BMI Chart
A more visual way to find our BMI would be to use a BMI chart, here is an example:
The definition of body mass index (BMI) is the measurement of a person’s weight in relation to their height. Based on this measurement, a person’s weight will be categorised as either underweight, within the healthy BMI range, overweight, or obese, as defined by the World Health Organization (WHO).
BMI however cannot tell the difference between fat, muscle and bone density. For example, if you have low body fat and a lot of muscle, you may be classed as overweight or obese.
In 1985 the National Institutes of Health (NIH) recommended that physicians adopt the BMI as an index of obesity. It has now become the standard formula for assessing a person's risk of developing weight-related diseases, such as heart disease, high blood pressure, and diabetes.
Submit your height and weight to calculate your BMI
The Body Mass Index indicates an ideal BMI for most adults. The BMI ranges are:
Underweight = BMI <18.5
Healthy BMI weight = BMI 18.5–24.9
Overweight = BMI 25–29.9
Obesity = BMI of 30 or above
A more visual way to find our BMI would be to use a BMI chart, here is an example:
BMI is calculated using a straightforward formula:
BMI = weight in kg DIVIDED BY (height in m x height in m)
For example, if you weigh 70 kg and are 1.75 meters tall, your BMI would be:
BMI = 70 DIVIDED BY(1.75 x 1.75) = 22.9
You can also use the BMI calculator to find our which rage you're in, rather than working it out yourself, but this is how you calculate it manually.
While BMI is a useful general indicator of healthy body weight, it has limitations. It does not differentiate between muscle and fat, meaning individuals with high muscle mass (like athletes) may have a high BMI but not excess body fat. Similarly, people with a "normal" BMI could still carry unhealthy levels of visceral fat, particularly around the abdomen, increasing their risk for type 2 diabetes and other metabolic diseases.
To get a more accurate picture of health, waist circumference and the Body Roundness Index (BRI) can be valuable. BRI, which takes into account body shape and fat distribution, can provide a better assessment of health risks linked to obesity, especially for visceral fat. We know that fat stored around the abdomen (belly) is linked to a higher risk of type 2 diabetes and other health conditions in comparison to fat held around the hip area (apple shapes vs. pear shapes - which is largely determined by genetics).
BMI has limitations. It may not be an accurate tool for assessing weight status at an individual level as it does not consider a person’s fitness and muscle mass, ethnic origin, age, sex and body fat distribution.
It’s possible to have a ‘normal’ BMI and still be unhealthy. Similarly, it’s also possible to have a high BMI and be healthy. For example:
Athletes and bodybuilders who have a high proportion of muscle (muscle weighs more than fat) are categorised with a high BMI even though they may be a healthy weight.
There are height and weight ratio differences between races. For example, some ethnic groups may have a higher risk of certain health problems, such as diabetes, even if their weight is within a healthy BMI range for their height.
Due to loss of muscle mass, older people tend to have more body fat than younger people with the same BMI.
BMI cannot be accurately used for children and teenagers who are still growing and are not yet physically mature.
BMI for women can also be inaccurate as it does not account for pregnant or lactating women.
BMI for men and women may not always give an accurate presentation of health as women tend to have more body fat than men of an equal BMI.
At a population level, these limitations are not seen as particularly important as they even out across large numbers of people.
BMI for children is a measure used to assess whether a child has a healthy weight relative to their height, age and gender. Unlike adult BMI, which uses fixed categories (underweight, normal weight, overweight, obsese), BMI for children is assessed by using percentile ranges based on age and sex. This is due to children are still growing until the age of 18, a childrens body compositions change as they grow.
BMI = Weight (KG) divided by Height (m2)
After calculating a childs BMI, it is compared with percentile charts provided by health organizations.
BMI is a proxy measure of excess body fat.
Doctors use the Body Mass Index as a screening tool to identify a person’s weight category. For example, a person with a high BMI indicates they may have high body fat levels, which could lead to an increased risk of developing obesity-related illnesses, such as heart disease and type II diabetes. However, if a person has a very low BMI, this could indicate they have too little body fat, which can lead to other health problems such as anaemia, lowered immunity, and decreased bone density.
As BMI is a screening tool only - doctors would need to carry out further tests, such as a skinfold thickness check, waist measurements, diet and physical activity evaluations, and family history to accurately assess an individual’s overall health as BMI cannot alone be used as a diagnostic tool.
A BMI check is, therefore, most commonly used for monitoring the prevalence of overweight and obesity at a population level rather than an individual level.
While BMI is a useful general indicator of healthy body weight, it has limitations. It does not differentiate between muscle and fat, meaning individuals with high muscle mass (like athletes) may have a high BMI but not excess body fat. Similarly, people with a "normal" BMI could still carry unhealthy levels of visceral fat, particularly around the abdomen, increasing their risk for type 2 diabetes and other metabolic diseases.
To get a more accurate picture of health, waist circumference and the Body Roundness Index (BRI) can be valuable. BRI, which takes into account body shape and fat distribution, can provide a better assessment of health risks linked to obesity, especially for visceral fat. We know that fat stored around the abdomen (belly) is linked to a higher risk of type 2 diabetes and other health conditions in comparison to fat held around the hip area (apple shapes vs. pear shapes - which is largely determined by genetics).
If you are concerned about your BMI or need advice on any weight related health concerns, contact us today and a member of our weight loss team will discuss your concerns and options further with you.
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A normal BMI (Body Mass Index) typically falls between 18.5 and 24.9. This range is considered healthy for most adults as it indicates a balance between height and weight that is associated with a lower risk of health issues such as cardiovascular disease, diabetes, and certain cancers. However, BMI doesn’t account for body composition, such as muscle mass or fat distribution, so it is just one tool used in assessing health.
BMI is calculated using a straightforward formula:
BMI = weight in kg DIVIDED BY (height in m x height in m)
For example, if you weigh 70 kg and are 1.75 meters tall, your BMI would be:
BMI = 70 DIVIDED BY(1.75 x 1.75) = 22.9
There are many online calculators available, but this is how you can calculate it manually.
For adults, the standard BMI ranges (underweight, normal, overweight, and obese) apply across all ages from 18-65. However, in older adults, maintaining a BMI towards the higher end of the "normal" range or even slightly into the "overweight" category may be more beneficial for health and longevity. In children and adolescents, BMI is interpreted differently using age- and sex-specific growth charts.
As we age, our muscle mass typically decreases (known as sarcopenia), and fat distribution changes, so factors like waist circumference and the new Body Roundness Index (BRI) are useful in assessing health risks more accurately than BMI alone.
You can estimate your ideal weight range by using your height and targeting a BMI within the "normal" range of 18.5 to 24.9.
For example, if you are 1.70 meters tall, the weight range for a BMI of 18.5 to 24.9 would be:
Therefore, for someone who is 1.70 meters tall, a healthy weight range would be between 53.5 and 72 kg. Keep in mind, individual health is more nuanced, and factors like muscle mass, waist circumference, and lifestyle (including smoking status and alcohol intake) matter too.
While BMI is a useful general indicator of healthy body weight, it has limitations. It does not differentiate between muscle and fat, meaning individuals with high muscle mass (like athletes) may have a high BMI but not excess body fat. Similarly, people with a "normal" BMI could still carry unhealthy levels of visceral fat, particularly around the abdomen, increasing their risk for type 2 diabetes and other metabolic diseases.
To get a more accurate picture of health, waist circumference and the Body Roundness Index (BRI) can be valuable. BRI, which takes into account body shape and fat distribution, can provide a better assessment of health risks linked to obesity, especially for visceral fat. We know that fat stored around the abdomen (belly) is linked to a higher risk of type 2 diabetes and other health conditions in comparison to fat held around the hip area (apple shapes vs. pear shapes - which is largely determined by genetics).
Reducing BMI typically involves making sustainable lifestyle changes that promote fat loss. This includes:
If your BMI is elevated, it's important to focus on overall health improvements rather than the number on the scale alone. A reduction in waist circumference and body fat percentage may be more meaningful markers of health progress.
It’s possible to have a higher body weight without excess body fat. Muscle tissue weighs more than fat (it’s denser per volume), so individuals with a higher muscle mass, such as athletes or those who lift weights regularly, may weigh more but still have a low body fat percentage. BMI doesn’t account for this, which is why other measurements like body composition analysis or waist circumference are important.
Yes, BMI can easily be calculated at home using your weight and height. All you need is a set of (calibrated) scales, a tape measure, and access to the BMI formula. There are also numerous BMI calculators available online.
BMI is still widely used in clinical settings because it's a simple, quick, and cost-effective screening tool. However, it is increasingly seen as an incomplete measure of health. Waist circumference and new measures like the Body Roundness Index (BRI) offer more comprehensive insights, especially in assessing fat distribution and associated health risks. BRI, for instance, uses body shape to estimate fat distribution more effectively, which is important because excess abdominal fat is linked to higher risks of conditions like heart disease and diabetes.
In conclusion, while BMI is helpful, it’s important to look beyond it to get a fuller picture of health.
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