I am under weight.
90 pounds at 5'3.
Any tips?
*I'm not anorexic, it's genetic.
Im a Female Btw, almost 18.
I can help. However, I would prefer to take this to private messaging as I could quickly high-jack this thread.
I'm a bodybuilder. I maintain less than 10% BF year round and I'm telling you, the secrets to weight gain for ectomorphs (what you are) is hard to find on the internet. A good 50-70% of all people are endomorphic, which means they hold weight and gain weight easily, especially fat. So their advice will differ greatly from the unconventional, uncommon advice you need to hear about gaining weight.
It takes time and thought really. Not all foods breakdown the same in the body, and some are prone to leaving you full while others are prone to leaving you very hungry.
As a start, here is some basic direction.
Avoid saturated fats - they take too long to breakdown in the gut and leave you full for longer periods of time. Even worse, your body uses very little energy to digest them too, paradoxically. This means less energy burned, more stored as fat and a full stomach.
Eat lots of complex carbs and a moderate amount of protein. A good ratio to shoot for is for every 1g of carb you eat, have .5g of protein with it.
So if you eat 50g carbs, have 25g protein in the mix. The fats will come if you just focus on these two. Smaller meals throughout the day is sound advice. You don't have to get crazy at first, just 4-5 meals a day to start. From there, as you implement training, you can start increasing consumption at each meal, then the meal frequency. Eventually, you'll be eating ALOT more and you'll also be increasing your metabolism. So likely, because you are an ecto, you'll pack on relatively lean weight.
Before you go any further, go ahead and thank Jesus for giving you an ectomorphic body, as most people even on this board would gladly take over their own.
We can get into science later. I have to see how this board responds to my advice, first.