... I decided to make my post here. I'm 16, 5'7 and only 123 pounds! I think the normal for my age should be around 144-146 (correct me if i'm wrong). The trouble is... I have trouble GAINING WEIGHT! I'm an ectomorph (I think that's what they call it). Can someone please give me tips on how to gain weight? I really don't know the first thing about calorie intake and all that good stuff, so if someone could help me with that too I would be forever in your debt.
It's not about anything aesthetic either. I just want to feel more healthy by gaining more weight! Please help me! Thanks.
You need calories. How many depends on your body. If 2500 doesn't work, try 3000. If 3000 doesn't work, try 3500. And so on, until you find something that does work. Eat at least 6 meals a day. As far as the macronutrient mix, you probably don't have to eat excessively clean, so I'm not going to pick this one apart... just make sure you're getting enough protein.
You also need a good mass building exercise routine. If you don't workout already, join a gym. It's important to put all those calories to good use.
As for supplements, start out with a multivitamin and some creatine, maybe some protein powder as well. All pretty cheap.
It's totally possible. You would probably want to lower your LDL cholesterol while increasing your HDL cholesterol.
To gain weight, you need to up your caloric intake by eating more of the (preferably low-fat) foods that help improve your cholesterol profile while providing adequate protein and other nutrients. For example,
(Soluble) Fiber -- good sources have 5 grams or more per serving (eg. oats, whole grains, fruit esp. apples/grapes/citrus, legumes).
Fruits and vegetables -- antioxidants.
Unsaturated fats (the good fats) -- Monounsaturated fats (eg. canola/olive oil, avocados, almonds, walnuts, peanut butter) lower LDL without lowering HDL. Polyunsaturated fats (eg. sesame/corn oils, nuts) lower LDL but also lower HDL.
Avoid/limit trans fatty acids, saturated fats -- eg. fried foods, processed baked goods like cookies/donuts/crackers, stick margarine (read the label on the package and avoid "partially hydrogenated" anything)
Reduce cholesterol from animal products by occasionally substituting for soy products.
As for exercise, aerobic exercise is really important for decreasing health risks associated with high cholesterol. You should also implement a weight training program to help increase your weight through the addition of muscle mass.
Try eating the higher-calorie/higher-nutrient foods from the food groups. Instead of fresh fruit, eat more dried fruit. Have an avocado too! Nuts and dried fruit are really great for packing in alot of nutrients in a small package.