Warning Signs: Your Fingers and Nails Can Reveal Health Issues 

1. Clubbed Fingers as an Early Sign of Lung Cancer: Clubbed fingers, characterized by swelling and thickening of the fingertips, can be an indication of lung cancer. This condition is caused by tissue hypoxia, resulting in blood vessel dilation and tissue growth. Approximately 1.6-9.4% of lung cancer patients show clubbing symptoms. 

2. Abnormal Finger Symptoms and Possible Underlying Conditions:
 - Numbness: Numbness in the hands may signify conditions such as cervical spondylosis, diabetes, or hypertension. 
- Tremors: Trembling fingers can be a sign of heart disease, thyroid hyperactivity, or nervous system damage. 
- Swelling: Swollen fingers can result from various ailments, including arthritis, excessive salt intake, or specific diseases like Raynaud's phenomenon. 
- Discoloration: Changes in finger color may indicate conditions like Raynaud's disease, ischemic necrosis, or blood infections. 

3. Clues from Nail Abnormalities: 
- Changing Moon Shape: Sudden changes in the shape or quantity of the moons on your nails may warrant a medical check-up. 
- Black Lines: Black lines on the nails could be a sign of potentially malignancy-prone melanocytic nevi. - Nail Pitting: Pitting can indicate various conditions, such as zinc deficiency, parotiditis, or diabetes. 
- Terry's Nails: Whitening with a narrow, pink band near the fingertips could hint at underlying liver disease or diabetes. 
- Yellowing and Thickening: Yellowing and thickening of the nails may indicate yellow nail syndrome, lung disease, or lymphedema. 
- Spoon-shaped Nails: Known as koilonychia, this condition may be caused by iron deficiency or malnutrition.

Remember to pay close attention to the health of your fingers and nails. If you experience swelling, numbness, tremors, or abnormal nail changes, seek medical advice promptly.