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Why Are My Toenails Yellow?

Written by 
Meghan Rabbitt
Canyon Ranch Reviewer: 

Q: My toenails have a yellow hue that won’t seem to fade. Why is this, and what can I do to get rid of the discoloration and keep it from coming back?
 

A: One of the most common reasons for yellowing nails, whether on hands or feet, is wearing nail polish for an extended period of time; darker polishes are often the culprit, due to stronger leftover dyes that stain your nails. Plus, many polishes contain formaldehyde, a chemical that can cause yellowing when it reacts with the keratin protein in your nails. Removing the polish and letting your nails “breathe” for a few weeks with no polish can help them return to a normal hue. When you do paint your nails again, try formaldehyde-free polishes, or a light color to avoid deeper dyes. If the discoloration persists or you don’t regularly wear polish, though, there could be a number of other reasons you’re noticing a yellow tinge, including: 

  • Smoking Over time, the tar and nicotine in smoke—from holding a cigarette—can stain your nails.
     
  • A Fungal Infection Fungus thrives in warm, dark, moist environments, which makes your toes a prime location for fungi to hang out. After all, you probably wear shoes (and sometimes socks) all day, which trap moisture. What’s more, poor circulation in your feet, which can be due to a number of issues—among them, a lack of exercise, obesity, diabetes and high blood pressure or cholesterol—makes it tougher for your body to get rid of an infection once it's started.
     
  • Diabetes Blood sugar imbalances can cause glucose to attach to collagen proteins, the structural tissue in nails, which transforms the nail shade from normal to yellow.
     
  • Genetics If your doctor has ruled out a fungal infection, you could have yellow nail syndrome, which—as its name implies—is characterized by nails that are yellow in color, but also grow slowly, lack a cuticle, and/or nails that are loose and can become detached from the nail bed. Although experts don’t know exactly what causes this condition or what cures it, they do know it has a genetic component.
     
  • Aging As we get older, blood circulation and cell turnover slow, which can lead to brittle, weak nails. This lack of circulation to the nail bed can cause the skin-colored hue you’re used to seeing change to a yellow tint.  
     
  • Lymphedema This condition is caused by a blockage in your lymphatic system (part of your circulatory system), which prevents lymph fluid from draining well and causes swelling, typically in an arm or leg. As a result, your affected limb becomes particularly vulnerable to infections, including the fungal kind that can lead to yellow nails.
     

Although you may want to cover up your yellow nails with polish, try to resist the urge. If the weather allows, opt for sandals, or at least walk around your house barefoot as much as you're able. And consider these other solutions to help return your nails to a normal hue:

  • Oral Antifungal Medication If you suspect a fungal infection, see your doctor or a podiatrist to confirm the diagnosis. If it is nail fungus—or if you have diabetes or experience pain or discomfort in your toenails—your doctor may prescribe an oral antifungal medication that you’ll typically take for as many as 12 weeks. Don't expect quick results; it can take up to six months to completely eliminate a fungal infection.
     
  • Topical Treatments Your doctor may prescribe an antifungal gel, cream or “polish” that you actually paint onto your nails like a regular nail lacquer. Keep in mind that this treatment tends to work better on mild or moderate cases of nail fungus, and may be prescribed along with oral medications. Tea tree oil is another topical option for treating fungus. Apply one or two drops of 100 percent pure tea tree oil to your discolored nail(s) once or twice a day; try to avoid getting the undiluted oil on your skin, which can be irritating.
     
  • Vinegar Foot Soaks Some studies have shown that vinegar may inhibit the growth of certain bacteria. Pour one part vinegar to two parts warm water into a small tub and soak your feet for 15 minutes, two to three times a week. Be sure to rinse your feet well and dry them thoroughly after the soak. Letting your nails sit in a tub of freshly squeezed lemon juice can also help; the acidity has a bleaching effect.
     

As your yellow nails are healing, don’t pick at them—even if they separate from the nail bed (a condition called onycholysis). You’ll also want to wash your hands thoroughly if you happen to touch an infected nail, as nail fungus can spread easily.

To prevent your nails from turning yellow:

  • Take a break from polish. As mentioned above, you can try going “au naturel” for a couple of weeks in between polishes (meaning without any color; clipping and buffing nails will help you maintain a clean look). Nail lacquers can not only lead to nail discoloration, but they also trap moisture in the nail bed, which can lead to fungal infections.
     
  • Wear clean, dry socks. To help avoid nail fungus, be sure your socks are clean and dry, which means you may have to change your socks in the middle of the day if your feet tend to sweat.
     
  • Dry your feet well. If your daily routine includes jumping out of the shower and toweling off in 30 seconds before getting dressed, you’re probably not drying your feet thoroughly before putting on your socks and shoes. Be sure to spend some time toweling them off completely—yes, that includes between your toes—after bathing.
     
  • Clip your nails regularly. Trim your nails straight across and use an emery board to file down rough edges and any nails that are especially thick.
     
  • Take action right away. At the first sign of discoloration—usually a little white or yellow spot will appear under the nail—schedule an appointment with your doctor. If you treat a nail fungal infection immediately it can be easier to contain and less likely to become a recurring problem.
Reference(s) 
Mayo Clinic
About the author 
Meghan Rabbitt is an editor and writer whose work has been published in Women’s Health, Fitness, Shape, Runner’s World, Prevention, Parents and Weight Watchers.