The most common way to quantify obesity is to use the body mass index (BMI), which relates body weight to height by using the following formula: BMI (kg/m2) = weight (kg) / height2 (m) What are the BMI levels? Depending on the outcome of the BMI calculation, body weight and obesity in adults ( except pregnant women) can be classified in accordance with the following levels: BMI - less than or equal to 18.5 kg/m 2 Low body weight BMI - 18.5 to 24.9 kg/m 2 Normal body weight BMI - 25 to 29.9 kg/m 2 Excessive body weight BMI - 30 to 34.9 kg/m 2 Moderate obesity BMI - 35 to 39.9 kg/m 2 Morbid obesity BMI - equal to or greater than 50 kg/m 2 Severe obesity Excessive body weight vs obesity A person is considered to have excessive body weight when they weigh up to 20% more than the “normal” range (BMI of between 25 kg/m2 and 29.9 kg/m2). The term obesity is applied to situations where body weight exceeds “normal” by more than 20% (BMI greater than 30 kg/m2). Usually, an excess of weight resulting in a higher than normal BMI is related to excess body fat . Is BMI a direct measurement of body fat? BMI is not a direct measurement of body fat as it does not take into consideration the proportion of body weight it represents. For example, some individuals with significant muscle development (such as athletes) have a higher than normal BMI yet do not have excess fat on their bodies. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
