Although more research is needed to fully understand the relationship between nutrition during gestation and birth weight to the onset of obesity later in life, several studies suggest a connection.
Studies show that 80 percent of children born to two obese parents become obese. Contrast that with the fact that only 14 percent of children born to normal-weight parents become obese. Studies on adopted children show that genetics account for only about 33 percent of a child’s weight. Family activity levels and eating habits are more important. Heredity controls only your metabolism.
Children’s health specialist William Dietz, Jr., MD, PhD, has determined that three critical periods may exist for the development of obesity: the prenatal period, childhood between the ages of 5 and 7, and adolescence.
The prenatal period: Research shows that a greater prevalence of adult obesity exists in babies born to diabetic mothers who tend to gain an above-average amount of weight during pregnancy and have large babies. Another study suggests that babies who are undernourished during the first two trimesters in utero have an increased risk of obesity as they age.
Between ages 5 and 7: In normal development during the first year of life, an infant’s body weight — specifically the amount of fat (adipose tissue) — is higher in proportion to the baby’s height. Gradually, the weight-to-height ratio declines. Then, between the ages of 5 and 7, children naturally increase their fat stores.
Nutritionists call this stage adiposity rebound. Some longitudinal studies suggest that children whose adiposity rebound occurs earlier (before the age of 5 1/2) are heavier and fatter adolescents and adults than children whose rebound is average (age 6 to 6 1/2) or even later. The hypothesis is that children who rebound earlier grow fatter for a longer period of time.
Adolescence: Other studies show that 80 percent of children who are obese during adolescence (ages 10 to 13) remain obese as adults. Girls have a greater risk than boys for getting and staying overweight; in fact, several studies show that 30 percent of all obese adult women were obese in early adolescence.