What is the body mass index?
The Body Mass Index (BMI) is a widely used measure to estimate body tissue mass—encompassing muscle, fat, and bone. It categorizes individuals as underweight, normal weight, overweight, or obese based on their BMI value.
BMI serves as a screening tool to assess whether a person is underweight, has a healthy weight, or is carrying excess weight or obesity. A BMI outside the healthy range may significantly elevate health risks.
BMI is universally calculated in kilograms per square meter (kg/m²), using the formula: weight (kg) / height² (m²). In imperial units, the formula becomes BMI = (weight in pounds × 703) / height² (in²)
Categories of BMI values
A BMI of less than 18.5 indicates underweight status, which may require weight gain. Consulting a doctor or dietitian is recommended for guidance.
A BMI of 18.5-24.9 suggests a healthy weight relative to height. Maintaining this weight can reduce the risk of serious health problems.
A BMI of 25-29.9 indicates being slightly overweight, and weight loss may be advised for health reasons. Seeking advice from a doctor or dietitian is recommended.
A BMI over 30 suggests obesity, which may pose significant health risks if weight loss is not addressed. Consulting a doctor or dietitian for advice is recommended.
Statement Summary
| CATEGORY |
BMI (Kg/m2) |
BMI PRIME |
|
from |
to |
from |
to |
| Very severely underweight |
- |
15 |
- |
0.6 |
| Severely underweight |
15 |
16 |
0.6 |
0.64 |
| Underweight |
16 |
18.5 |
0.6 |
0.74 |
| Normal (Healthy Weight) |
18.5 |
25 |
0.74 |
1 |
| Overweight |
25 |
30 |
1 |
1.2 |
| Obese Class I (Moderately obese) |
30 |
35 |
1.2 |
1.4 |
| Obese Class II (Severely obese) |
35 |
40 |
1.4 |
1.6 |
| Obese Class III (Very severely obese) |
40 |
45 |
1.6 |
1.8 |
| Obese Class IV (Morbidly Obese) |
45 |
50 |
1.8 |
2 |
| Obese Class V (Super Obese) |
50 |
60 |
2 |
2.4 |
| Obese Class VI (Hyper Obese) |
60 |
- |
2.4 |
- |
A. Importance of BMI (Body Mass Index): (Patient Education)
Body Mass Index (BMI) is a widely used tool to assess whether an individual has a healthy body weight for a given height. It is calculated by dividing a person's weight in kilograms by the square of their height in meters (kg/m²). While BMI does not directly measure body fat, it serves as a useful screening indicator of potential health risks associated with being underweight, overweight, or obese.
Consequences of Overweight & Obesity:
Overweight and obesity are associated with a wide range of serious health consequences, including:
- Cardiovascular Diseases
- Increased risk of hypertension (high blood pressure)
- Elevated risk of heart disease, including coronary artery disease, heart attacks, and strokes
- Higher likelihood of developing atherosclerosis (hardening of the arteries)
- Type 2 Diabetes
- Overweight and obesity are leading risk factors for the development of type 2 diabetes
- Excess fat, particularly abdominal fat, contributes to insulin resistance, leading to higher blood glucose levels
- Respiratory Issues
- Obesity can lead to conditions such as sleep apnea, where breathing repeatedly stops and starts during sleep
- It may also cause asthma or worsen existing asthma symptoms
- Musculoskeletal Disorders
- Excess weight puts strain on joints, leading to conditions such as osteoarthritis, particularly in weight-bearing joints like the knees and hips
- Increased risk of back pain and other musculoskeletal problems
- Cancer
- Obesity is linked to an increased risk of several cancers, including breast, colon, endometrial, kidney, and pancreatic cancer
- The exact mechanism isn't fully understood, but factors like chronic inflammation, insulin resistance, and hormonal imbalances may play a role
- Mental Health
- Obesity can lead to psychological issues such as depression, anxiety, and low self-esteem due to societal stigma and body image concerns
- There may also be an increased risk of eating disorders
- Reproductive Health
- Obesity can affect fertility in both men and women, leading to conditions such as polycystic ovary syndrome (PCOS) in women
- It can also increase the risk of complications during pregnancy, such as gestational diabetes, preeclampsia, and the need for cesarean delivery
- Liver Disease
- Non-alcoholic fatty liver disease (NAFLD) is commonly associated with obesity and can progress to more severe liver conditions like non-alcoholic steatohepatitis (NASH), cirrhosis, and liver cancer
- Digestive Issues
- Obesity increases the risk of developing gastroesophageal reflux disease (GERD) and gallbladder disease
- Reduced Quality of Life
- Obesity can lead to physical limitations, decreased mobility, and lower overall quality of life
- It may also contribute to social isolation and difficulties in professional life due to discrimination or physical limitations
