There are many reasons for hair loss like aging, certain medical conditions and medications, environmental effects, excessive smoking, genetic factors, hormonal imbalance, nutrient deficiencies, scalp infections, too much stress, and use of wrong hair products. Experts say it is normal to lose about 50-100 strands in one day. However, if you are losing more than that, you need to do something to prevent it from resulting into bald spots or baldness.