Defining A Calorie
![](https://img.lb.wbmdstatic.com/vim/live/webmd/consumer_assets/site_images/dam/editorial/healthy-living/diet-and-nutrition/nestle-what-is-calorie/graphics/thumbnails/final/nestle-what-is-calorie-280x190.jpg?resize=750px:*&output-quality=35)
Hide Video Transcript
Video Transcript
Narrator
What is a calorie? Marion Nestle, PhD, MPH
A calorie is a measure of energy. It's an amount of heat that you can measure and um, you can burn food in a machine that tells you how much heat it creates. It works exactly the same way in the body. And most people need between 2000 and 3000 calories a day. And an Oreo cookie has 50 calories, you eat two of them, that's a 100. You eat 10 of them that's going to be 500 and a quarter of your calories for the day. So you have to get a feel for it.