Body mass index
Metabolic Health
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Determining Body Mass Index 

Did you know that each year, 4.7 million premature deaths are caused by obesity? One of the biggest health issues in the world today is obesity, which is no longer only a burden in advanced economies but affects people of all socioeconomic backgrounds. Children, men, and women are all equally and severely impacted. As a matter of fact, nutritional deficiencies and contagious diseases, which were previously major causes of public health challenges, aren't any longer the primary causes of worldwide ill health since being overweight, obesity, and the health issues they are connected with are now so widespread. Obesity is characterized physiologically as an irregular or abnormal buildup of fat in adipose tissue to the point that the health and well-being of said individual in question may be harmed. 

The body mass index (BMI), a proxy measure, is most often adopted to identify if a person is overweight or obese considering that it is extremely challenging to quantify body fat directly. Additional methods are available to identify people who have 'central' fat distribution-related health hazards and to characterize excess fat in greater detail in unique clinical and scientific contexts. However, BMI continues to be the most popular and convenient approach to diagnosing obesity. 

That said, no one figure can effectively exemplify your personal health. It is oftentimes more accurate to gauge your general health and well-being by how you nurture your physical and mental health. Nevertheless, we dwell in an epoch where medical professionals and other specialists must employ graphs, statistics, and other metrics to establish a common conceptual framework of health. In light of this, your doctor or other healthcare professional will frequently track your body mass index or BMI. It's crucial to keep in mind that while BMI and other parameters like body fat percentage have their uses, exercising your physique and making informed dietary decisions also have an impact on your general health.

The following article aims to thoroughly investigate every facet and dimension of BMI, from what it is to how you may calculate your BMI on your own.

What Is Body Mass Index? 

Perhaps the most common indicator of physical well-being in contemporary human millennia is body mass index, which is given a significant amount of attention in today's world. BMI, or body mass index, is a metric adopted by medical professionals to quantify how much body fat you have based on your height and weight parameters. It can aid in determining risk factors for particular medical diseases. Although BMI isn't always a reliable indicator of body fatness, it can help determine whether an individual has the appropriate weight for their height. In layman's language, BMI is a diagnostic measure that may determine if the patient is underweight, has a healthy weight, is overweight, or is obese. Health hazards can considerably escalate for an individual whose BMI is beyond the recommended range.

Despite the fact that BMI doesn't really precisely measure body fat, exploratory studies have established that it is interrelated with more precise measurements of body fat, including densitometry, bioelectrical impedance, and assessments of skinfold thickness, to name a few. The BMI test is generally a low-cost and simple way to check for weight classes that might cause health issues.

Although BMI often corresponds with body fat, it can occasionally be inaccurate. BMI is not a diagnostic tool for health. To evaluate a person's health state and vulnerabilities, medical professionals employ their BMI as well as other instruments and examinations. When aiming to reduce weight or build lean muscle mass, keeping track of your body fat % is one approach to calibrate your success. However, it doesn't tell the whole picture of your health. You should concentrate your efforts on maintaining a balanced diet and an active lifestyle. You might want to consult your doctor, a licensed dietician, or a professional fitness instructor if you have any qualms or queries regarding your BMI or body fat percentage. They can assist you in comprehending your specific outcomes and collaborate with you to create a strategy that meets your requirements.

What is BMI used for? 

People are divided into four weight groups based on their body mass index. Depending on your BMI, you might be underweight, normal weight, overweight, or obese. While the fact that BMI provides a basic framework for calculating relative body composition, don't be disappointed if you fall into the obese bracket despite being in excellent physical condition. In essence, it aids a typical individual in determining if they fall within the healthy weight range or the unhealthy range. 

1. Healthy Range

The optimum BMI range for most individuals is between 18.5 and 24.9. Only this category of BMI falls into the normal weight range. If you fit this description, give yourselves a congratulatory pat on the back. If you fall into a different group, you may need to alter your diet and exercise routines in order to attain a healthier weight.

2. Unhealthy Categories

Being "underweight" does not essentially mean that you are unhealthy. This category may be easily filled by physically fit individuals with low body fat. The classifications of "obesity" and "overweight" may indicate a more serious problem, yet sometimes physically strong, highly muscular persons fall into these categories.

BMI is economical and simple to compute, making it scalable. It's also important to note that, regrettably, the majority of folks do not fit the rugby or powerlifter stereotypes, despite the fact that this method is unsuitable for gauging fatness in extremely athletic people. Therefore, for the majority of us, a higher BMI is associated with a tendency to carry more body fat, making BMI a reliable benchmark for monitoring weight and health across large populations. However, BMI shouldn't be regarded as the only determinant of a patient’s health condition or advised by medical experts or anybody else for that matter. It needs to be interpreted in light of other data, including blood pressure, fasting insulin and glucose levels, and a genetic predisposition to metabolic illness. 

Benefits Of BMI 

A quick, low-cost, and non-invasive substitute for measuring body fat is BMI. Unlike the other approaches, BMI just considers a person's height and weight, and with the right tools, anyone can have their BMI regularly assessed and computed with fair precision. Listed below are a few benefits of BMI

  • BMI are calculated quickly and effortlessly, employs affordable, commonly accessible equipment, and is simple for customers to comprehend. 
  • BMI can be used as a preliminary assessment framework to determine those who are at higher health risk due to being overweight and having an uneven accumulation of body fat. 
  • Since diabetes and cardiovascular disease (CVD), two major chronic illnesses, are directly correlated with BMI, additional testing for the incidence of diseases is strongly advised for people whose BMI falls outside of the normal parameters, making BMI a crucial indicator of such diseases. 
  • One major benefit of adopting BMI to assess the health risks associated with obesity is that, when conducted in accordance with defined protocols, the measurements required for its calculation—height and weight—can be recorded with exceptional precision. These steps are simple to implement and require minimal technical training.
  • Experts can amass information to investigate and monitor the obesity pandemic by calculating the BMI of a sizable population.Thus the BMI can be a useful instrument in highlighting the dietary pattern that leads to obesity in a large population.
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Drawbacks of BMI 

The use of BMI alone may not always be able to place people into the correct weight category, despite the fact that in many instances it is beneficial for assessing weight-related health risks. Because BMI measures excess weight rather than just abnormal body fat, it can be used as a substitute for measuring body fatness. That said, the use of BMI alone may not always be able to place people into the correct weight category, despite the fact that in many instances it is beneficial for assessing weight-related health risks. Thus, it is imperative to reflect on the clinical restrictions of BMI. The link between BMI and body fat can be influenced by elements including age, sex, ethnicity, and muscle mass. Listed below are a few drawbacks of BMI. 

  • The dispersion of fat among people cannot be determined by BMI, nor can it be differentiated from extra muscle, bone, or fat mass.
  • When addressing persons who are exceptionally fit yet have greater body weight, BMI sometimes causes apprehension and frustration since it doesn't make a distinction between lean muscle and fat mass.
  • The type of fat that a person carries, such as visceral or subcutaneous fat, is not taken into account by their BMI.
  • Your chance of developing certain diseases might also be influenced by your ethnicity. For instance, South Asian people with a BMI of 23, which is typically seen as healthy, may be more susceptible to certain health issues, such as diabetes.
  • Age or sex are not taken into consideration when determining BMI for individuals 20 years of age and older. With the same BMI, women frequently have significantly more body fat than men. Similarly, a younger individual with the same BMI is likely to have less body fat than an older one.

BMI In Adults

Sustaining a healthy body weight has several advantages beyond increased energy and lower clothing sizes. You are also positioned to gain from several quality-of-life aspects by decreasing weight or ensuring a healthy weight. Body mass index (BMI) and waist circumference are two alternative measures of body composition. Another indicator of the dispersion of body fat is the waist-to-hip ratio (WHR). WHR is no longer advised since it is less reliable than BMI or waist circumference. Listed below are a few important pointers of BMI. 

  • Underweight people have a BMI of less than 18.5 kg/m².
  • A healthy BMI ranges from 18.5 kg/m²  to 24.9 kg/m².
  • A BMI of 25.0 to less than 30.0 kg/m² is regarded as overweight. Type 2 diabetes, hypertension, and cardiovascular disease are all more likely to affect people with BMIs in this range.
  • A BMI of 30.0 kg/m² or more is regarded as obese. Cardiovascular illnesses are more likely to affect those with BMIs of 30.0 kg/m² or above.
  • BMI of 40 kg/m² or more is the threshold for morbid obesity.

How To Calculate BMI In Adults 

To evaluate and manage your weight, it may well be helpful to know your body mass index or BMI. Although it is the simplest and most affordable method of measuring body fat, it is not necessarily the most precise method. Your BMI may be calculated in a variety of ways based on the measurements you've taken. Although BMI is not the only aspect people should think about when improving their physical fitness and BMI for men and BMI for women are different, it serves as an excellent place to start. You must be aware of your height and weight in order to calculate your BMI. You may then check your BMI using an online calculator, which will enable you to determine if you are underweight, a healthy weight, overweight, or obese. Alternatively, you might carry out the process manually. The steps are quite simple and straightforward.


Step one:

Measure your height in meters and weight in kilograms.

Step two: 

Divide your weight in kilograms (kg) by the square of your height in meters (m2)


Step one:

Measure your height in inches and weight in pounds.

Step two: 

Divide your weight in pounds by height in inches and multiply it by 703. 

BMI Table For Adults 

The following table lists conventional weight status categories for adults along with BMI ranges.

         BMI            WEIGHT STATUS
Below 18.5             Underweight    
Between 18.5 and 24.9 Healthy        
Between 25.0 and 29.9 Overweight    
Between 30.0 and 34.9 Obese          
Above 40               Morbidly Obese

Understanding The Results

In order to take the appropriate and prompt measures for the greatest possible outcome for your body, it is not enough to just calculate your BMI; one must also be knowledgeable and acquainted about what these values signify. Although scientifically speaking BMI for men and BMI for women must be differenT. Here is a detailed assessment of each score and what it means to you.

1. BMI Of Less Than 18.5:

If your BMI is 18.5, you're on the lower end of the spectrum of the healthy weight range  A BMI of 18.5 may be appropriate for you if you have a naturally small body, but if you have a bigger frame, it may indicate that your bodyweight is too low. Considering you're on the brink of becoming underweight, you must speak with a physician to see whether gaining weight will be beneficial for your health. The amount you'll have to grow will entirely depend on your size and health currently. Irrespective of your weight objectives, you ought to utilize this time to evaluate your way of living. Anyone who practices unhealthy lifestyle behaviors, not only those who are overweight, runs the risk of developing health problems.

2. BMI Between 18.5 And 24.9:

You're considered to be in a healthy weight range if your BMI falls between 18.5 and 24.9. It is the optimal BMI for the majority of adults. This does not imply that you are free to have a carefree life. Even those with healthy BMI ranges ought to work hard and make mindful choices each day to maintain their health and stave off ailments.

3. BMI Between 25.0 and 29.9:

Individuals who have a BMI between 25 and 29.9 would be categorized as overweight BMI by the BMI weight status classifications. Nevertheless, rather than having more body fat, athletes may have a high BMI due to higher muscle mass. However, the terms "obesity" and "overweight" are sometimes used interchangeably, giving overweight the meaning of a BMI of 25 to 29.9. This indicates that in order to prevent deleterious repercussions, immediate action must be performed. Weight loss by healthy eating, increasing physical activity and making other lifestyle modifications are common therapies for obesity. Some persons may benefit from weight-management programs in terms of weight loss or preventing weight gain.

4. BMI Between 30.0 and 34.9:

If your BMI is greater than 30, you are considered severely overweight or obese. Being obese refers to weighing more than is normal for one's height. Obesity is a persistent, dangerous illness that needs utmost care and attention. If you don't reduce weight, you might endanger your health and it is advised that you get guidance from your physician or a dietician. Any area of a person's health that is affected by obesity might be affected. It is linked to a number of diseases, including osteoarthritis, certain malignancies, high blood pressure, type 2 diabetes, sleep apnea, heart attacks, and strokes. Obesity requires urgent medical treatment and must be handled carefully.

5. BMI Above 35:

You are classified as being extremely obese with a BMI of 35. Consult with your doctor to learn about the various surgical options if you have previously attempted diet and exercise without success. Severe obesity can make it challenging to do daily tasks including breathing, sleeping, and walking. Additionally, it can raise your chance of developing cardiovascular disease, type 2 diabetes, a host of other illnesses, and in the most extreme case scenario, death.

BMI In Children & Teens

The term "BMI-for-age" refers to the BMI for children and adolescents, and is gender- and age-specific. Despite the current BMI-for-age classification, it is essential for your child's health that you encourage them to adopt healthy eating patterns and that you consult with your doctor or another healthcare professional as part of regular BMI-for-age monitoring. You can ensure that your child is obtaining or sustaining a healthy weight by monitoring their development trends throughout time. Because your child's height and weight will fluctuate as they become older, using a single BMI-for-age estimate to assess your child's long-term weight status is insufficient. Healthcare professionals should take an individual's BMI into account along with other variables including family background, blood pressure, blood sugar levels, eating habits, and degree of physical activity.

How To Calculate BMI In Children & Teens 

Obesity among children has reached pandemic proportions in both developed and developing nations. Childhood obesity and being overweight are known to negatively affect both physical and mental health. Children who are overweight or obese are much more prone to be overweight into maturity and to experience non-communicable illnesses like diabetes and cardiovascular disease earlier in life. In order to guarantee and provide the greatest health for your child, it is crucial for all parents to be well informed on how to stay current about their child's health and the BMI scale. For prompt, accurate, and hassle-free results, you might use an online calculator similar to the one for adult BMI. 

BMI Table For Teenagers & Children 

Following the BMI calculation for kids and teenagers, the result is stated as a percentile that may be found on a graph for boys and girls or by using a percentile calculator. The most widely employed metric to assess the size and development trends of children and adolescents in the United States is the BMI-for-age percentile growth chart. The following table displays the BMI-for-age weight status groups and accompanying percentiles based on the conclusions of an expert panel.

Less than 5th percentile         Underweight    
Between 5th and 84th percentile   Healthy        
Between 85th and 95th percentile Overweight    
Above 95th percentile             Obese          

What Is BMI Percentile? 

BMI percentile measures underweight, overweight, and the likelihood of gaining weight in children and adolescents. Body fatness in children fluctuates as they get older. Boys and females are different from one another. These factors make the BMI percentile for adolescents particular to age and gender. Your physician will likely utilize growth charts that are customized to each gender. Similar to how it is determined for adults, BMI is also represented as a percentile, which may be found on a graph or by utilizing a percentile calculator. These percentiles represent a child's BMI in comparison to other kids their own age and gender. Although it is computed using the same method for both children and adolescents, BMI is evaluated differently for each group. The BMI values of children and teenagers are stated compared to other youngsters of the same sex and age because of changes in their weight and height with age and their relationship to body fatness. 

Understanding The Results 

The next crucial step after learning your child's BMI percentile is to comprehend what these numbers signify since they suggest the best course of action to take for your child's health. A thorough analysis of each category and its BMI percentile is provided below so you may make an informed decision regarding your children's health.

1) Less Than 5th Percentile:

A child is considered underweight if their weight falls inside the lowest fifth percentile for their height. Doctors clinically classify a child as being underweight based on their height as well as how they compare to other kids their age. Because their growth has to catch up with peers, preterm babies sometimes have low birth weights. But insufficient food intake is frequently the cause of being underweight in older kids. Picky eating might or might not be the cause of this. A number of medical conditions can also reduce appetite or prevent the absorption of nutrients. Despite their small size, children require the energy and minerals that come from a diverse and nutrient-dense diet in order to thrive. And as parents, you are responsible to provide them with that.

2) Between 5th And 84th Percentile:

Your youngster is robust and at the ideal weight if they fall into this category. In light of this, it's critical to support your child in keeping this up in the safest and smoothest way possible without placing undue pressure on them. Health is a delicate topic, and for children who don't know anything about food, it may be perplexing and difficult. In order for your child to have a positive and healthy relationship with food and weight, it is your responsibility as parents to guide them along the health path.

3) Between 85th And 95th Percentile:

If your child fits this classification, they are overweight and in danger of becoming obese. Youngsters who are overweight are more common today, which indicates that adolescents and children are more likely to develop chronic disorders linked to obesity. A youngster who is overweight is more likely to develop a range of illnesses and disorders. Children and adolescents who are overweight are more likely to grow up to be overweight or obese. It is quite difficult to escape the cycle. Cancer, stroke, and cardiovascular disease—the top three causes of mortality in adults—are established risk factors for a poor diet and a sedentary lifestyle.

4) Above 95th Percentile:

In the event that your child fits this description, they are obese.  It's especially concerning because childhood obesity frequently sets kids up for health issues like diabetes, high blood pressure, and high cholesterol, which were formerly thought to be the domain of adults. Additionally, depression and low self-esteem in children can result from obesity. Improving your family's nutrition and physical activity practices is one of the greatest ways to combat childhood obesity. Obesity in children can be treated and prevented, which can help safeguard both your child's present and future health.

Benefits Of A Healthy Weight

Because persons who are overweight or obese have a higher risk of developing heart disease and stroke, sustaining a healthy weight is absolutely crucial. Short-term diets are not the most significant component in keeping a healthy weight. Making long-term lifestyle adjustments is the goal. This entails three things: a nutritious diet, maintaining a balance between calories consumed and expended, and frequent activity. Along with feeling good, staying a healthy body weight and BMI provides a lot of advantages. Maintaining a healthy weight not only lowers the risk of heart disease, diabetes, stroke, and high blood pressure, but also of numerous other cancers. Regardless of where you stand in your weight reduction journey, sustaining your target body weight can be challenging. Every positive step matters if you're overweight since shedding even a handful pounds can boost your health! Here are 10 factors that make maintaining a healthy weight imperative as well as important.

  • Improved Heart Health
  • Lower Risk Of Diabetes
  • Lower Risk Of Cancer
  • Prevent Osteoarthritis
  • Increased Fertility
  • Discomfort Relief
  • Better Mental Health
  • Better Sleep
  • Longer Lifespan
  • Optimised Immunity Levels

Health Risks Of Having Extra Weight

Compared to individuals who are at a healthy body weight, those who are overweight or obese are more likely to develop a wide range of catastrophic illnesses and medical issues. Nearly every element of health is negatively impacted by excess weight, particularly obesity, from cognition and mood to sexual and pulmonary function. Obesity increases the likelihood of numerous fatal and disabling conditions, such as diabetes, heart disease, and various malignancies. It accomplishes this through a number of different channels, some as simple as the mechanical strain of bearing more weight and others involving subtle adjustments to hormones and metabolism. Additionally, obesity reduces life expectancy and quality of life while also raising personal, societal, and healthcare expenses. The excellent news is that losing weight can reduce several hazards associated with obesity. For those who are obese, losing just 5 to 10 percent of body weight has significant positive health effects. Listed below are a number of health risks that come alongside obesity and being overweight.

  • Type 2 diabetes.
  • Coronary heart disease.
  • Many types of cancer
  • High blood pressure (hypertension).
  • Osteoarthritis
  • Low quality of life.
  • Body pain and difficulty with physical functioning
  • High LDL cholesterol, low HDL cholesterol, or dyslipidemia)
  • Sleep apnea and other breathing problems.
  • Stroke.
  • Gallbladder disease.
  • Mental illness 

Other Ways To Measure Health 

People monitor anything and everything, including steps and calories. However, when it concerns health, there is one number that is consistently noted, discussed, and condemned –  body weight. People frequently believe that this number is the only one that counts when it pertains to their health because of the consistent focus on it. It's not, though. Essentially, a few distinct measurements of your health are determined by what is known as biomarkers. You may gauge your health more accurately by counting a few key components of your everyday life rather than stepping on the scale. Listed below are the top five ways to measure your health.

1. Waist circumference

Your waist circumference measurement may aid in your understanding of certain health hazards associated with obesity. Waist measurements are frequently used by medical professionals to check individuals for potential weight-related health issues. Waist size is one sign that may hint at some health concerns, however, it is not utilized to diagnose any disorders or diseases on its own, despite being a useful tool. While doctors and other medical professionals could use this technique in the office, you can measure your own waist circumference in the comforts of your home

2. Blood Pressure

To safeguard your general health, one must also pay careful attention to and make an effort to regulate your blood pressure. Atherosclerosis is a highly significant condition that can develop from uncontrolled hypertension. In essence, having extremely high blood pressure may cause harm to critical bodily veins. Because it may not always present with overt symptoms, high blood pressure is referred to as the "silent killer" and can raise the risk of heart attack or stroke. It's important to keep your blood pressure well within standard parameters, even if you don't  need to check it every day.

3. Cholesterol Levels

Recognizing your "good" and "bad" cholesterol levels have important clinical implications. Generally speaking, by the time you are around 20, your doctor must examine your cholesterol levels at least once every five years. This figure might need to be examined more frequently if you have other significant vulnerabilities. One of the most crucial indicators of excellent health is this number since it may also point to a high-risk factor for heart disease.

4. Blood Sugar Level

A sugar levels test measures the amount of glucose (sugar) in a person's blood and detects diabetes. While fasting, normal blood glucose ranges from 70 to 99 mg/dL (3.9 to 5.5 mmol/L). Higher levels could be a sign of diabetes or pre-diabetes. The most pertinent bit you can do to control type 1 or type 2 diabetes and your general health is to regularly monitor your blood sugar levels. You'll be enabled to observe what influences your levels to rise or fall, such as consuming certain meals, taking medication, or engaging in physical activity. With the help of this knowledge, you can decide on the optimum diabetes management strategy in collaboration with your medical team.

5. Hours Spent Sleeping

Scientists advise people to try to get eight to nine hours of sleep each night. If you can get this much sleep, you reduce your chance of developing an incidence of chronic medical disorders. Lack of sleep has been connected to diabetes, heart disease, and even high blood pressure. Recent studies have shown a relationship between sleep debt and issues with heart health. In one research, getting too little sleep increased the risk of heart attack and stroke by an amount comparable to that of smoking. Thus the hours you spend sleeping is an important marker of your overall health.


Your risk of malnutrition increases if your body mass index is in the low range. Perhaps your body isn't processing essential minerals effectively, or maybe you're simply not consuming sufficient calories to sustain your level of exercise. In contrast, a BMI that is on the upper end warns your doctor that you have a higher risk of developing heart disease, diabetes, and several types of cancer compared to anyone having a normal body mass index. Your doctor may connect you with a licensed dietician who may assist you in regaining control of your weight and lowering your likelihood of incurring health issues. BMI is unquestionably not a perfect indicator of health when used alone. Infact the biggest flaw would be that BMI for men and BMI for women are different. However, it's still a good way to kickstart serious illnesses that are made more probable by being overweight or obese.  Simply put, it's a good habit to be aware of your BMI. But it's equally critical to be aware of its constraints.


1. How to calculate BMI?

  •  BMI = mass (kg). height2 (m) 

2. What is the normal BMI for men?

  • Between 18.5 and 24.9

3. What is the normal BMI for women?

  • Between 18.5 and 24.9

4. What should be the normal BMI of a person?

  • Between 18.5 and 24.9

5. Is BMI the same for adults and children?

  • No.  Although it is computed using the same method for both children and adolescents, BMI is evaluated differently for each group. 

6. Why is BMI different in adults and children?

  • The BMI values of children and teenagers are stated compared to other youngsters of the same sex and age because of changes in their weight and height with age and their relationship to body fatness, unlike adults.

7. What is a normal BMI for a child?

  • Between 5th and 84th percentile

8. What BMI defines obesity in adults?

  • Between 30.0 and 34.9


This website's content is provided only for educational reasons and is not meant to be a replacement for professional medical advice. Due to individual differences, the reader should contact their physician to decide whether the material is applicable to their case.