For your age and height, you should consume daily between 2300-2600 calories daily which should be spread throughout the day in 3 meals and snacks between meals. From your statement it was not clear what you changed in your diet. You are approximately 25lbs underweight for your height. Since you are underweight, suggest gaining weight slowly, try to eat a Heart Healthy diet which will give you the nutrients, vitamins and minerals your body needs, and help with possibly preventing future disease states. Heart Healthy diet which is a moderate fat diet and a moderate fat diet means = using polyunsaturated (omega 3, corn oil, nuts, etc) fats and monounsaturated (olive oil, canola oil, peanut oil, etc) fats, no saturated fats (high fat snack foods, butter, fat spreads) and no trans fats. Eat low fat meats (chicken, fish, loin of pork) or non-meat sources (soy products, nuts), low fat vegetarian combinations (rice & beans, pasta & beans, low fat cheese & pasta), low fat and substitute dairy products (1% milk, low fat/fat free yogurts, low fat soy milk/soy yogurt), use plant oils, non trans-fat margarines, and eat a lot of fruits and vegetables. Eat daily high fiber breads and cereals (oatmeal). Try nutrient dense drinks 1-2 a day, either purchase them, such as Ensure or Boost, or make your own milkshakes - milk, ice cream, and frozen fruit blended together or yogurt smoothies - yogurt, milk, and frozen fruit blended together for additional calories, protein and nutrients to help increase your weight. Hoped that helped you.
Things I forgot to mention: I have very low LDL cholesterol (even though I shouldn't, I like to eat a lot of fat), and the CBC revealed a very normal and very healthy results. Vitamin screen also revealed normal results.