Your nails can reveal surprising things about your internal health.
A doctor now warns that even small changes in your nails could be an early – and often overlooked – indicator of advanced lung cancer.
Here are the some key signs to watch for.
Downward-curving nails

One of the most distinctive warning signs is when your nails start curving downward, resembling an upside-down spoon.
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This condition, known as "clubbing", is often linked to a lack of oxygen in the blood and may appear in 5–15 % of lung cancer patients.
Thickened fingertips

If your fingertips appear rounder or more swollen than usual, it could be caused by increased blood flow due to hormonal-like substances released by tumors in the lungs.
Spongy nail beds

According to lung specialist Dr. Dawood Johari, the area beneath the nails may feel soft or spongy to the touch.
This could be due to fluid buildup caused by changes in blood vessels related to the cancer.
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Redness and warmth in fingertips

Unusual redness or heat in your fingertips may be a subtle sign of inflammation linked to lung cancer.
This can occur due to blood vessel dilation caused by chemical substances from the tumor.
Chronic cough lasting more than two weeks

While not a nail symptom, a persistent cough is one of the most common early warning signs of lung cancer and should not be ignored, especially if it appears along with nail changes.
Unexplained weight loss and fatigue

Sudden weight loss or ongoing fatigue without a clear reason can indicate underlying cancer.
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When paired with nail abnormalities, this combination may strengthen the case for getting a medical checkup.
Hoarseness or voice changes

A hoarse voice or unexplained changes in vocal tone could suggest that a tumor is pressing on nerves in the chest. Nail changes at the same time should raise concern.
Shoulder pain that worsens at night

Unexplained shoulder pain, particularly if it intensifies at night, could be caused by lung cancer affecting nearby nerves.
Accompanying nail deformities could provide an additional clue.
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Drooping eyelids and vision changes

Some rare types of lung cancer may lead to neurological symptoms, including drooping eyelids or blurred vision.
If these occur with noticeable nail changes, immediate medical attention is advised.
Dark streaks or bleeding under the nails

Dark lines, unexplained bruising, or bleeding under the nails may not only point to skin cancer or blood disorders but could also be a sign of lung cancer or other malignancies.
Any of these symptoms should prompt further investigation.
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This article is based on information from Sanook.com.