BMI Calculator: A Tool for Body Weight Assessment
What is BMI?
BMI stands for Body Mass Index, and it serves as a valuable tool for assessing how your weight aligns with your height. Simply put, it's a number that provides insight into whether you fall into categories like "underweight," "normal weight," "overweight," or "obese." It's calculated by dividing your weight in kilograms by the square of your height in meters. This single number can offer a quick snapshot of your overall weight status and, to a certain extent, your overall health.
Using the BMI Calculator
Step 1: Input Your Details. Fill in your age, sex, height and weight in the form below.
Step 2: Calculate Your BMI. Hit the "Calculate BMI" button to receive your BMI score.
Step 3: Interpret Your BMI. Your BMI score will fall into one of the four categories mentioned earlier.
Step 4: Find resources online to understand what your BMI score means for your health.
|Classification||BMI range - kg/m2|
|Severe Thinness||< 16|
|Moderate Thinness||16 - 17|
|Mild Thinness||17 - 18.5|
|Normal||18.5 - 25|
|Overweight||25 - 30|
|Obese Class I||30 - 35|
|Obese Class II||35 - 40|
|Obese Class III||> 40|
Interesting Facts about BMI
Let's explore some intriguing BMI insights. If we look at worldwide BMI data (maintained by WHO), a host of fascinating facts come to light. For instance:
- The population group with the highest mean BMI in the world is Samoan females, reaching an astounding 34.1. According to BMI calculations, the average Samoan woman is obese, weighing nearly 100kg/220lbs, with a height of 167cm/5ft5 tall.
- On the other hand, when we consider men, those from the Cook Islands take the lead with a mean BMI of 32.7. with the highest mean BMI can be found at Cook Islands (32.7). An average Cook Islands man tips the scales at over 100kg/220lbs and stands at 178cm/5ft10. Apparently, "Cook-Islanders" like to cook.
- If we venture to Ethiopia, we find the leanest group on the planet - Ethiopian men - with a BMI of 20.1. Ethiopian men typically fall into the "normal weight" category, weighing around 55kg/121lbs and measuring 168cm/5ft6 in height.
- The record for the lowest mean BMI among women is shared by Ethiopia, Eritrea and Madagascar, all at 21.1. In these countries, the women weigh roughly 50kg/110lbs and are 153-157cm/5ft1 tall.
- Ethiopia, with its mean BMI of 20.1, boasts the title of the "slimmest" nation, with an average weight of 54kg/119lbs. On the opposite end of the spectrum, the Cook Islands claim the spot as the "heaviest" country, clocking in at 32.9 and an average weight of 98kg/217lbs.
- These statistics reveal the immense diversity within our species. For instance, the women of Madagascar weigh approximately 53% less than their counterparts in the Cook Islands (though they are, to be fair, 14cm/5.5 inches shorter). Similarly, Ethiopian men weigh around 54% less than Cook Islands men (but, again, are about 10cm/4 inches shorter on average).
- If we turn our attention to the United States, we find that American men rank 13th on the global obesity scale (28.8), while American women are in the 30th spot (28.9). While this is not bad for a country often described as "most obese", it appears both genders are competing to join the obesity "club."
- In a global context, women tend to have a higher BMI than men, a pattern observed in approximately 70% of countries worldwide.
- Eswatini and South Africa present the most significant gender gap in BMI. Men in these countries maintain a "normal weight," while women are approaching the "obesity" threshold. The BMI difference between the genders in these nations is a "robust" 4.4.
- Switzerland, interestingly, flips the script, with Swiss women registering as "normal weight" (23.7), while Swiss men are just slightly overweight (26.7).
- What's noteworthy is that in many developed European countries, men have higher BMIs than women. The top 15 countries with the greatest difference in this regard include Switzerland, Haiti, Spain, Austria, Japan, Denmark, Italy, Slovakia, Hungary, France, Czech Republic, Iceland, Germany, Poland, and Cyprus. In most of these places, men generally tip the scales as overweight, whereas women in the top seven countries maintain a healthy weight.
- China stands out in terms of healthy BMIs; both Chinese men and women fall within the "healthy" range. This distinguishes China among other so-called superpowers.
- Surprisingly, only 53 countries out of 193 manage to keep both their male and female populations in the "normal" category.
- Canada, despite its North American location, exhibits a BMI profile more aligned with European nations. When compared to the USA (28.9), Mexico (28), and certain heavyweight Caribbean countries, Canada's mean BMI of 26.9 appears more in line with the European Union.
- The United States is a rare case where BMI equality between the sexes prevails. They are among the roughly ten countries where men and women have similar BMI values. Others on this list include Uruguay, New Zealand, Slovenia, Nepal, or Vietnam.
- Contrary to popular belief, the United States doesn't top the global obesity charts. Thanks to the World Health Organization's inclusion of several tiny island microstates, the USA occupies the 20th spot. Mexico ranks 27th. Nevertheless, the USA holds the distinction of being the most "out-of-shape" superpower. Among very high per capita income countries, only Qatar surpasses the USA in terms of obesity rates.
And one sad fact: On a global scale, over 2.8 million people lose their lives each year due to complications stemming from overweight or obesity. Shockingly, an estimated 35.8 million DALYs (2.3% of global DALYs, or Disability-Adjusted Life Years) result from these weight-related issues. This is way too many millions too many.
|Antigua and Barbuda||26.7||25.7||27.7|
|Bolivia (Plurinational State of)||26.6||25.3||27.7|
|Bosnia and Herzegovina||25.8||26.4||25.1|
|Central African Republic||22.9||22||23.7|
|Democratic People's Republic of Korea||24.1||24.2||24|
|Democratic Republic of the Congo||22||21.3||22.6|
|Iran (Islamic Republic of)||26.1||25.2||27|
|Lao People's Democratic Republic||22.9||22.7||23.1|
|Micronesia (Federated States of)||29.7||28.1||31.4|
|Papua New Guinea||25.6||25.3||26|
|Republic of Korea||23.8||24.4||23.1|
|Republic of Moldova||27||26.6||27.3|
|Saint Kitts and Nevis||29.5||28.2||30.7|
|Saint Vincent and the Grenadines||27.2||26.3||28.2|
|Sao Tome and Principe||24.8||23.9||25.6|
|Sudan (until 2011)||24.7||23.1||25.9|
|Syrian Arab Republic||28.3||27.4||29.2|
|The former Yugoslav Republic of Macedonia||26.8||27.3||26.2|
|Trinidad and Tobago||27.6||26.6||28.6|
|United Arab Emirates||28.4||28||29.4|
|United Kingdom of Great Britain and Northern Ireland||27.1||27.3||27|
|United Republic of Tanzania||23.2||22.3||24.1|
|United States of America||28.9||28.8||28.9|
|Venezuela (Bolivarian Republic of)||26.7||26.6||26.8|
The Utility of BMI
BMI can help you (or your doctor) to:
1. Identify Potential Health Risks. BMI is your initial step in spotting health concerns related to weight, such as heart disease, diabetes, and more.
2. Track Weight Changes. It provides a baseline measurement for tracking changes in weight over time, revealing if your weight management efforts are paying off.
3. Set Realistic Goals. If a healthier weight is your goal, BMI provides a starting point for establishing achievable objectives and monitoring your progress.
BMI is very valuable when applied to a larger population sample. For instance, in global context it can be used to identify and compare obesity rate, trends and distribution among nations.
Limitations of BMI
Most adults aged 18 to 65 seeking a general overview of their health and weight status can find BMI useful. However, it's important to note that BMI has its limitations, and the results may not provide an accurate picture, particularly for specific groups such as athletes, bodybuilders, pregnant women, or older individuals. Among the limitations of BMI as a screening tool are:
1. Precision Issues. BMI doesn't consider factors like muscle mass, bone density, or fat distribution, potentially misclassifying individuals with high muscle mass as "overweight" or "obese," even if their body fat percentage is low.
2. One-Size-Fits-All. BMI treats all weight the same, whether it's from fat or muscle, and doesn't consider individual variations in body composition.
3. Not for Kids. Children and teenagers have their own BMI calculations, so their scores aren't directly comparable to those of adults.
BMI is a valuable tool for assessing weight and potential health risks for many individuals. While it has its limitations, it remains a useful starting point for anyone looking to gauge their general health. Because BMI was designed for individuals with average lifestyles, it provides a reliable aggregate picture of obesity rates and trends by country (or any larger population samples).
NOTE: Remember that BMI is just one of many factors to consider, and it's always a good idea to consult with a healthcare professional for a comprehensive evaluation of your health.
DISCLAIMER: Obesity rates can change over time. To get the most current information on obesity rates by country, you can refer to reports and data from organizations such as the World Health Organization (WHO) or the Centers for Disease Control and Prevention (CDC) in the United States. The content of this page is considered general knowledge and is provided without endorsement.