High metabolism

Im a 19 year old male and have a high metabolism but not much of an appitite for food, im average build I weigh about 11 stone, the problem I have is nomatter what I eat I can never seem to put on weight but the strange thing is I never seem to lose weight either.
Can anybody give me any advice about how to put on weight or does anybody know a way of slowing down your metabolism without drugs or special trament??

Forget the pills to slow your metabolism. As you age, your metabolism will most likely slow down naturally. Instead, follow these tips to help you gain weight in a healthy manner.

1) Choose healthy high calorie foods such as: Nuts, nut butters, avocados, regular oil based salad dressings, vegetable oils, and olives. These foods all contain heart healthy mono and polyunsaturated fats.
- Try snacking on a handful of nuts or olives in between meals. Add nuts to salads, cereal, shakes, etc.
- Have peanut butter sandwiches; add peanut butter to shakes, oatmeal, or on fruit.
- Dip veggies into oil based salad dressings.
- cook with vegetable oils.
- Try avocado slices on sandwiches.

2) Eat frequently. Aim for about 3 meals + 3 snacks per day. If it's tough for you to eat this frequently try shakes (such as protein shakes, yogurt shakes, etc). For many people it's easier to drink their calories than to eat them.

3) Choose low fat dairy and lean meats most of the time. Dairy and meat products are a source of saturated fat, the type of fat associated with increasing the risk of heart disease. Although you're looking to gain, lean meats and low fat dairy products are still a better option (low fat NOT non-fat).

4) Choose meals and snacks that contain a mix of nutrients (carbohydrate, protein and fat) For example: a sandwich on whole wheat bread with turkey, low fat cheese, avocado slices and some lettuce and tomato.

5) When exercising, focus more on strength training which helps build muscle and mass than cardiovascular exercise which predominantly burns fat.

6) Choose regular beverages. Soft drinks are not the most nutritious option for weight gain, but they can contribute a lot of calories to your total daily intake. 100% juice is a better option than sodas or other soft drinks such as fruit punch or ice tea.

Muscle weighs more than fat, so lift wights eat lots of protein, eggs and nut's area good source. Stay away from sugar and caffeine. Lot's of starch and carbs as well, potato's and breads are good for these. Dairy foods are a healthy source of fat which you will also burn by lifting weights. If I'm correct you not trying to gain fat just more weight so you don't seem so skinny. To do that you need to build fat and turn it into muscle.