Ponderal Index at Birth is a Better Predictor of Future Obesity
A doctor determines if children are overweight by measuring their height and weight. Although children have fewer weight-related health problems than adults, overweight children are at high risk of becoming overweight adolescents and adults. Overweight adults are at risk for a number of health problems including heart disease, diabetes, high blood pressure stroke, and some forms of cancer.
Measurement of birth weight compared with length is a better predictor than birth weight of how fat a child will become, UK researchers report.
The measurement, known as the ponderal index, is calculated by dividing weight in kilograms by length in centimeters cubed. It is similar to the better-known body mass index (BMI, weight in kilograms divided by height in meters squared) but is thought to provide a better gauge of weight in relation to height and body composition.
Rohrer's ponderal index in newborns (birth weight/height3x100) has been used as an indicator of fetal growth status, especially to assess asymmetrical intrauterine growth retardation.The ponderal index is somewhat comparable to Body mass index, but gives a more fair comparison between individuals of different stature.
Study suggested that death from coronary heart disease was associated with low birth weight and, more strongly, with a low ponderal index at birth. Men who died from coronary heart disease had an above average body mass index at all ages from 7 to 15 years. In a simultaneous regression the hazard ratio for death from the disease increased by 14% (95% confidence interval 8% to 19%; P
- Men who had low birth weight or were thin at birth have high death rates from coronary heart disease
- Death rates are even higher if weight “catches up” in early childhood
- Death from coronary heart disease may be a consequence of prenatal undernutrition followed by improved postnatal nutrition
- Programmes to reduce obesity among boys may need to focus on those who had low birth weight or who were thin at birth
While birth weight has been linked with obesity risk in both children and adults, Dr. Imogen S. Rogers of the University of Bristol and colleagues note, information is lacking on how birth weight affects a person's percentage of fat and lean mass.
To investigate, the researchers used a technique called dual-energy X-ray absorptiometry to precisely measure lean body mass and body fat percentage in more than 6,000 boys and girls who were between 9 and 10 yeas old.
While both fat mass and lean mass rose with birth weight, there was no relationship between birth weight and the ratio of fat to lean mass, the researchers found. However, the higher a child's ponderal index at birth, the greater the ratio of fat to lean mass at age 9 or 10. Higher ponderal index was also associated with a higher percentage of body fat.
Children who were longer at birth had lower percentages of body fat as children, as well as less fat in relation to lean body mass.
Rogers and her team conclude that the well-established association between greater weight and birth and higher future BMI is due to increases in both fat and lean body mass.
They conclude that ponderal index at birth is a better predictor of future obesity than is birth weight.
In the United States, at least one child in five is overweight. The number of overweight children continues to grow. Over the last 2 decades, this number has increased by more than 50 percent, and the number of "extremely" overweight children has nearly doubled.Everyone should know that:
- Obese children and adolescents have shown an alarming increase in the incidence of type 2 diabetes, also known as adult-onset diabetes.
- Many obese children have high cholesterol and blood pressure levels, which are risk factors for heart disease.
- One of the most severe problems for obese children is sleep apnea (interrupted breathing while sleeping). In some cases this can lead to problems with learning and memory.
- Obese children have a high incidence of orthopedic problems, liver disease, and asthma.
- Overweight adolescents have a 70 percent chance of becoming overweight or obese adults.