Those of us who have fitness goals what to 
achieve something.  Whether it is gaining muscle, losing weight, 
or becoming better in the sport they play having a well structured diet 
is the key to improving in any of your goals!!
Why?
80% of whatever goal you have is reached 
through good nutrition.  Without a diet plan it will be very difficult, 
if not impossible to reach your goals. Your body needs fuel to function 
in everyday day life and food is that fuel.  If your putting the wrong 
kind into your body, then your body is going to be what you eat.
Basics of Weight loss
An easy way to break it down is knowing that
 it takes a cut of 3500 calories from your diet to lose 1 pound of fat. 
 Lets say for instance you are consuming 3000 calories a day you need to
 reduce you caloric intake down to 2650 which will result in a 1 pound 
loss in 10 days. That doesn’t mean you get to eat one pizza and now your
 daily limit is reached.  That is the complete opposite.  Calories in 
and Calories out.  This means you need to consume foods that are ready 
to be burned off through exercise rather quickly,  In weight loss, you 
would want to avoid foods that high in fats because well you want to 
lose fat.  Some fats though are beneficial as well because they carry 
the important vitamins your body needs.  Just remember that is a balance
 and keep your food intake in moderation.
Basics of Muscle Gain
There are great benefit to increasing muscle size for both men and women.
The more muscle you have on your body has the more energy (calories) is needed to function in everyday life. In essence it becomes easier to keep the fat off. Remember it’s not as simple as eating more calories. Sure you can get more calories from eating a cheeseburger but that doesn’t mean it’s helping you build muscle size. To gain a pound of muscle you need an increased caloric intake of about 2500 calories to your diet. If you’re eating 2750 a day then you need to increase that to 3000 a day to gain a pound of muscle in 10 days. This can be accomplished by finding your out how many calories you need based on your age, weight and activity level and then creating a meal plan that fits your goals.
The more muscle you have on your body has the more energy (calories) is needed to function in everyday life. In essence it becomes easier to keep the fat off. Remember it’s not as simple as eating more calories. Sure you can get more calories from eating a cheeseburger but that doesn’t mean it’s helping you build muscle size. To gain a pound of muscle you need an increased caloric intake of about 2500 calories to your diet. If you’re eating 2750 a day then you need to increase that to 3000 a day to gain a pound of muscle in 10 days. This can be accomplished by finding your out how many calories you need based on your age, weight and activity level and then creating a meal plan that fits your goals.
Tools
The best way of doing this is to track your 
caloric intake by using websites like the myfitnesspal and Calorie King 
apps for Android or iPhone will also help you track your calories. These
 tools will help keep you on track and achieve your goals more quickly 
than if you just guess how much you’re eating. While you do need to 
increase your caloric intake that doesn’t mean you can just eat whatever
 you want whenever. There has to be a balance of macronutrients and in 
appropriate portions.