Dandruff is a common condition. It is estimated that half of all people will be affected by dandruff at some point in their lives. Dandruff often occurs after puberty and is most common in people in their early 20s, continuing into middle age. It has been reported that dandruff is more common in men than women. It is thought to affect all ethnic groups equally. The main treatment for dandruff is anti-dandruff shampoo. There are a number of different types available over the counter from most pharmacists and supermarkets.