Being underweight is defined as having a body mass index (BMI) below 18.5. This is estimated to be less than the body mass needed to sustain optimal health.

Some people are naturally very skinny but still healthy. Being Underweight according to this scale does not necessarily mean that you have a health problem.

Being underweight is about 2-3 times as common among girls and women. In the US, 1% of men and 2.4% of women 20 years and older are underweight 

What Are The Health Consequences Of Being Underweight?

Obesity Is currently one of the world’s biggest health problems. However, being underweight may be just as bad for your health as being obese. According to one study, being underweight was associated with a 140% greater risk of early death in men, and 100% in women. Another study found increased risk of early death in underweight men, but not women.

This indicates that being underweight may be worse for men. Being underweight can also impair immune function, raise your risk of infections, lead to osteoporosis and fractures, and cause fertility problems.