As long as you’re using the right products in your hair, you can shampoo your hair every day, 100 times a day if you want, without any side effects. Again, only if you are using the right products.
Using a regular use or mild shampoo that’s best for your hair-type will keep your hair in very good condition. For men, shampooing your hair once or twice a day is important as most men use hair products on a daily basses. By starting fresh you are giving your hair and scalp the best protection.