The scale doesn’t have all the answers. It can tell you how much you weigh, but it can’t assess your weight and health risk, which can indicate if you’re at risk for developing heart disease, high blood pressure, type 2 diabetes, gallstones, breathing problems and certain cancers, states the U.S. Department of Health and Human Services. To assess those risk factors, doctors suggest measuring how much body fat you have using the Body Mass Index (BMI).
Body Mass Index
The BMI can give you general insight into your overall health, according to the National Heart Lung and Blood Institute, and uses your height and weight to measure your body fat. For example, a woman who is 5 feet 3 inches tall and weighs 130 pounds will have a BMI of 23.0, which is safely in the normal weight zone. If you score under 18.5, you’re considered underweight. If you're between 25 and 29.9, you’re considered overweight. Anything higher is a sign of obesity. But your height and weight can’t tell the whole story, which is why some doctors take other measurements to get a better idea of your overall health.
The National Heart Lung and Blood Institute recommends measuring your waist circumference to screen for obesity-related health risks. Women with waists that measure 35 inches or more, and men with waists that measure 40 inches or more are at risk for developing type 2 diabetes and heart disease. To measure, wrap a tape measure around your waist, just above your hipbones. Take your measurements after an exhalation.
Measuring your waist-to-hip ratio (WHR) is another way to determine your risk for developing weight-related diseases, reports the National Heart Lung and Blood Institute, and the formula is as easy as the one used for measuring your BMI. Measure your waist right above your hipbones, then measure the widest part of your hips. Dividing your waist measurement by your hip measurement will give you your WHR ratio. For example, a woman with an 20-inch waist and 24-inch hips will have a WHR of 0.83. Anything higher than 0.8 means you’re at higher risk for developing a weight-related chronic condition.
Arm and Leg Measurements
According to a study published in a 2003 issue of the journal “Clinical Nutrition,” a close relationship exists between arm circumference and your BMI. The thinner your arms, the more likely it is that you are suffering from a nutrition deficiency and likely have low BMI. A 2000 study published in the “International Journal of Epidemiology” found the same to be true of the relationship between leg circumference and BMI. Study authors suggest taking measurements other than BMI to measure a person’s risk for developing a weight-related disease, especially when weight and height are self-reported.
- International Journal of Epidemiology: How accurately are height, weight and leg length reported by the elderly, and how closely are they related to measurements recorded in childhood?
- Clinical Nutrition: A Comparison of Mid Upper Arm Circumference, Body Mass Index and Weight Loss as Indices of Undernutrition in Acutely Hospitalized Patients
- Centers for Disease Control and Prevention: About BMI for Adults
- National Heart Lung and Blood Institute: Calculate Your Body Mass Index
- National Heart Lung and Blood Institute: Assessing Your Weight and Health Risk
- Emergency Nutrition Network: Assessing Nutritional Status Using Arm Span Measurement
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