What are the causes of severe hair loss and shedding?

The causes of severe hair loss are complex and varied, mainly including: 1. **Genetic factors**: Individuals with a family history of hair loss are more prone to experience hair loss issues, as genetics play a significant role in hair loss. 2. **Hormonal changes**: Fluctuations in hormone levels, especially androgens, may affect the health of hair follicles and lead to hair loss. 3. **Unhealthy lifestyle habits**: Long-term late-night stays, irregular eating habits, smoking, and excessive alcohol consumption can negatively impact hair health. 4. **Medical conditions**: Diseases such as seborrheic alopecia, folliculitis, and anemia can cause significant hair loss. 5. **Psychological stress**: Prolonged states of tension, anxiety, or other negative emotions may trigger hair loss.