BMI (body mass index) is a measurement that estimates the amount of body fat you have, based on your height and weight. It can be used by medical professionals (or yourself) to categorise you into the following weight groups:
Your BMI is calculated with the formula:
Weight (kg) divided by height (m)
The ideal BMI weight category would be a healthy weight, which is a BMI score of 18.5 up to 24.9.
For women, the ideal healthy BMI score is from 18.5 to 24.9. A BMI below 18.5 is considered underweight, and a score above 24.9 is considered overweight. The ideal BMI score for men is the same, but the measurement limits used to get the BMI scores vary for men and women.
Your BMI score indicates if you are at a healthy weight for your height. Depending on what your score is, it could mean different things. There are 5 different weight classes, each with different risks.
Being underweight means you may not be getting enough energy or nutrients to fuel your body. This can lead to fatigue and various health conditions, such as a weakened immune system and malnutrition.
Maintaining a healthy weight is important. Staying within the healthy weight range can vastly decrease your chances of serious health issues.
The overweight, obese and severe obesity categories indicate that you have too much body fat for your height. Overweight and obesity are linked to an increased risk of various health problems, including heart disease, type 2 diabetes, and certain cancers.
Generally, medical help is not a necessity if you haven’t already developed the health issues associated with being obese. Medical help can be beneficial for those who have adapted to a healthier lifestyle and whose weight/BMI is not shifting.
Medical help will also be necessary if health issues like diabetes or high blood pressure occur.
Medicines such as Wegovy (semaglutide), Mounjaro (tirzepatide), liraglutide and Orlistat can help manage obesity and diabetes.
In some instances, your BMI score can be slightly inaccurate. Some people who may have an inaccurate BMI score are:
Your weight in kg on a scale doesn’t account for muscle mass compared to body fat, and since muscle weighs more than fat (as it’s denser) your weight may seem heavy. Having very little body fat but a high BMI score is inaccurate.
BMI scores are primarily based on data from white European populations and don’t account for the differences in body composition or fat distribution among various ethnicities.
Your BMI score doesn’t account for weight gained during pregnancy (or the weight of the baby), nor does it consider the significant change in body composition. If you do decide to check your BMI score whilst pregnant, bear in mind that it will be inaccurate, and weight gain during pregnancy is natural and healthy.
While the formula for calculating a person’s BMI is the same for children, it needs to be age and sex specific. It also doesn’t take bone density into consideration.
BMI scores in people over 60 are inaccurate as they don’t take into consideration age-related changes in body composition, such as the decrease in muscle mass and increase in body fat.
Your waist circumference is the measurement of your waist (all the way around the body), and it’s used to gauge your abdominal fat levels. The hip-to-waist ratio also checks it. A bigger waist circumference usually means more abdominal fat and a higher risk of health issues such as heart disease, type 2 diabetes and high blood pressure.
The ideal waist circumference varies by gender and ethnicity.
For women, the ideal waist circumference is anything less than 35 inches.
For men, the ideal waist circumference is anything less than 37 inches.
A BMI class of overweight, obese or severely obese would indicate that a lifestyle change is needed, and if you need medical support, we can help!
If you are worried about your BMI score, you can start a consultation with us:
One of our prescribers will assess your information.
