BMI Calculator

The Body Mass Index (BMI) is a metric that uses a person's height and weight to determine their level of fatness or thinness. It's a standard measure of whether or not someone is at a healthy weight relative to their height.

In particular, the range in which the result derived from BMI calculation falls is used to classify a person as underweight, normal weight, overweight, or obese. This BMI range may be further subdivided into categories like "very underweight" and "extremely obese," depending on variables like location and age.

Although body mass index (BMI) is not a perfect indication of healthy body weight, it is helpful in determining whether further testing or action is necessary due to concerns about overweight or underweight. See the table below for an explanation of the calculator's BMI categories.

Obesity and its dangers

Many dangerous illnesses and health problems are associated with being overweight. The CDC has compiled a list of such dangers, which follows:

  1. An issue with one's blood pressure
  2. Increased levels of LDL cholesterol, often known as "bad cholesterol," decreased levels of HDL cholesterol, sometimes called "good cholesterol," and elevated triglyceride levels are all symptoms of this condition.
  3. Type II Diabetic.
  4. Stroke.
  5. Disease of the Gallbladder.
  6. Osteoarthritis, a degenerative joint disease that occurs when cartilage in the joints breaks down.
  7. Obstructive sleep apnea and other breathing disorders.
  8. Several types of cancer (endometrial, breast, colon, kidney, gallbladder, liver).
  9. Subpar quality of life.
  10. Problems in the mind may range from severe depression and anxiety to mania and schizophrenia.
  11. Discomforts and challenges performing routine bodily tasks.
  12. A higher death rate compared to those of normal weight.

As can be seen from the list above, being overweight may have serious and even deadly consequences. To be healthy, most people should aim for a body mass index (BMI) of less than 25, although it's always best to check in with a doctor first.

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Dangers of Being Underweight


The hazards that come along with being underweight are as follows:

  1. Anemia, fatigue, and other symptoms of malnutrition (lowered ability to carry blood vessels)
  2. Because of osteoporosis, a disorder that weakens bones, the likelihood of a fracture is elevated.
  3. Weakening of the immunological system.
  4. Challenges associated with maturation and advancement, especially among young people.
  5. Hormonal imbalances may cause problems with a woman's ability to reproduce by interfering with her menstrual cycle. Miscarriage rates are greater in the first trimester for underweight women.
  6. Prospective surgical problems.
  7. A higher death rate compared to those of normal weight.
  8. Anorexia nervosa, like other eating disorders, has its own set of dangers, and underweight people should be aware of them. If you or someone you love could be underweight, it's important to contact a doctor, especially if the cause is puzzling.

The Body Mass Index's Limitations

While body mass index (BMI) has been shown to be a helpful measure of healthy weight, it is not without its flaws. The body mass index is merely an estimate and does not take into consideration muscle mass or fat. Due to the large range of body types and the different ways in which muscle, bone mass, and fat are distributed, BMI alone is not sufficient for establishing whether or not a person is at a healthy weight.

Affecting adults:

Despite its widespread usage, BMI is limited in its ability to predict health outcomes since it measures only fat accumulation rather than lean muscle mass. Age, sex, ethnicity, muscle mass, body fat percentage, and exercise level are only few of the many variables that might affect BMI. An elderly individual, for instance, who is of a normal weight but leads a sedentary lifestyle, may have excessive body fat despite their normal weight. While a younger individual with a greater muscle composition and the same BMI would be regarded healthy, this would be labelled unhealthy. It is conceivable that athletes, and notably bodybuilders, who are deemed overweight because muscle is heavier than fat are really at a healthy weight for their body composition. The Centers for Disease Control and Prevention generally state:

  • Body fat percentages in the elderly are often higher than those in younger persons with the same BMI.
  • Women often have a higher percentage of body fat than males do while having a same body mass index.
  • It's possible that muscle-bound people and elite athletes' body mass indexes are greater than average because of all that extra muscle.

When it comes to kids and teens:

Children and teenagers may be subject to the same limitations on BMI's usefulness as adults. Children's body mass index (BMI) and percentage of body fat may be affected by factors such as height and sexual maturity. Children whose BMI is elevated due to increasing levels of either fat or fat-free mass are less accurately represented by BMI than children whose BMI is elevated due to obesity (all body components except for fat, which includes water, organs, muscle, etc.). Differences in body mass index (BMI) may also be attributable to fat-free mass in lean children.

However, for 90–95% of the population, BMI is an accurate indicator of body fat and may be used successfully in conjunction with other metrics to establish an individual's appropriate body weight.