White dots on arms and legs may be caused by white furfury, senile white spots, vitiligo and other factors. 1. White chaff rash: related to malnutrition, vitamin deficiency and other factors, can lead to white dots on the face, arms or legs, usually no self-conscious symptoms, usually do not need special treatment, may be recovered on their own. 2. old age white spots: with age, some of the elderly in the arms and legs will appear old age white spots, usually soybean size white spots, no conscious symptoms, usually does not affect the health of the body, can not be dealt with. 3. Vitiligo: may be related to genetic, neuropsychiatric factors, can lead to arms, legs and face and other parts of the white dots, the area may gradually increase. White dots on the arms and legs, and accompanied by other abnormalities, or a gradual increase in the number of white dots, it is recommended to seek medical attention for examination and treatment.