BMI (Body Mass Index) is a measure of body fat based on height and weight that applies to adult men and women. It is calculated by dividing a person's weight in kilograms by the square of their height in meters.

While BMI is a useful screening tool, it doesn't directly measure body fat. It may not be accurate for athletes with high muscle mass, pregnant women, or the elderly. Always consult a healthcare professional for a comprehensive assessment.

For most adults, checking your BMI every 3-6 months is sufficient. However, if you're actively trying to lose or gain weight, you may want to monitor it more frequently.

Yes, BMI interpretation for children and teens (ages 2-20) is different from adults. It considers age and sex because body fat changes with age and differs between boys and girls.

BMI doesn't distinguish between muscle and fat, so it may overestimate body fat in athletes and underestimate it in older adults who have lost muscle mass. It also doesn't account for fat distribution, which affects health risks.