Firstly avoid alcohol in flight, with the pressurized air in the cabin your body dehydrates substantially, and alcohol affects the body clock by not giving you a full and refreshing sleep. In fact, try to drink as much water as possible. Just ask the steward for a large bottle and keep it by your seat so you can take sips whenever you want.

Drinking a lot of water will also help in other ways. It is highly recommended to move around when in-flight, walk up and down the plane, do some stretching exercises, to keep the blood circulating and stop the joints from stiffening. Whilst seated, swirl your ankles around from time to time.

Again, depending on whether you are travelling east or west, and how much sleep you require, you should set your watch to the local time of your destination as you board, and sleep according to that. This helps your body to start the change in its body clock, which is so important when combating jet lag. Let's say for example that you are flying from Delhi to Paris, then when you board the plane you should set your clock to Paris time and try not to sleep until it is close to sleeping time in Paris.

When you do arrive at your destination, and it is daytime, try not to go to sleep no matter how tired you are. Instead, try to go outdoors and into the sunshine if possible, this helps to alter your body clock and you will be back to normal a lot quicker. If you can't resist and your eyelids are drooping and you feel more and more tired, then set your alarm for four hours time, have a very hot bath and then jump into bed.