Hello dear..I have gone through your post in which you have asked about Nutrigain.
Nutrigain is a product made of certain herbs which are helpful for gaining weight.
But these products are only dietary supplements & should not compromise on routine healthy food such as:
Consume more of natural diet like fresh fruits, green vegetables, milk, eggs, wheat, etc.
Avoid oily and junk food.
Stay away from smoking & alcohol.
Best is to stay active, exercise regularly, avoid stress, get good sleep, think positive and stay happy.
Wish you a healthy life.
Take care.