The food pyramid, which is updated in the United States once every five years (the last update was in 2005) is basically a guide which tells you what your nutrition levels should be. The original food pyramid was first printed in 1992 to replace one of the oldest systems of food classification. Although the newer food pyramid is taking into account a lot more in terms of exactly what foods you should be eating it still has quite a bit of way to go till it is anyway perfect.
The unfortunate thing is that today we have more obesity in the Western world than ever before. People are eating rubbish food and not getting enough exercise. The food-pyramid is a basic synopsis of the daily intakes of all the different food types that you should be having. The new food pyramid also includes sections on the amount of exercise you should be taking.
For instance, the new food-pyramid tells you that you should have about 30 minutes a day of between moderate and vigorous exercise. It explains the difference between moderate exercise and vigorous exercise. One of the things that it promotes as moderate exercise is brisk walking, which it defines as walking at around 3 1/2 mph. One of the examples of vigorous physical exercise is walking very fast which it classifies as being over 4 1/2 miles per hour. You can also see food pyramids for children, food pyramids for vegetarians, even cultural food pyramids for different types of diet, for instance Chinese food pyramid.