1. When your body sheds excreted fats and disintegrating debris from your cells (known as sebum), it removes them via your hair follicles. Learn more about how sebum forms.
  1. Sebum is gross but crucial -- it moisturizes and waterproofs your hair and skin. Learn more about sebum's role in your skin and hair.
  1. Though you can wash your hair too much, washing it not enough can allow bacteria to build up, provoke an allergic reaction and cause your head to break out in acne. Learn more about acne vulgaris.
  1. Frequent shampooing can actually be counterproductive. Because you're trying so hard to get rid of sebum, your body reacts by producing even more of it. Learn more about shampoo frequency.
  1. If you're looking to conserve water but still clean your hair, try using dry powder or baking soda with a raw egg and lemon juice. Learn more about how to clean your hair naturally.

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