Thicker and thicker nails may be caused by fungal infection, heart failure and psoriasis. 1. Fungal infection: after the nail is infected with fungus, the reproduction of fungus will lead to the thickening, deformation, discoloration and brittleness of the nail plate, which will lead to the phenomenon of thicker and thicker nails. 2. Heart failure: heart failure patients with reduced myocardial ejection function, resulting in insufficient blood supply to the endings of the limbs, poor blood circulation, and accumulation of metabolic wastes, leading to the phenomenon of thickening and deformation of nails. 3. Psoriasis: Psoriasis can damage the nail hypodermis and distal nail bed, resulting in symptoms of hyperkeratosis and thickening. If the phenomenon of thicker and thicker nails occurs, it is necessary to go to the hospital in time to clarify the cause, and the doctor will issue an individualized treatment plan according to the situation, so as to avoid delaying the condition.