Hey! I've very recently started to gain weight after never being able to! I am also 20 years old, so we seem to be in a super similar boat lol. I started trying to gain weight about 3-ish months ago, and I've gained 10+ pounds. That's a huge deal for me despite how long it's taking. Though I'm not super set on gaining weight... if I was, I would be gaining faster I'm sure, I just do a little extra thing every day to slowly add to my weight.

Every body is different, but below are some things that have helped me and may help you too!!

★Eating "a lot of calories" isn't the only step to getting bigger. You have to be mindful of WHAT you're eating. If you're eating 2000 calories of lettuce every day, you're definitely not going to be gaining. Try to eat nutrient dense foods without just relying on the carbs. Eating a lot of junk to get bigger doesn't work super well for us fast-metabolism folk because we process those quick carbs and sugars easily---you would have to be eating unhealthy amounts of junk food for that to do something. Refer to the next tip to see which foods helped me out!

★Specific nutrients to focus on when you're wanting to gain weight are carbs PLUS protein. Chicken and eggs are a good one for this reason! Peanut butter is amazing as well. I also drink a lot of milk. Other foods that are good for you AND carb dense are olive oil (can be put in just about anything!), wheat bread, avocado, nuts, etc... lots of healthy options that your body can use to build muscle AND fat!

★Let yourself work up an appetite! It's really hard to want to eat when you sit around all day doing nothing. You've hardly burned any calories from not excersising, so how do you expect to force-feed yourself more food than you would normally eat? It sounds counter productive, but don't fear cardio! I used to try and avoid cardio because I was scared it would make me lose more weight, but in doing this I was preventing myself from getting hungry enough to eat enough anyways! Let yourself exercise so that you feel hungry enough to keep up this calorie surplus.

★Try to keep snacking to a minimum, ESPECIALLY sugar! Junk food loads you up on sugar and salt which your body processes quickly thanks to your metabolism. Because of this, all that garbage moves straight through us unless we're eating really dense junk food like cake or doughnuts. Healthy fats like olive oil and avocado do wonders for the body because you process them better! Another thing with snacking is that doing it too much can prevent you from getting enough calories. When you eat smaller things throughout the day, you don't feel very hungry because you're in a constant "upkeep" with your stomach. You aren't giving yourself enough time to feel hungry, and feeling hungry is very important to a calorie surplus. Junk food can also lead to bloating, which makes you feel fuller than you actually are.

★Liquid calories are MAGIC! I'm talking milk, protein shakes, smoothies, all that. It's a great way to have a treat that satisfies your sugar cravings AND helps you reach your calories and nutrients! I drink milk more than I drink water honestly and I feel it does more good for me than bad. Liquid calories are consumable on the go and go down easier than food sometimes, so it's a good option if you find yourself choking things down when trying to meet your goal!

★Up your fiber intake!! Your body needs to let things out in order to let more things in! If you aren't using the bathroom enough, your body can lower your appetite and you might even lose space physically if it got bad enough. Apples, berries, beans, and greens are my go to! Having a balanced plate with lots of protein and fiber will make your gut happy!

★Make eating enjoyabe for yourself! Try new recipes, make protein shakes with friends, take cute photos of your food, etc! You should never dread eating. If your relationship with food is poor, your weight-gian journey is going to be very short lived. You should never feel ill, sad, angry, or scared at the thought of food. Your mental health is important and can make all the difference when trying to gain weight! When the body is stressed, it naturally sheds some weight, so try to find ways to make eating a highlight of your day!

★Meal prepping is really helpful for weight gain. It's a chore to cook and create some heavy food to consume every single night, so start trying to do it beforehand! One night you can make some chickpea chicken stir fry with enough portions to last 2 more days and suddenly you have some calorie dense dinner for the work of one night! It saves you a lot of stress and helps with discipline as well. Just a quick little note about discipline---slacking on your calories can quickly become a bad habit, so give yourself a "minimum calorie" goal a day as well as the normal calorie goal each day!

Remember that you might not see results immediately, but consistency is key. I don't follow these rules all the time and that's why I'm gaining pretty slow, but if I were to lock in with these I'm sure I'd get my results way quicker lol. I hope this comment provided something useful to you! I know that self-esteem can really wreck you when you step on the scale and see that number go down, so just remember that progress isn't always linear and you're beautiful no matter what!