What is classified as underweight?

Being classified as underweight refers to the condition where an individual's weight is lower than what is considered healthy for their height. This classification typically comes from the Body Mass Index (BMI) scale or similar metric that assesses weight in relation to height. The BMI is calculated using a person's weight and height to categorize them as underweight, normal weight, overweight, or obese.

When someone falls below the standard weight range for their height, it can indicate potential health risks, including malnutrition, weakened immune function, and increased vulnerability to certain diseases. This classification serves as a signal that an individual may require nutritional assessment or intervention to reach a healthier weight.

The other choices do not accurately describe the underweight category. Being above the standard weight range indicates overweight or obesity, having an excessively low body fat percentage may point to extreme leanness but does not specifically define underweight status, and maintaining an ideal weight range signifies a healthy state rather than underweight.