Soft, brittle nails and the absence of the lunula (the crescent-shaped "moon" at the base of the nail) can be indicative of hyperthyroidism, an overactive thyroid gland.
Hyperthyroidism can cause changes in the nails and skin due to the increased metabolism and hormonal imbalance. Some common nail changes associated with hyperthyroidism include:
1. Softening of the nails
2. Brittle or fragile nails
3. Nail thinning
4. Absence or reduction of the lunula
5. Nail ridging or grooving
However, it's essential to note that these symptoms can also be caused by other health issues, such as:
1. Nutritional deficiencies (e.g., iron, zinc, or biotin)
2. Skin conditions (e.g., eczema, psoriasis)
3. Aging
4. Nail trauma or injury
5. Other hormonal imbalances
If you notice these symptoms, it's crucial to consult a healthcare professional for a proper diagnosis and treatment. They will evaluate your overall health, perform necessary tests, and determine the underlying cause of the nail changes.

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