For other people, however, hair loss does not stem from autoimmune issues. Plenty of factors can play a role, including hairstyles that pull tightly, stress and damaging hair treatments. Nutritional deficiencies can cause alopecia, as can hormonal changes or even stressful life events. Hereditary-patterned baldness is common, too.
Article source: https://www.huffpost.com/entry/what-to-know-alopecia_l_6241b899e4b0ab00739d3b23