5 doctors weighed in:
How can I gain weight? I am very thin with weight of 45kg and tall 159cm
5 doctors weighed in

Dr. Robert Purchase
Orthopedic Surgery
3 doctors agree
In brief: Resistance exercise
It is not advisable to simply add fat in order to gain weight.
While you do sound of slight build, your body probably fits your build. If you do want to add weight, focus on lean body mass. The only way to build lean body mass (ie muscle) is with resistance exercises, ie lifting weights. Simply increasing your caloric intake to exceed your daily need will only add fat.

In brief: Resistance exercise
It is not advisable to simply add fat in order to gain weight.
While you do sound of slight build, your body probably fits your build. If you do want to add weight, focus on lean body mass. The only way to build lean body mass (ie muscle) is with resistance exercises, ie lifting weights. Simply increasing your caloric intake to exceed your daily need will only add fat.
Dr. Robert Purchase
Dr. Robert Purchase
Thank
Holly Barth
General Practice
In brief: Diet & lift weights
To gain weight you have to consume more calories than you are burning.
Do this in a healthy way though. Don't choose junk or fast food. Keep a well balanced diet and make sure you are getting all the nutrients you need. Don't cut out exercise as it is very good for you. Weight lifting and other muscle building exercises can help you increase your body mass.

In brief: Diet & lift weights
To gain weight you have to consume more calories than you are burning.
Do this in a healthy way though. Don't choose junk or fast food. Keep a well balanced diet and make sure you are getting all the nutrients you need. Don't cut out exercise as it is very good for you. Weight lifting and other muscle building exercises can help you increase your body mass.
Holly Barth
Holly Barth
Answer assisted by Holly Barth, Medical Student
Thank
Get help from a real doctor now
Dr. Warren Strudwick
Board Certified, Sports Medicine
26 years in practice
490K people helped
Continue
107,000 doctors available
Read more answers from doctors