Introduction to the body mass index (BMI)
Body Mass Index (BMI) is widely used as an indicator of body fat content. Your weight alone is not sufficient to establish if you are in a healthy weight range. For example, a tall but slender person can weigh more than a short but plump individual. But the former may enjoy better health as long as their weight is suitable for their height. The ideal weight is also likely to differ for men and women of similar heights.
How then do you know whether you fall in the healthy weight range or not? Your BMI solves this confusion. It correlates your weight with your height and evaluates whether your weight is appropriate for your stature. You can use a BMI calculator to find out your BMI.
Although not an exact measurement of body fat percentage, in most cases, BMI is a reliable tool for establishing risk levels for illnesses, especially ailments related to excess body fat. Many healthcare professionals use BMI to determine effective doses for medicines. Often people with a higher BMI need higher doses. Hence, it is crucial to be aware of your BMI to ensure your overall wellness.
Why Use a BMI Calculator?
Using a BMI calculator is a convenient way to determine your BMI score quickly. Below are some key reasons to use this tool:
Health Monitoring: A BMI calculator helps you keep track of your health. It enables you to spot potential health issues early on so you can take action to stay healthy. The calculator can provide you with the opportunity to take proactive measures to maintain and enhance your health.
Fitness Goals: A BMI calculator becomes a valuable companion in helping you achieve your fitness goals. It allows you to gauge your physical progress accurately. By regularly checking your BMI, you can ensure that your fitness endeavours align with your specific goals.
Weight Management: A BMI calculator can be ideal for effective weight management. It assists you in setting realistic weight goals and a path towards a healthier weight. It helps you establish a suitable weight management strategy with achievable milestones over time.
Health Assessment: You can gain valuable insights into your overall health status by understanding your BMI. The online BMI calculator takes into consideration your height and weight and offers a quick assessment of your overall health. It highlights potential health risks and areas where you can improve your holistic well-being. This helps you stay fit, active and healthy.
How to calculate BMI
If you want to calculate your BMI, you have to find out your weight and height first. Once you know these values, you can arrive at the result by following the two steps mentioned below:
- Multiply your height by itself (height X height).
- Divide your weight by the answer you get in the first step.
The equations for calculating the BMI are as follows:
International System of Units (SI)
BMI = weight (kg) ÷ (height (m))2
Example:
For a 177 cm (1.77 m) individual weighing 75 kg, BMI = 75 / (1.77 * 1.77) = 75/ 3.13 = 23.96
Imperial System
BMI = weight (lb) ÷ (height (inches)) 2 × 703
Example:
For a 160-pound, 5’8” (68”) individual weighing 75 kg, BMI = (160/ 68*68) * 703 = (160/4624) * 703 = 24.3
What are the health risks related to being overweight?
Excess weight brings with it countless health complications, some of which can be fatal. A higher BMI than average (over 25) is associated with increased risks for diseases like:
- Type 2 diabetes
- Heart conditions
- Higher levels of LDL cholesterol and lower count of HDL cholesterol in the blood, increasing chances of coronary artery diseases and heart attacks
- High triglycerides
- Stroke
- High blood pressure
- Gall bladder-related complications
- Insulin resistance
- Osteoarthritis or breakdown of joint cartilage leading to painful joints
- Sleep apnea or intermittent breathing obstruction during sleep
- Atherosclerosis or building up of cholesterol deposits (plaques) in blood vessels (arteries)
- Skin health problems like skin tags, darkening of the skin
- Breathing trouble
- Poly-cystic ovarian disease in women leading to reduced fertility and other menstrual irregularities
- Hernia
- Varicose veins
- Cataract
- Gout
- Stress incontinence or urge to urinate frequently
- Clinical depression and other mental health issues
- Certain types of cancer (breast, colon, endometrial, gall bladder, kidney, liver)
How to calculate BMI
For adults over the age of 20 years, BMI values are grouped into the following weight status categories1:
BMI | BMI Weight status |
Below 18.5 | Underweight |
18.5–24.9 | Normal weight |
25–29.9 | Overweight |
30–35 | Obese |
Over 35 | Morbid obesity |
BMI for Children
In children, body fat content changes with age. It is also normal for teenage girls to have more body fat than boys. BMI calculation for children follows the sameformula as adults. But the value is then plotted on standard gender-specific BMI-for-age percentile charts for children. It determines the child's weight status compared to children of the same gender and age.
For example, a 25th percentile BMI for a 6-year old female child would indicate that the child's weight is higher than 25% of girls aged 6.
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