As others have said, if you want to grow, you need to eat big. However, I don't recommend just going all out and eating everything in sight. That can get out of hand and leave you with a lot of excess fat. I suggest a more methodical approach. Note I have posted this same advice before, but this question keeps getting asked on here, so my advice remains the same:
Most skinny guys who say they eat "a lot" actually eat very little when they calculate it out. Go to this website here:
Fitday
and enter in a typical day's diet to see exactly how much you have been eating. I know guys who need to eat 7k+ cals/day to gain weight. You may have a fast metabolism, but that is no excuse. Trust me, you CAN outeat it.
Once you have a rough figure for what you are eating in a day, estimate your maintenance calories here:
BMR calculator
Your "maintenance calories" refers to the number of calories needed to exactly maintain your weight.
Make sure to click on the link labeled "Daily caloric needs" to get your actual number of calories per day.
Now, once you have this number, eat that amount of calories every day for a week. Track your weight first thing each morning. If you have not gained a pound by the end of the week, then add 300 cals to your daily total and eat that much for the next week. Repeat this process until you are gaining ~1 lb./week.
I would advice you get 40% of your calories from protein, 40% from carbs, and 20% from healthy fats. Some people use other amounts but for a beginner it should work fine.
Need advice on what exactly you should be eating? Try here:
What to eat
The absolute cheapest source of protein right now is canned chunk lite tuna. Whey protein is good, although the price has skyrocketed over the past few months. ON 100% Whey is the 2nd cheapest source of protein right now, if you buy from here:
link
The cheapest source of carbs would be quick oats.
For fats, you can get a bottle of generic olive oil for pretty cheap.
This stuff may not be very appetizing, but if you want to gain weight for the least amount of money, you may have to sacrifice some taste.
I trust you have a solid weightlifing program in place. Without a good routine, you will not gain the type of weight you would like.
Finally, check out the link in my sig. Read the stickies posted in the various forums, and feel free to register and ask questions. The members there are very helpful and knowledgable.
Good luck, and feel free to PM me with questions. I get tired of typing all of this out because it gets asked on AT at least once a week.
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