Eat Frequently
Go to long in between meals and your body's endocrine system will go out of control. When this happens your body goes into starvation mode, lowers hormone levels (insulin) slowing down your metabolism so you burn fewer calories and burn muscle. Then when you do eat (generally a big meal because your real hungry) your body will raise those hormone levels too high, once again lowering your metabolism, and you'll store too much of that food as body fat to prepare for the "famine" to come. That's why many times when your going too long between meals you'll tend to fell sluggish and even irritable (bodies chemical levels are too low) while after eating a big meal you'll also feel sluggish and tired (bodies chemical levels are too high). Eating frequently will allow you to maintain perfect hormone levels so your metabolism (ability to burn fat) will function at the highest possible rate.
Your body also needs regular amounts of protein throughout the day. The human body can only store so much protein and after about 3 hours will began to take these proteins (amino acids) from your muscles. To insure that you don't loose any valuable muscle, and your metabolism and energy levels are functioning at 100% efficiency, be sure to eat every 2-4 hours.
Eat Quality
Eating junk food every few hours won't do much for your body -- remember, you are what you eat. Try to eat as natural as possible: meats (soy is good if you are vegetarian), fruits, grains, vegetables, nuts, etc. A famous fitness guru once said, "If man made it, I won't eat it." If it's processed, then it's not as good for you.
Eat Balanced
If you're going to be really active in the next few hours eat more carbs, if not you don't need as many. Protein is necessary for building muscle and making your metabolism work properly. Eating protein 5-6 times a day is a lot easier for your body to digest than eating it all in one or two big meals. Protein and carbs have 4 calories per gram, but fat has 9 calories per gram and absorbs much easier into your body. If you're trying to lose weight, limit your fat intake to about 15-20% of your total calories. Eat mostly unsaturated fat (liquid at room temperature). For gaining weight, increase your fat intake to over 30%.
Eat the Right Amount
This one is the most obvious but the toughest to do. If you want to lose weight, you have to burn more calories than you consume. To gain weight, you have to consume more calories than you burn. To determine how many calories you burn each day, you need to know your Daily Caloric Intake.
Supplements
It is very hard, if not impossible to get all the nutrients you need from food alone. Even though many supplements promise more than they can deliver there are still many worthwhile reasons to invest in supplements:
-It is not always possible to eat 5-6 meals a day (meal replacement supplements)
-Do to the Pollution in the environment and processing of foods most foods lack the proper nutrients (vitamins and minerals plus herbs for cleansing).
-Your body is not always able to digest and process certain nutrients in the necessary amounts (amino acids, minerals and vitamins, protein).
- Periods of high stress require greater intake of certain nutrients (amino acids, minerals and vitamins, protein, herbs).
Water
The average person needs to drink 2 liters of water per day to stay properly hydrated. Drinking enough water is beneficial to your immune system, good for your skin, and increases your energy level. Extra fluid is needed in hot weather and when you exercise. For each hour of exercise, drink 1 liter of water, or enough to replace the fluids you've lost. These are the six core rules to idea nutrition. Follow them and watch your body make amazing progress.