NSES Content Standard F  
Science in Personal and Social Perspectives: Personal health 
Grades K-4, page 140 

Nutrition is essential to health. Students should understand how the body uses food and how various foods contribute to health. Recommendations for good nutrition include eating a variety of foods, eating less sugar, and eating less fat. 

Benchmark 6E The Human Organism: Physical Health
Grades K-2, page 144
Eating a variety of healthful foods and getting enough exercise and rest help people to stay healthy.

Benchmark 6E The Human Organism: Physical Health
Grades 3-5, page 144
Food provides energy and materials for growth and repair of body parts. Vitamins and minerals, present in small amounts in foods, are essential to keep everything working well. As people grow up, the amounts and kinds of food and exercise needed by the body may change.

Science for All Americans The Human Organism
Chapter 6, page 82
The fact that most people now live in physical and social settings that are very different from those to which human physiology was adapted long ago is a factor in determining the health of the population in general. One modern "abnormality" in industrialized countries is diet, which once included chiefly raw plant and animal materials but now includes excess amounts of refined sugar, saturated fat, and salt, as well as caffeine, alcohol, nicotine, and other drugs.