White spots inside the nails may be caused by malnutrition, trauma, fungal infections and so on. 1. Malnutrition: If you are usually picky about what you eat, gastrointestinal absorption obstacles, resulting in a lack of calcium, zinc and other trace elements, malnutrition occurs, it may also make white spots appear on the nails. 2. Trauma: If the nails are accidentally traumatized, white spots may also appear on the nails; 3. Onychomycosis: Onychomycosis is a relatively common nail lesion, mainly due to fungal infections, which usually results in white spots on the nails, and may also cause the nails to become brittle, thickened and yellowed. Nails with white spots may also be caused by other reasons, specific recommendations to the regular hospital for relevant examinations, a clear diagnosis, and then according to the situation using the appropriate solutions.