The food guide pyramid was developed by the US government and used to resemble a triangle, with lists of the best foods. As the triangle moved toward the top, foods that were less healthy were listed, suggesting smaller recommended amounts. In 2005, the pyramid underwent changes that reflect a more individualized approach toward nutrition. It was changed again in 2011 from a pyramid to the image of a plate divided into different sections for each food group.
When someone visited the nutrition guide website for the US Department of Agriculture (USDA), he or she was asked a few questions before viewing the food guide pyramid. These questions included the person's age and level of activity per week. Answering these questions was designed to help calculate a model of the best types of foods depending on the answers.
Originally, the food guide pyramid had little pictures of food listed in horizontal rows. In 2005, this was changed to bars of color, which are shorter or wider depending upon a person’s dietary needs. Each user got specific information about what kind of foods should be eaten and appropriate quantities. Each bar of color represents a food group, but the actual written information is probably more helpful.
The pyramid also offered a feature that allowed the user to check his or her current weight as well as age and activity level. It gave specific recommendations on how much activity one should try for each day as well as total calorie intake, based on the best possible foods.
The changes in the food guide pyramid were prompted by the fact that individuals have different caloric needs. For example, a 25-year-old female who exercises 30-60 minutes a day is given a daily caloric intake of 2,200 calories. She should aim for eating 7 ounces (199 grams) of grains, 3 cups (about 400-500 grams) of vegetables, 2 cups (about 220-350 grams) of fruits, 3 cups (710 ml) of milk, and 6 ounces (170 g) of meat or beans.
The same aged female who exercises less than 30 minutes a day has results based on a 2,000-calorie diet. This particular woman should eat 6 ounces (170 g) of grains, 2.5 cups (about 330-415 grams) of vegetables, 2 cups (about 220-350 grams) of fruit, 3 cups (710 ml) of milk and 5.5 ounces (156 g) of meat or beans.
The guidelines may require adjustment if the person needs to lose weight, or if he or she has allergies to certain foods. In these cases, it may be best for the person to consult a nutrition expert about the best diet. For those without allergies, adhering to the food guide pyramid allows a person to maintain his or her weight. Naturally, increasing exercise in most cases, while eating less food, can help one lose weight.