Nutritional and energy needs for a child differs profoundly from that of an adult because of a child's continual growth and development. A child is in greater need of nutrient-dense foods--although not to the extent as infants--and requires more energy for basal metabolic rate, physical activity and thermic effect of food. Energy needs are highest during rapid growth and expansion of lean mass.
Each individual child is best understood by first dividing stages of child growth and development into two periods: a preschool period and a school-age period:
- During the pre-school period, from 2-6 years of age, the child grows more slowly in comparison to infancy. A toddler will quadruple birth weight in a full year or so. The brain of the toddler also grows more slowly than as was expected as an infant so head circumference will only increase by a couple of centimeters. A toddler's weight increase can range from 2.5 kg per year for ages 2 and 3 to 2 kg per year for ages 4 and 5. She or he will also grow about 12 cm from age 2 and 3. During that time, body composition will also change as total body water content settles to a comfortable 60-65% and growth of new cells and skeletal muscle causing a decrease in extracellular fluid and increase in intracellular fluid.
- The school-age period, or latent growth period, beigns from 6 until puberty of which girls can reach a little earlier at 10 and boys normally at 12. As "baby fat" is lost, the child becomes leaner and mor muscular. The pattern of growth is highly individual. On average, weight increase will be about 3-3.5 kg per year during this period. The child will move beyond the limited vocabulary of three-word-sentences and begin adapting to an environnment of greater language skills, motor skills, as well as personal-social skills. This, of course, will also mean more control over diet through self-feeding.
As both periods represent critical times for growth and development, the focus of recommendations for energy and nutrient intake are based on supporting optimal outcomes. The recommendations are, again, more critical than for adults because of dire long-term consequences. A child, for example, will need special attention to be sure that they receive proteins of high biologic value for growth requirements. Fat and carbohydrate needs will be greater during rapid growth periods as will numerous vitamins and minerals, especially vitamin D and calcium of which are largely deficient in children. Fiber too, which helps normalize bowel movements, is critical for ensuring a child lives free of future risk of disease. All in all the goal is to provide the best support to provide children with bright futures.
Mitchell MK. Nutrition Across the Life Span. "Chapter 9: Nutrition During Growth: Preschool through Preadolescence". Second Edition. Waveland Press: Long Grove, Illinois, 2003, pp. 271-300.