I recommend that your son be evaluated by his doctor
. Pectus excavatum, or "hollow chest," is a very common minor deformity. Many people have it and, generally speaking, it does not cause any serious health problems. Occasionally, pectus excavatum can be a sign of an underlying connective tissue disorder, such as Marfan syndrome. Therefore, most people with pectus excavatum should have a complete physical examination by their regular primary care doctor
to make certain that there is no evidence of one of these underlying conditions.
I did just calculate your son's body mass index (BMI) using the weight and height you gave me. These numbers give a BMI of around 15, which is definitely significantly underweight. I would definitely recommend that he meet with his regular doctor to figure out if there is any serious cause for his being underweight.
Some young adults are underweight because of high levels of physical activity. Other times, being underweight can be a sign of an eating disorder
, such as anorexia, which can definitely occur in young men and in fact are often underdiagnosed in men. Sometimes, there can be a chronic medical condition, such as celiac disease or inflammatory bowel disease, causing the weight loss.
I would encourage you to encourage your son to set up a visit with his doctor!