Lack of weight, now that is something we rarely hear of in our world of obese people. Still, being too thin can be a problem, and it does not have to be related to dying from starvation. Think of our body as a building. If its walls and floors are thinner than they should be, there will be problems. Did you know that would-be blood donors are refused if they are under certain weight? That said, being too thin can cause (if you are a female) your menstrual cycle to come to a halt (this may sound good - no more bleeding, but it is the sign of a serious breakdown in you organism). Or, you might be just the right weight, but you are a sportsman and you need to be over a certain weight limit to be allowed to compete. Whatever your cause, here are some tips how to gain weight.General directives
When you consume more calories than you burn, you gain weight. Consume more caloric food, but remember to choose healthy food. Also, eat more frequently. A good idea would be to have three regular meals and three meals between them, and when you eat little portions frequently, you digest food better, meaning that more of it is adequately used. Best solution is to go for healthy foods that are high in proteins and calories and contain sufficient amounts of complex carbohydrates and healthy fats.
Let us just remind you of one thing before you go and lay available food supplies to waste. You are trying to gain weight, not to gain fat. Too much fat is too much fat, regardless of whether it sticks to a thin or a regular-sized body frame. That is why you should avoid junk food and opt for healthy foods. Also, exercise. You will be gaining muscle, and muscles are heavier than fat for equal amounts of volume. This means that you will be heavier, but still able to fit in your old clothes.
Exercise, combined with increased calcium input (milk and dairy products are rich with calcium), will help to build stronger, sturdier bones, which are also heavier.
Key to growing bigger muscles is sufficient intake of protein. Go for lean meats, eggs, milk, and low fat dairy products, nuts and beans. These foods are all high in protein. However, do not take protein supplements; these are for people who know the why's and what's. Get a professional advice on these. Also, remember that your body requires good kinds of fat, as those found in cold pressed olive and sunflower oil and complex carbohydrates (fruits and honey are good, sugar is not).