Thick bunion nails may be related to bad habits, but also may be the emergence of gray nails, nail psoriasis and other diseases. 1. Bad habits, patients often wear tight shoes leading to nail compression, repeated friction, which can lead to thickening of the nail plate, appearing foot bunion nails are very thick. 2. Gray nails, also known as nail fungal disease, clinical fungal infection of the nail plate and surrounding tissues, may lead to abnormal proliferation of nail tissues, nail plate thickening, the symptoms will also be accompanied by color changes. 3. Nail psoriasis, nail psoriasis patients may appear nail plate thickening, under the nail hyperkeratosis phenomenon, resulting in nail plate thickening, at the same time may appear lobular hemorrhage, thimble-like changes in the nail plate lesions. If there are obvious symptoms of nail thickening, it is recommended to consult a doctor in time for examination and treatment.