Eating Right for Dummies (Advanced Version)

*Please read the basic and intermediate versions prior to this post.
**Consult your doctor before beginning any diet or exercise program.

Firstly, I just want to clarify/restate that the complexity of your diet program should serve the purpose you want to use it for.  For example, you may be content to follow the basic version and that is just fine.  When deciding whether you want a "basic" or "advanced" diet, consider the following options
1)  More aggressive goals decrease the likelihood of sticking with your diet
2)  Your physique will reflect the effort you put into your dieting
3)  Sedentary lifestyles will require a more strict diet to maintain similar physiques
4)  Active lifestyles will not need to follow as strict of diet to "stay in shape"
Lets take a look at each of those.
1)  The "basic version" will by far be the easiest to follow, however, the "advanced version" will lead to the best control over your body and lead to the best results
2)  If you just want to "live healthier" then maybe the Basic Version is for you.  If you want to look like you belong on a magazine cover then you need to put in the effort that yields what you want your body to look like.  If  you half-ass your diet, expect your body to look like such.  If you spend hours researching, calculating, measuring, diligently following diets and workout regimes... then the same is also true.
3)  When I was in school, in spite of working out almost daily, I had a very sedentary lifestyle.  When I was not working out I was either sitting in class, behind a computer, or doing homework at a desk.  This meant my diet had to be VERY precise in order to maintain the physique I wanted.
4)  Since starting training MMA, I spend about 3 hrs per day doing high intensity workouts that are very aerobic and anaerobically strenuous activity opposed to one set (lasting maybe 5 sec) then resting for 5 min.  I essentially burn off any food I put into my body and do not NEED (though for optimal performance should) as strict of a diet to maintain my physique.

With those things in mind.  Lets continue with the meat and potatoes of the Advanced Version:
     Caloric Intake - This is going to be the baseline for the entire diet.  I usually recommend to people that before beginning a diet they should monitor how many calories they eat per day for an entire week.  You only need to count calories for this period.  Keep track of everything you eat throughout the day and either at the end, or when you have the wrapper handy, jot down the calories contained in each thing you eat.  Many restaurants now how have this information available online if you eat out a lot.  The measuring makes sure that the diet is personalized for your body weight and natural caloric needs (and metabolism).  The reason I recommend doing this for a week is that there are many factors that may contribute to one "out of the ordinary" day where you either eat much more or much less than you normally would.  During this trial period DO NOT eat any more healthy or unhealthy than you normally would.   Just go about your normal diet and exercise habits, the only things that should change is that now you're documenting it.  Once your trial week is up, add up all the daily caloric totals and divide by 7 to get the mean (average) of your daily caloric intake.
     Prudence - As stated earlier, it is not healthy to either loose or gain more than two pounds per week.  Any fad diet you see advertising more is likely a hoax referring to TEMPORARY dehydration.  However, it should be mentioned that the more you weight, the easier it is for you to loose any given amount because it is a smaller percentage of your total mass (20 lbs is only 10% of a 200lb man vs. 15% of a 130lb woman).  Also, the more fat you are, the easier it will be to loose excess fat for the same reason (its easier for someone with 20% body fat to loose 5% than it is for someone wanting to go from 15% down to 10% body fat).  As I mentioned before it is the cold hard truth that the more weight you expect to loose, and the shorter the period of time you expect to loose it, the more likely you will fail at your diet and gain all the weight back.  Your goals should be challenging yet reasonable.
     Reducing Intake - Lets say (for example) you consume an average of 2,000 calories  per day.  Consider the following example:  (I chose this example for the purpose of simple math, I DO NOT recommend it, DO NOT follow this example because if you cut your caloric intake in HALF (2,000 to 1,000) for 5 weeks you will likely suffer from a major case of DEADNESS!).  If you want to 10 lbs in 5 weeks that means that you will need a total caloric deficit of 35,000 calories (3,500/lb).  35,000 / 5 = 7,000 caloric deficit per week; 1,000/day.  Instead of eating 2,000 calories per day you would only eat 1,000.  More realistically lets say that you wanted to loose 5 lbs in 1 month (4 weeks).  (This example is still pretty aggressive considering you are still dropping a large percent of your daily intake.  625/2,000 is a daily deficit of over 30%... refer to "Prudence").That's a total caloric deficit of 17,500 calories (3,500 for each lb you want to loose).  17,500cal / 4 weeks = 4,375cal.  4,375cal / 7days = 625 calories / day.  If you currently consume 2,000 calories per day and drop to eating only 1,375 calories per day (a daily deficit of 625 calories) and stuck to that for 4 weeks (28 days) then you would loose about 5 lbs.  Got it?
     Macro Nutrient Ratios - When trying to build muscle, I like a macro nutrient ratio of:  50% carbohydrates, 30% protein, and 20% fat.  When trying to loose fat, I like a ratio of:  30% carbohydrates, 40% protein, and 30% fat.  Using the example above (again this is JUST an example, by no means a recommendation) of 1,375 cal / day:  40% of 1375 is 550 and 30% is 412.5.  This means that your total daily caloric intake should be 1,375 with 550 (40%) coming from protein, 412.5 (30%) from carbohydrates and fat each.  This means that following a macronutrient ratio of 40/30/30 (P/C/F) you would want to consume 137.5g of protein (137.5g x 4cal/g = 550cal), 103.125g carbs (103.125 x 4cal/g = 412.5cal), and 45.8333g fat (45.8333g x 9cal/g = 412.497cal).  OF COURSE you DO NOT have to follow these kinds of things to halves of grams or less, that is just ridiculous.  Rounding to the nearest whole gram is PLENTY accurate.  Do not sweat the small stuff, if your total calories is over by an amount you deem to be negligible then so be it.  Again, refer to Prudence.  The more accurate the better, but you also need to be able to maintain your plan.
     Meal Times and Composition - All the "rules" stated in other posts are still in play.  You should eat every 2 - 3 hrs or 5 -7 meals per day.  You should eat a balanced amount of fat every meal with a bit less at the last meal of the day.  You should eat a balanced amount of protein at ever meal with slightly  more after your workout and at your last meal.  Your carbs should spike at your first meal and your post-workout meal.  As always, don't forget your fruits and veggies as well as good fat sources like fish and nuts.    

     Variety - This is very important.  In order to maintain this type of program you are likely going to find yourself eating many of the same foods over and over and over again every single day.  This can get very redundant.  The key is to find similar foods of similar nutrient ratios.  For example, if you want to substitute ground beef for chicken that is fine, but be conscious that beef has a higher fat content than chicken and remember to adjust the rest of your meals accordingly.  Many green vegetables will have the same nutrient ratios as long as you avoid starchy veggies like sweet corn and potatoes.  Again, these are fine as long as you adjust your daily intake accordingly. 

     That is it!  The complete Eating Right for Dummies!  Your diet should fit your lifestyle goals.  The ONLY time I would actually use the Advanced Version myself would be (as exemplified earlier in this post) if I were living a very sedentary lifestyle.  The more active you are, the less precise your diet needs to be, HOWEVER, in order to obtain maximum performance from your body and and maximum health consciousness in your brain; you should try to follow a diet plan that is a compromise that suits your needs.  Preliminary guidelines are likely not going to be enough to "whip you into shape" and for sure will not land you on the cover of Men's Health.  Likewise, If you try to follow the above Advanced Diet you are likely to burn out because you will be eating a lot of the same old things every day.  For the every day person I do not really recommend this diet and only recommend it for the most intense dieters; the balance is that knowledge is good... period.