin B12. This vitamin is essential for making the red blood cells that carry oxygen throughout your body and plays a vital role in maintaining brain function. While researchers aren't sure why a B12 deficiency affects the tongue, you may develop neurological problems, including dementia, if your levels stay low for too long.
Protect Yourself: Meat and dairy products are rich in B12, so if you're a vegetarian or vegan, you may have a harder time reaching your daily allowance. Make sure to take a multivitamin, and consider eating fortified cereals for breakfast (some offer 100 percent of your recommended daily value of B12 in one serving).
When pigment-producing skin cells die, you're left with white spots that retain the same texture as the rest of your skin but lack melanin. This condition, known as vitiligo, affects up to two million Americans, the majority of cases occurring in people under 40. It's most noticeable where skin is usually a bit darker -- hands, feet, arms, face, lips. But it can also occur in the armpits, nostrils, and even on your scalp. Researchers think vitiligo may be the result of an autoimmune disease that causes your body to mistakenly attack its own cells; it's associated with thyroid disease and Addison's disease (in which your adrenal glands stop producing enough of the hormones that help control everything from your immune response to your sex drive).
Protect Yourself: While there's currently no way to prevent most autoimmune diseases, you may be able to treat your white patches with corticosteroid creams, which have been shown to be effective in restoring some pigmentation. And I can't stress how important it is to wear sunscreen. Without melanin, your skin is at much higher risk for sunburns. To conceal the spots while shielding your skin, opt for a tinted moisturizer with at least SPF 30.
Elbows, knees, hands and feet
The appearance of soft, yellowish bumps (called xanthomas) on your body -- particularly on your elbows, knees, hands, and feet -- can indicate dangerously high cholesterol levels, which increase your risk for cardiovascular problems including heart disease and stroke. These growths, which are painless and can range from very small to wider than three inches, are actually fat deposits that build up under the skin, often when an excess amount of lipids -- due to either a genetic condition or a high-fat diet -- accumulates in your blood.
Protect Yourself: Nearly 54 million women have high or borderline-high cholesterol, with 19 million falling in the high range. But while maintaining a healthy diet can certainly help keep cholesterol under control, when it comes to lowering your levels of LDL (the bad kind), exercise is critical. A 2009 study in the Journal of Lipid Research found that women who walked one extra hour or jogged an additional 30 minutes per week lowered their LDL levels by 3 percent or more. They also saw an increase in their levels of HDL (the good kind). Even better news: Once cholesterol is back in a healthy range, xanthomas may start to clear up.
Neck, armpits and groin
Dark, velvety patches found in your armpits and on your neck and groin are likely acanthosis nigricans. This slow-developing skin condition, which is more common in overweight and obese adults, can be a sign of type 2 diabetes. Researchers believe that insulin resistance (which causes high blood sugar and can lead to type 2 diabetes) can send some skin cells into overdrive, increasing skin thickness and darkening pigment.
Protect Yourself: To help prevent diabetes, pay particular attention to your diet. Filling up on high-fiber foods (think oatmeal, beans, and broccoli) can slow the body's absorption of sugar and, as a result, may keep blood sugar within a healthy range. One study found that prediabetics who consumed the most fiber were 62 percent less likely to develop full-blown diabetes than those who consumed the least.
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.