Childhood Overweight & Obesity

The information on this page has been compiled and edited from previously published articles, by Dr. Connie Guttersen.  The articles are not intended as health advice, nor do they necessarily reflect the views and opinions of the California Olive Committee. Always consult your physician on matters of health and wellness.

by Connie Guttersen, RD PhD.

The prevalence of overweight among children and adolescents has been increasing at an alarming rate. In addition to the increased prevalence, the degree to which children and adolescents are overweight has also dramatically increased. Data from the National Longitudinal Survey of Youth indicates a marked increase in the severity of overweight among children 4 to 12 years of age in the past 20 years.

As the scientific literature takes a closer look at the impact of these figures, we find that childhood obesity is not just a cosmetic problem related to excess calories. This trend is closely related to an increase in type II diabetes, a concern for a shorter life span as an adult, and nutritional deficiencies which may affect immune function, memory, learning abilities, and behavioral/mood levels such as shorter attention span, irritability and aggressive behavior.

Iron and zinc are two examples of common nutrient deficiencies found in overweight and obese individuals.

Americans, including children, are eating more calories then ever, while not meeting the recommended dietary allowances for key nutrients such as folate, calcium, vitamins A, C, B6, zinc, and iron.  In other words, the everyday foods consumed are energy dense but not nutrient rich choices. Daily meals of snack foods, fast food, and processed foods do not supply adequate levels of critical nutrients for growing children. These concerns are even larger when it comes to the overweight and obese child. Overweight bodies have higher nutritional needs than normal weight bodies, compounding the problem for nutrient deficiencies and malnutrition. Iron and zinc deficiencies are two examples of common nutrient deficiencies found in overweight and obese individuals as compared to normal weight individuals.

Obesity related to increasing incidence of iron deficiency

Children and adolescents who are overweight are more likely to be iron deficient than normal weight children. A recent study, published in 2004 in Pediatrics found that although children tend to consume large amounts of calorie dense foods, they are not nutrient rich choices. In this study, 9,698 children were examined. Overall, the prevalence of iron deficiency increased as BMI increased from normal weight to at risk for overweight to overweight, ( 2.1%, 5.3%, and 5.5%, respectively).

In summary, the multivariate regression analysis concluded that children who were at risk for overweight and children who were overweight were approximately twice as likely to be iron deficient as those who were not overweight. The association between iron deficiency and overweight may have important public health and clinical implications. The screening may need to be modified to pay special attention to those individuals with higher BMIs.

Dietary Sources of Iron

The impact of these findings brings together the gap we must address behind the cosmetic, medical, and social aspects of obesity among children and adolescents. A deficiency in iron not only results in poor energy levels and decreased immune function; it can affect learning abilities, especially those related to memory, attention span, and math. Research shows that even mild, short term iron deficiency affects academic performance. A recent study found that 84% of children studied who had attention deficit hyperactivity disorder, ADHD, also had abnormal iron stores. In addition, they found the children with the lowest iron stores had the most severe ADHD symptoms. Some of the best food sources of iron are lean beef, pork, enriched whole grains, and beans.

Research shows that even mild, short term iron deficiency affects academic performance.

Nutrient rich choices in daily foods prevent borderline deficiencies of other common nutrients, which are a challenge for children. Another study, published 2004 in the American Journal of Psychiatry shows that children who experience certain nutritional deficiencies demonstrated a 41% increase in aggression at age 8. At age 17, they demonstrated a 51% increase in violent and antisocial behaviors. The study concluded that the difference in comparison to children who did not reflect these behavioral traits was related to the foods they were eating and the nutrients they were missing. The four primary nutrients missing were iron, zinc, B vitamins, and protein. They were not getting enough of these nutrients to develop healthy nervous systems. A healthy nervous system is important for mental and emotional health.


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