Brief Answer:
Diet changes will help more than protein supplements.

Detailed Answer:
Hello,
Thanks for posting your query.
Being lean and thin can be due to many causes and finding out the main cause will help in gaining the weight. Genetics is the main factor responsible. If your parents or siblings are also underweight then may be it is in your genes. The causes that need to be ruled out are -
1. Depression.
2. Addison's disease- A hormonal problem- Some simple blood tests will rule this out.
3. Chronic illness-A long standing viral illness also causes lack of a healthy look.
4. GERD- I hope you do not have any pain abdomen, loose stools, burning sensation in upper abdomen, etc.
5. Viral gastroenteritis.
6. Stress and anxiety.
7. Malnutrition.
8. Intestinal worms.
9. Thyroid disorders.
All these causes need to be ruled out with the help of your physician after a thorough examination and some blood tests.
The primary rule is to increase the calorie intake and do some form of exercise along with it. Taking the protein drink after exercise will not help you much.
Some measures:
1)Start your day with a healthy breakfast comprising a glass of milk and a banana or a banana milkshake.
2)Have frequent small meals every three hours in a day and divide them into six small meals comprising of proteins in one meal as pulses,cereals,beans,legumes, etc.
3)Have energy dense foods as dry fruits, nuts, seeds when you snack.
4)If you take non veg have fish,chicken with pulses rice thrice in a week.
5)Avoid junk food intake as it has empty calories.
6)Make an exercise plan and do some form of muscle building exercises. It will be best if you do under guidance of a trainer so that he can analyze and observe for changes. Exercises like squats, chin-ups and bench press help in weight gain.
7)Avoid smoking, alcohol if you are using them regularly.
8)Drink lots of water.
You can consult a Nutritionist who can guide you according to your cuisines and then keep tracking for changes.
There is no substitute of eating a healthy diet for gaining weight.

I hope this answers your query.
In case you have additional questions or doubts, you can forward them to me, and I shall be glad to help you out.
Wishing you good health.
Regards.
Dr. Praveen Tayal.
For future query, you can directly approach me through my profile URL http://bit.ly/Dr-Praveen-Tayal

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Brief Answer:
It is not unhealthy.

Detailed Answer:
Hello.
Thanks for writing again.
It is not unhealthy to have the protein powder GNC but you can have better results if you combine it with the dietary changes I have suggested. You can try taking it with a regular exercise.
Hope my answer is helpful.
Do accept my answer in case there are no further queries.
Regards.

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