Childhood Obesity

Childhood Obesity Can Start in the Womb

By: Kristen L. Miller, MS

We are facing in epidemic of childhood obesity here in the US.  Obesity in children has increased from 5% in the 1960’s to 17% currently (Ogden et al., 2006).  There are many factors that may contribute to childhood obesity, such as diet, sedentary lifestyle and role models, all postnatal issues.  However, growing research points to the prenatal environment as the one most closely associated with childhood obesity.

The Institute of Medicine has recommended weight gain guidelines for pregnant women based on pre-pregnancy BMI.  It appears that women who gain more than the recommended weight may predispose their kids to childhood obesity (Rasmussen K. and Yaktine, A, 2009).  This holds true regardless of pre-pregnancy weight classification.  Women who have normal pre-pregnancy BMI values are just as likely to have overweight children as women who are overweight or obese before conception.

The main culprit is thought to be blood sugar, which is often elevated in women who gain too much weight during pregnancy, whether or not they develop gestational diabetes.  Glucose passes through the placenta, but insulin does not, therefore, when fetal blood sugar is elevated the fetal pancreas must secrete more insulin to normalize blood sugar levels.  Insulin is a growth factor, thus, elevated fetal insulin causes the fetus to grow larger.  The elevated insulin may also lead to increased appetite and weight gain in childhood.

The most important steps a pregnant woman can take to avoid this dilemma are to optimize nutrition and exercise regularly during pregnancy.  The goal is to exercise at an intensity of at least 60% of heart rate reserve (Max HR- Resting HR) for at least 30:00 on most days of the week.  This may be contrary to what pregnant women were told just a few years ago.  Current research and the American College of Obstetricians and Gynecologists (ACOG) support these guidelines as well (Zavorsky and Longo, 2011a).

Great effort is being taken to change the nutrition and activity behaviors of children.  Parents, especially mothers, can help by optimizing maternal health through good nutrition and exercise.  Mothers have the power to shape the future of their child’s health before they are even born!

Ogden, C.L. et al. (2006). Prevalence of overweight and obesity in the United States, 1999−2004. Journal of the American Medical Association, 295, 13, 1549−1555.

Rasmussen K. and Yaktine, A. (2009). Weight Gain During Pregnancy: Reexamining the Guidelines. Washington, D.C.: Institute of Medicine

Zavorsky, G.S. and Longo, L.D. (2011a). Exercise guidelines in pregnancy: New perspectives. Sports Medicine, 41, 5, 345−360