Body mass index (BMI) is an estimation of body fat based on height and weight. According to the National Heart, Lung and Blood Institute (NIH), a BMI of 26 falls into the overweight range of 25 to 29. Measurements between 18.5 to 24.9 indicate normal weight, while measurements above 30 indicate obesity. The institute above categorizes BMIs of less than 18.5 as underweight.
A BMI of 26 means a person is overweight.
Factors That Affect BMI
Since BMI measurements are simple and inexpensive, doctors use them as a screening tool for obesity, but they aren't diagnostic, reports the Centers for Disease Control and Prevention (CDC). The relationship between BMI and body fat may vary with gender, age and ethnicity. At the same BMI, men have less body fat than women, and older people have less body fat than younger adults, says the CDC. The CDC also notes that in general, black people have less body fat than white people of the same BMI; and Asian people have more body fat than white people of the same BMI.
While BMI is a reliable screener of body fat in most people, athletes with dense muscles have higher BMI scores, says the American Heart Association (AHA). For these people, waist circumference measurements may be a more reliable means of estimating body fat. However, because fat in the abdomen has implications for long-term health, measuring both BMI and waist circumference may be a better means of determining anyone's weight-related risk, states Harvard T.H. Chan School of Public Health.
BMI of 26 Health Effects
BMI categorizations are the same for men and women. Therefore, the healthiest scores for either sex would fall in the normal weight range of 18.5 to 24.9, notes the CDC. BMIs of 25 or higher mean the person is at greater risk of an array of adverse health effects.
The CDC provides a formidable list of health consequences of obesity. These include high blood pressure, cholesterol and triglycerides, as well as an increased risk of diabetes, stroke and coronary heart disease. The obese also have an elevated likelihood of osteoarthritis, gallbladder disease, mental illness, some cancers, chronic inflammation and body pain. Moreover, obesity is associated with a lower quality of life and raises the incidence of all-cause mortality.
Older adults may be exempt from some of the health effects associated with being overweight. In a 2014 study published in the _American Journal of Clinical Nutritio_n, researchers found a higher mortality rate wasn't tied to being overweight in people over the age of 65. Conversely, due to a tendency of this age group to suffer from undernutrition, the risk of death was higher in those with BMIs of less than 23.
Normal BMI Health Benefits
Furthermore, the benefits of a healthy BMI involve effects that are the opposite of those associated with having a BMI in the overweight and obese categories. These consist of a decreased burden on the heart and less pain, along with a reduced risk of diabetes and certain cancers, adds the AHA.
Recommendations for Unhealthy BMIs
People may get their BMI online at websites, such as the one at NIH, simply by putting their height and weight into the calculator. Doctors recommend a weight loss program in cases of a BMI of 30 and above. They also advocate weight loss for those who have a BMI ranging between 25 and 29.9, especially if they have two or more risk factors for heart disease like high blood pressure and physical inactivity.
- National Heart, Lung and Blood Institute: "Calculate Your Body Mass Index"
- American Heart Association: "Body Mass Index (BMI) in Adults"
- Centers for Disease Control and Prevention: "About Adult BMI"
- Harvard T.H. Chan School of Public Health: "Why Use BMI?"
- The American Journal of Clinical Nutrition: "BMI and All-Cause Mortality in Older Adults: A Meta-Analysis"
- National Heart, Lung and Blood Institute: "Assessing Your Weight and Health Risk"