Physical development and growth are influenced by both genetic and environmental factors. For example, malnutrition can delay a child's physical development significantly. On the other hand, according to the University of Minnesota, the role of some environmental factors, such as the amount of exercise the child is getting, has a much smaller effect on physical development than was previously thought.
When a child is born, he has a unique set of genetic instructions that influence his physical growth. According to the University of Minnesota, genetics have a strong effect on rate of growth, the size of body parts and the onset of growth events. In one study, Dr. Stefan A. Czerwinski and colleagues followed their subjects for thirty years. By using such parental measurements as height and weight, these scientists were able to predict quite accurately the approximate height and weight of their subjects at the age of thirty. Other factors found to be closely linked to their parental values were blood pressure and body fat percentage, as well as muscle and total body mass. The study was published in the "American Journal of Human Biology" in September 2007.
Genetics alone, however, cannot determine the physical development of the child. The Minnesota Twin Studies have shown, for example, even identical twins who share the same genes can grow up to be of different height if they are raised in different environments. Such environmental factors as nutrition can affect physical growth significantly. According to the United Nations University, malnutrition can delay physical growth and development. It can also affect the quality and texture of bones and teeth, the size of body parts and delay the adolescent growth spurt. If the child gets better nutrition later on, she may be able to catch up, depending on how severe the malnutrition was. Besides diet, other environmental factors such as climate and toxins can also affect physical development.
Serious, chronic illness and surgeries have been shown to have a negative effect on a child's physical development. Dr. M. L. Cepeda and colleagues, for example, studied 30 subjects with homozygous sickle cell disease from age eight through 19. In their study, published in the "Journal of the National Medical Association" in January 2000, the authors reported that their subjects were significantly shorter and of lower weight than their healthy controls. The sexual development was also delayed in adolescents with sickle cell disease.
- "American Journal of Human Biology"; Genetic Factors in Physical Growth and Development and Their Relationship to Subsequent Health Outcomes; S A. Czerwinski et al.; September 2007
- United Nations University: The Effect of Malnutrition on Human Development
- "Journal of National Medical Association"; Physical Growth, Sexual Maturation, Body Image and Sickle Cell Disease; M. L. Cepeda, F. H. Allen, N. J. Cepeda, Y. M. Yang; January 2000