Why are they a dietary necessity?

What is USDA food pyramid? Are eating bread in a meal can ruin your diet? Is groundnut good for dieting? What does a normal healthy 10-year-old weigh? What do foods of plant origin contain? What are the ingredients in garnier nutrisse? Is it unhealthy to lose 20 pounds in one month if you weight 175 pounds? What is a Macro IV Tubing? How many soft drinks with Equal sweetener in it would you have to drink to have a health risk? Which of the following should you not do when eating fast food? If Joe would lose 2 pounds a week his intake is 4200 kcal a day and his energy expenditure does not change how many kilo calories should he consume each day to achieve his goal? How many calories should a 46 year old man eat per day? Does famous Dave's use msg? Am I fat if I weigh 200 and my height is 6'0? What is the flash point in fat? How much weight can a teenager lose by walking every day? What happens when the body uses more energy than the calories it takes in will produce? What fruit should diabetics eat? The total weight of all of the insects in the world is about 720 of a billion tons the total weight of humans is about 13 of this amountfind the total weight of all the humans? If a woman is 5'7 and wears a size 12 what does she weigh?