Maintaining a healthy diet is very essential in getting rid of excess oil in your hair.
• It is very important for you to drink plenty of water to keep your body hydrated at all times.
• Make sure that you avoid consuming a lot of oily or greasy foods.
• Add healthy fats like olive oil, nuts and fish in your diet.
• It is important to eat a lot of fruits and vegetables to keep your scalp healthy.
Source: http://www.healwithfood.org/greasyhair/diet.php#ixzz3qcUHpDjV