Improved Nutrition and Human Growth

Improved nutrition and human growth are closely linked. Nutritional factors affect fetal development, adolescent sexual development, and adult height and weight. Human growth rates and levels vary worldwide and throughout history, based in part on the nutrition provided by each culture's available food sources.

Types

• Several types of human growth are related to nutritional factors. These include infant development, brain and neural system development, average height on reaching adulthood, the age of reaching sexual maturity, and growth in excessive bulk or obesity.

History

• Although human height is tied to nutrition as well as genetic factors, height has not increased steadily throughout history. Human height has varied around the world and is dependent on food nutrition, as well as economic factors including how much effort must be expended to obtain food, cultural factors such as how much time is spent stressed or engaged physical activity, and environmental factors such as the severity of winters. Economic historian Richard Steckel of the University of Ohio reports that in the 1800s, the Cheyenne Indians were likely the tallest people in the world with an average male adult height of 5 feet, 10 inches tall--the same as average American males today. Steckel also says that Northern Europeans were on average almost three inches taller in the 11th century than in the early 18th century.

Misconceptions

• Height and weight are good indicators of nutrition in infants and children. However, bigger is not necessarily always better. According to World Health Organization infant and children growth charts, breast-fed children are, on average, smaller than artificial formula-fed infants and children. However, breastfeeding is nutritionally superior to formula and provides numerous additional health benefits. Breastfeeding contributes less to growth of height and weight, but more to growth of neurological systems. Growth is not always good in adults, either: Americans' average height has plateaued, but they are now growing out instead of up. America leads the world in obesity rates, with over 30 percent of the adult population clinically obese, according to data from the Organisation for Economic Co-operation and Development.

Significance

• The relationship between nutrition and human growth is particularly significant in infancy and early childhood. According to Facts for Life--a publication of the United Nations Children's Fund, the World Health Organization, the United Nations Educational Scientific and Cultural Organization and others--breastfeeding alone provides sufficient nutrition for infants until age six months. Facts for Life reports that regular weight gain from adequate nutrition "is the most important sign that a child is growing and developing well." Malnutrition weakens the body's immunity to illness, and more than half of all child deaths worldwide are associated with malnutrition.

Considerations

• Improper nutrition, rather than simple malnutrition, can lead to serious health concerns. Early onset of puberty in girls is linked to significantly increased risk of breast cancer. Researchers at the Harvard School of Medicine report that increased ingestion of animal fats and decreased intake of vegetables in female childhood leads to more rapid growth of sexual development, including earlier onset of menstruation.

Time Frame

• According to Facts for Life, the relationship between nutrition and human growth starts before conception. Proper maternal nutrition before and through pregnancy aids in proper, healthy fetal growth. This relationship continues to a person's last years of life. Elders tend to lose height due to osteoporosis, a condition of bone density loss linked in part to insufficient consumption of vitamin D and calcium. Elders often also lose dangerous amounts of weight, because diminished appetite or difficulties in chewing or digesting lead to inadequate nutrition.