Waistlines Are Expanding In American Adults!

Body mass index (BMI), which is the ratio of weight in kilos to the square of height in meters, has usually been used in studies on obesity. In reality, BMI might not be an accurate measurement of abdominal obesity, which is defined as a waist circumference greater than 40.2 inches in men and greater than 34.6 inches in women.

People with abdominal obesity tend to have fat settled around their waistlines. Belly fat not only makes these people look apple-shaped but also put them at a higher risk of getting heart disease, diabetes, high cholesterol, high blood pressure, stroke and other obesity-related diseases. Hence, some researchers argued that waist circumference should be a better measure of abdominal obesity.

A recent study published September 17, 2014 in ‘Journal of the American Medical Association’ warned that American adult waistlines are still expanding despite stabilized BMI. Researchers at the Center for Disease and Control (CDC) found that the bellies have increased an inch to almost 39 inches over the last decade.

The researchers assessed weight of 32,816 people older than 20 (average age was 45) from 1999 until 2011-2012, using National Health and Nutrition Examination Survey (NHANES) data. Based on their waist circumference, 54 percent of Americans were abdominally obese in 2012, up from 46 percent 13 years earlier.

Waist circumference was found to rise from 37.6 inches in 1999-2000 to 38.8 inches in 2011-2012. Overall women’s waists increased by 1.5 inches to an average of 37.8 inches while men’s waist increased by about 0.8 inch. African-American waists increased by 1.6 inches to 39 inches, while Mexican-Americans saw an increase of 1.8 inches to 39.6 inches. 

It is not clear why waistlines are still increasing but BMI has not changed much. CDC researchers cited sleep deprivation, certain medications and lack of exercise as possible causes. The increase might also be related to pesticides, the plastics additive BPA and other chemicals that mimic hormones that can affect weight.

Ageing population might also contribute to the trend, according to experts not involved in the study. As baby boomers age, the natural decrease in muscle mass and slower metabolism can create more body fat. Given the size of the baby boomer generation, these aging changes will certainly impact statistics.

While all the reasons cited are purely speculative and unproven, it seems that reducing waistline is inevitable. Weight loss is probably the main strategy to cut the waist size. People are advised to have at least 5 or 6 hours of sleep nightly and to have at least 150 minutes of physical activity a week to help prevent weight gain.