White toenails, a condition known as leukonychia, are a common observation. This discoloration can appear as spots, streaks, or affect the entire nail. While often harmless and temporary, white toenails can sometimes signal an underlying health concern. Understanding the causes helps determine if it’s a cosmetic issue or requires medical attention.
Common Reasons for White Toenails
A frequent cause of white toenails is a fungal infection, specifically superficial white onychomycosis. This infection often presents as flaky, white patches or pits on the nail surface, sometimes making the nail appear soft, dry, or powdery. These fungi, known as dermatophytes, can lead to discoloration, thickening, and crumbling of the nail if the infection progresses.
Trauma or injury to the toenail is another cause for white discoloration. Activities like stubbing a toe, wearing ill-fitting shoes, or aggressive pedicures can damage the nail matrix, where the nail grows from. This damage can result in white spots or lines (punctate or striate leukonychia) that will grow out with the nail over several months.
Cosmetic factors also contribute to white toenails. Prolonged use of nail polish, especially those containing certain chemicals, can dehydrate the nail surface and lead to white, chalky patches known as keratin granulations. These can also arise from reactions to nail products or removers. Giving nails a break from polish allows them to rehydrate and often resolves this type of discoloration.
Underlying Medical Conditions
Beyond common causes, white toenails can occasionally be a manifestation of significant systemic health issues. Certain systemic illnesses, such as kidney disease, liver disease, heart failure, or diabetes, can impact nail appearance. For example, “Terry’s nails” are characterized by a mostly white nail with a narrow pink or brown band at the tip, often associated with liver failure, congestive heart failure, or diabetes.
Severe nutritional deficiencies, though rare, might also affect nail health, leading to white lines or spots. Deficiencies in minerals like zinc or iron, or a protein deficiency, can cause the majority of the nail to appear white, except for the tip. However, other symptoms of these deficiencies would be present before nail changes become noticeable.
Skin conditions such as psoriasis or eczema can also impact the nails, leading to various changes including white discoloration. Psoriasis can cause pitting, crumbling, or white patches on the nail, along with potential thickening or separation from the nail bed. Eczema can similarly lead to nail changes, including discoloration.
Certain medications, particularly chemotherapy drugs, can have side effects that manifest as changes in nail color, including white bands or discoloration. Exposure to toxic heavy metals can rarely cause white spots on the nails.
Recognizing When to See a Doctor
It is advisable to consult a healthcare professional for white toenails if the discoloration is persistent or worsens over time, especially if white areas spread or the nail texture changes. This includes situations where the white patches do not improve as the nail grows out.
The presence of associated symptoms is another indicator to seek medical attention. Pain, swelling, redness, a foul odor, or discharge around the nail suggest a possible infection or inflammatory condition. Changes in nail thickness or shape, such as crumbling or lifting from the nail bed, also warrant evaluation.
If multiple toenails are affected by white discoloration, particularly in a symmetrical pattern, it warrants medical evaluation. This pattern can suggest an underlying systemic issue rather than a localized problem. If there is no obvious cause, such as a recent injury or cosmetic product use, a doctor’s visit can help determine the root cause.
Individuals with existing chronic medical conditions like diabetes or a weakened immune system should be vigilant. For these individuals, even seemingly minor nail changes can indicate a more serious complication or infection that requires prompt treatment.
Professional Diagnosis and Treatment
When consulting a healthcare professional for white toenails, the diagnostic process begins with a visual examination of the affected nails and a review of the individual’s medical history. The doctor will inquire about recent injuries, chemical exposure, and any other symptoms present.
To identify the cause, diagnostic tests may be performed. For suspected fungal infections, a common procedure involves taking nail clippings or scrapings for laboratory analysis, such as a potassium hydroxide (KOH) preparation or a fungal culture. In some cases, a nail biopsy might be necessary to rule out other conditions.
Treatment approaches for white toenails depend on the identified cause. If a fungal infection is diagnosed, antifungal medications, available in topical creams or oral pills, are prescribed. For trauma-induced white spots, the discoloration often resolves naturally as the nail grows out, though this can take several months.
When an underlying medical condition is responsible, treating that root cause is the primary focus, which may lead to improvement in nail appearance. For white toenails caused by cosmetic products, avoiding the irritant and allowing the nails to breathe often resolves the issue. General prevention tips include maintaining proper nail hygiene, such as keeping feet clean and dry, trimming toenails straight across, and wearing well-fitting shoes to prevent injury and reduce the risk of infection.