BMI Calculator (Body Mass Index Calculator)

What is a BMI Calculator?

BMI is an acronym for Body Mass Index.

Body Mass Index (BMI) is a conditional indicator used to assess the degree of obesity or lack thereof in individuals.

It is sometimes called the Quetelet index or the Ketele index (French and English Quetelet) in honor of the Belgian mathematician and statistician Adolphe Quetelet who proposed it more than 150 years ago.

How a BMI Calculator Works

A BMI calculator calculates body mass index by dividing the weight into several kilograms by height in meters squared.

BMI = Human weight (in kilograms): Height (in meters) squared

For example, for a person with a weight of 73 kg and a height of 172 cm, the BMI will be as follows: BMI = 73: (1.72 x 1.72) = 24.68 kg / m2.

Measured in kg / m2.

The body mass index is convenient for the numerical assessment of the state of the patient’s body. In most cases, it correctly displays the presence and degree of obesity.

To calculate your body mass index (BMI) via the BMI calculator, enter the values ​​of height and your weight with precision to tenths, then the result of the calculation will be the most accurate.

World Health Organization BMI Classification

Here is the WHO – World Health Organization classification in adults who are underweight, overweight and obese about body mass index

BMI< = 18.4 AND <25: Underweight

BMI> = 18.5 AND <25: Normal weight

BMI> = 25 AND <30: Overweight

BMI> = 30 AND <35: Obesity I degree

BMI> = 35 AND <40: Obesity grade II

BMI> = 40: Obesity grade III

A BMI calculator output is also categorized as shown above

BMI Calculator (Body Mass Index)

BMI Calculator (Body Mass Index)

BMI <18.5: Underweight

BMI of less than 18.5 classifies you into the underweight category according to WHO BMI classifications.

The desired BMI is 18.5 – 24.9. Therefore you will need to gain some weight to be in the normal BMI category. BMI Less than 16.5 is considered severely underweight. Urgent consultation with a specialist is needed!

Often weight deficiency is caused by diseases of the gastrointestinal tract, or endocrine and hormonal disorders. In such cases a detailed medical examination is necessary. Another reason might be genetic.

Make sure to have a consultation with a specialist. Their recommendations are mostly simple: eat well, get enough sleep, exercise, quit smoking and drinking alcohol, and learn how to properly respond to stress.

Meals should be 5-6 times a day, with a sufficient amount of protein and carbohydrates, dairy products of normal fat content. The diet should include high-calorie meals. Try to include nuts and dried fruits as snacks.

Desired BMI 18.5 – 24.9

Your weight is in the normal range.

All you should do is keep it in that range with a healthy diet and moderate exercise.

Overweight: 25 – 29.9 (Pre-obesity)

Consultation with a specialist might be required. First-line management is lifestyle modifications which include dietary changes – calorie restriction diets and regular physical activity

Obese (Obesity class I) BMI: 30 – 34.9

According to the BMI classification, you are in the first obesity category

Consultation with a specialist is required to evaluate the health status and risks of a patient,  and further come up with an effective management plan.

Management can be

  • Non-medical – important lifestyle modifications like dietary changes consisting of calorie restriction, healthy diets and daily regular physical activity
  • Medical therapy – medications prescribed by your health-care physician to help reduce weight and minimize the risk of obesity-related complications
  • Surgery – bariatric surgery, which involves making changes to your digestive system to aid in weight loss

Obese (Obesity class II) BMI:  35 – 39.9

According to BMI classification, You are in the second class obesity category

Consultation with a specialist is required to evaluate the health status and risks of a patient and further come up with an effective management plan. BMI of more than 35 is referred to as severe obesity

Management can be

  • Non-medical – important lifestyle modifications like dietary changes consisting of calorie restriction, healthy diets and daily regular physical activity
  • Medical therapy – medications prescribed by your health-care physician to help reduce weight and minimize the risk of obesity-related complications
  • Surgery – bariatric surgery, which involves making changes to your digestive system to aid in weight loss

Obese (Obesity class III) BMI: >/= 40

According to BMI classification, You are in the third class obesity category

Consultation with a specialist is required to evaluate the health status and risks of the patient and further come up with an effective management plan.

A BMI of more than 40 is referred to as  morbid obesity

A BMI of more than 50 is referred to as extreme obesity

  • Non-medical – important lifestyle modifications like dietary changes consisting of calorie restriction, healthy diets and daily regular physical activity
  • Medical therapy – medications prescribed by your health-care physician to help reduce weight and minimize the risk of obesity-related complications
  • Surgery – bariatric surgery, which involves making changes to your digestive system to aid in weight loss.

Surgery is mostly recommended if BMI is more than 40 and there’s no success with dietary and lifestyle changes

How is obesity defined?

Obesity is abnormal or excess fat deposition in the subcutaneous tissue and other tissues of the body, which presents a health risk.

How to identify the cause of obesity

For any class of obesity, consultation and examination by an endocrinologist and nutritionist is recommended

Blood tests – lipid profile, fasting glucose, liver function tests, tests for the levels of uric acid, creatinine, thyroid hormones, vitamin D, iron (profile for anemia), ECG, Ultrasound.

Based on the results of the examination, an endocrinologist or nutritionist will be able to assess the risk of developing obesity-related pathologies – hypertension, heart disease, joints, fatty liver degeneration, etc.

The doctor will select an adequate treatment regimen for the first, second, or third class of obesity.

How does obesity affect health?

Currently, a significant amount of factual evidence has been accumulated indicating that obesity contributes to the development of several chronic non-communicable diseases.

  • The cardiovascular system

Fat is deposited around the heart and in the walls of blood vessels. The ability of the heart muscle to push blood into large vessels gradually decreases.

In obese patients, arterial hypertension and coronary heart disease occur 2-3 times more often than in those with normal BMI.

  • Respiratory system.

Fatty tissue “supports” the diaphragm from the inside, as a result of which obese patients cannot breathe deeply, their breathing is shallow.

This, in turn, is a risk factor for the development of bronchitis, pneumonia, and apnea. They are most severe in smokers.

  • The gastrointestinal tract.

Problems arise along the entire length of the gastrointestinal tract, from stomatitis to hemorrhoids. Due to the stretching and weakness of the anterior abdominal wall, all abdominal organs, mainly the stomach, go down and stretch. Intestinal motility suffers, hence there is flatulence and constipation.

Fatty degeneration of the liver and pancreas occurs. Almost half of the obese people are diagnosed with cholecystitis, sometimes with the formation of stones.

  • Endocrine system.

Obesity is a well-known risk factor in the development and progression of type 2 diabetes since the abnormal metabolic state associated with obesity markedly increases insulin resistance and diminished insulin sensitivity.  

A paradoxical situation is created where there is a high level of both glucose and insulin in the blood, and the cells “starve”.

Diabetes mellitus type 2 is sometimes called “obesity diabetes” for a reason. Obesity causes the general hormonal balance of the body to be disturbed, not only the pancreas but the thyroid gland, as well as the testicles and ovaries, suffer.

  • Musculoskeletal system

Obesity significantly raises the risk for osteoarthritis and osteoporosis, which themselves predispose sufferers to brittle bones and fractures, hence diminishing one’s quality of life.

  • How to manage obesity

Individual selection and correction of the diet by one’s health condition is required.

Lifestyle modification is the first-line treatment of obesity.

Recommendations mostly are to limit calorie-rich foods: fats, sweets, baked goods, fast food, alcohol.

Increase consumption of plant-based food like fruits vegetables and meats.

It is recommended to drink 1 liter of water daily to stay hydrated and aid in the weight loss process.

Get regular physical activity (60 minutes a day for children and 150 minutes a week for adults)

There are numerous types of diets with meal plans you can try out on: dietsmealplan.com

A basic BMI calculator formula works with general assumptions without considering your specific condition, age and ethnicity. Always consult your physician before taking any action that is based on an output of a BMI calculator.

References:

https://www.cdc.gov/obesity/index.html

https://www.who.int/health-topics/obesity

https://www.cdc.gov/healthyweight/assessing/bmi/adult_bmi/index.html

https://www.who.int/data/gho/data/indicators/indicator-details/

https://www.cdc.gov/healthyweight/assessing/

https://www.cdc.gov/healthyweight/assessing/bmi/adult_bmi/