How long can I go without eating?!

Anywhere from 5 days to 2 weeks depending on certain factors such as
Initial state of health. Those who are physically healthy and have been consuming plenty of good nutritious food have an advantage. During the start of a food shortage their systems are fully stocked to begin with. During food shortages your body can draw from this supply of nutrients and extend the length of time you can live without eating.
Amount of muscle on the body. Muscle is broken down by a starving body and used for both fuel and nutrients. On the other hand, even at rest lean muscle burns calories.
Amount of body fat. Each pound of body fat contains about 3600 calories, enough energy for the average person for about a day and half. During a survival situation when there is not enough food to eat, a few extra pounds can come in handy. Indeed, gaining weight when food is plentiful is an important survival mechanism.
Your metabolism will be a factor in determining how long you can live without food. Individual metabolisms vary. As you go without food your metabolism will naturally slow, but those people who are already starting from a lower baseline will have an advantage in using less calories and therefore living longer.
The amount of work we are performing while going without food. Being active requires increased amounts of calories and nutrients. If you are forced to live without food, the less active you can remain the longer you will last.
The temperature of your environment has a direct bearing on how long you can live without food. Below a comfortable temperature your body will be expending additional calories as it attempts to stay warm. In hot environments your body will expend additional calories in trying to say cool, and your body will be loosing precious electrolytes via your sweat. When stressed by lack of food you are more susceptible to heat exhaustion and heat stroke.
If you can stay adequately hydrated you can live without food for a longer period of time than if there were shortages of food and water together.

http://www.survivaltopics.com/survival/how-long-can-you-live-without-food/

Humans can go a long time without eating (weeks) but only a few days without water. If you don't eat, your metabolism slows down and you'll gain weight back when you start eating again.

well if you drink water you can go for 40 days or so even though some indian moncks claim to have gone 3 years. BUt without water you can only live for about 7 days

My son the popular belief is as follows..

3 minutes without air
3 days without water
3 weeks without food

Don't be silly.