Being overweight or obese is not only a matter of vanity, but most a health issue. Obesity is a medical condition that affects patients’ quality of life and may lead to numerous other associated comorbidities, such as insulin resistance, type 2 diabetes, hypertension, dyslipidemia, cardiovascular disease, stroke, sleep apnea, gallbladder disease, hyperuricemia, gout, osteoarthritis, and even cancer. Physicians diagnose obesity based on medical examination, including calculating patients’ body mass index (BMI).

Measurement and Classification of Body Mass Index (BMI)

BMI is a measurement calculated using someone’s weight divided by the square of its height. It can be calculated manually, but there are online calculators provided by the Centers for Disease Control and Prevention (CDC) and the National Institutes of Health (NIH). Having a high BMI can indicate high levels of body fat, which can be used by patients to keep track of their health and by physicians to screen weight problems.

After being calculated, the BMI is used to place patients into a category and evaluate their probability of developing health problems. Patients with a BMI lower than 18.5 are considered underweight, while levels between 18.5 and 24.9 are normal. However, patients with a BMI between 25.0 and 29.9 are classified as overweight, with BMI between 30.0 and 34.9 as class I obese, with BMI from 35.0 and 39.9 as class II obese, and with a BMI higher than 40.0 as class III obese.

Body Mass Index (BMI) Tendencies in the USA

According to CDC data, the prevalence of adult BMI equal or higher than 30 has greatly increased in the country since the 1970s. However, the same research demonstrates a stabilization of the trend, except for older women, since obesity continues to grow among women who are older than 60 years. For children and teenagers, the BMI is calculated differently, taking into consideration its expression in a growing percentile, which represents a child’s BMI relative to children in the U.S. who participated in national surveys that were conducted from 1963-65 to 1988-94.

“Because weight and height change during growth and development, as does their relation to body fatness, a child’s BMI must be interpreted relative to other children of the same sex and age. Normal or healthy weight weight status is based on BMI between the 5th and 85th percentile on the CDC growth chart,” explain the CDC. “The prevalence of children and teens who measure in the 95th percentile or greater on the CDC growth charts has greatly increased over the past 40 years. Recently, however, this trend has leveled off and has even declined in certain age groups.”

How to Lower Body Mass Index (BMI)

Having or adopting a healthy lifestyle is the first step to maintain or achieve a BMI classified as normal. Patients whose BMI is categorized as overweight may see improvements by dieting and conducting regular physical activity. However, for obese patients, it may be more difficult to lose weight alone. Therefore, there are numerous medically supervised weight loss programs that can help in the process. These include behavior modifications, pre-packaged meal replacement plans, pharmacotherapy, and surgical weight loss.

There are physicians specialized in weight loss, while patients can also access information from the CDC or NIH, including guides for behavioral changes and other materials. Losing weight may also improve patients’ quality of life and decrease the risk of developing potentially fatal conditions. Measuring waist circumference can also help screen for possible health risks that come with overweight and obesity, since having most fat accumulated around the waist rather than hips is an indicator of higher risk for heart disease and type 2 diabetes.

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