I got this from bodybuilding.com, written by Emma. She really knows her stuff.

Not sure if Im allowed to post this, since it doenst belong to me, if so delete this, but this seriously changed my way of seeing diets..

I think this is a must..

Quote Originally Posted by Emma-Leigh View Post
Thought I would write up a quick run down of calories and Macro's for everyone.


Calculating Calories and Macro's

Basic Terminology
1/ BMR (Basal metabolic rate): This is the amount of calories you need to consume to maintain your body if you were comatose (base level)....
2/ NEAT (Non-Exercise Associated Thermogenesis): The calorie requirements added by your daily activity that is NOT exercise (eg: washing, walking, talking, shopping, working). This is generally the most marked variable in a persons daily calorie requirements and something that everyone has a good amount of control over. This is what people term INCIDENTAL EXERCISE. It is also what helps keep 'constitutionally lean' people LEAN (they fidget)!
3/ EAT (Exercise Associated Thermogenesis): The calorie requirements associated with planned exercise.... Unless someone is doing a whole heap of exercise (eg: two or more hrs training a day) it usually doesn't add a stack of calories to your requirements (30 minutes of 'elliptical training isn't going to do it')
4/ TEF (Thermogenic effect of feedng): The calorie expenditure associated with eating.... REGARDLESS of what myths you have been told - this is NOT dependent on MEAL FREQUENCY. It is a % of TOTAL CALORIES CONSUMED (and 15% of 3 x 600 cal meals is the same as 15% of 6 x 300 cal meals). It varies according to MACRONUTRIENT content and FIBER content... For most mixed diets, it is something around 15%.... Protein is higher (up to 25%), carbs are variable (between 5-25%), and fats are low (usually less than 5%). So ->> More protein and more carbs and more fiber = HIGHER TEF. More FAT = LOWER TEF.
5/ TEE (Total Energy Expenditure): The total calories you require - and the sum of the above (BMR + NEAT + EAT + TEF).


How much do you need?
So - as indicated by the above information, there is therefore a multitude of things that impact a persons MAINTENANCE calorie requirements....
- age and sex (males generally need > females for any given age)
- Total weight and lean mass (more lean mass = more needed)
- physiological status (eg: sick or injured, pregnant, growth and 'enhancement')
- hormones (eg: thyroid hormone levels, growth hormone levels)
- exercise level (more activity = more needed)
- daily activity level (more activity = more needed)
- Diet (that is - macronutrient intake)

In order to calculate your requirements the most accurate measure would be via Calorimetry [the measure of 'chemical reactions' in your body and the heat produced by these reactions]. This can be measured directly (via placing you into a calorimeter where the heat you produce is measured) or indirectly (eg: HOOD studies where they monitor how much oxygen you use/ carbon dioxide and nitrogen you excrete over a given time). Although accurate - this is completely impractical for most people... So we mostly rely on pre-set formula to try to calculate our needs.


Estimating Requirements
The simplest method of estimating needs is to base your intake on a standard 'calories per unit of weight (usually kilograms)'. Typically this is:
- 25 to 30 kcals/kg/day for normal, healthy individuals with sedentary lifestyles doing little physical activity [11.5-13.5 kcal/pound]
- 30 to 35 kcal/kg/day for those involved in light to moderate activity 3-5 x a week with moderately active lifestyles [13.5-16 kcal/ pound]
- 35 to 40 kcals/kg/day for those involved in vigorous activity and highly active jobs [16-18 kcal/ pound].

There are then a number of more complex formula which calculate BMR based on any number of variables including sex, height, weight, age, and lean mass. This BMR is then multiplied by an 'activity variable' to give TEE. To go over a few BMR calculations:
1/ Harris-Benedict formula:
For MEN: BMR = 66 + [13.7 x weight (kg)] + [5 x height (cm)] - [6.76 x age (years)]
For WOMEN: BMR = 655 + [9.6 x weight (kg)] + [1.8 x height (cm)] - [4.7 x age (years)]
This formula is particularly inaccurate - It was derived from studies on LEAN, YOUNG, ACTIVE males in a COLD lab MANY YEARS AGO (1919) and is notorious for OVERESTIMATING calorie requirements, especially in those that are overweight. IF YOU WANT AN ACCURATE READING, DON'T USE IT!

2/Mifflin-St Jeor:
For MEN: BMR = [9.99 x weight (kg)] + [6.25 x height (cm)] - [4.92 x age (years)] + 5
For WOMEN: BMR = [9.99 x weight (kg)] + [6.25 x height (cm)] - [4.92 x age (years)] -161
This formula was developed in the 1990s. It is much more accurate than the above as it is more realistic in todays lifestyle settings.... However, it still does not take into consideration the difference in metabolic rate as a consequence of high BF%. Thus, once again, it also overestimates needs in highly obese individuals. So - once again, if you use it, be warned it can OVERESTIMATE your needs.

3/Katch-McArdle:
BMR = 370 + (21.6 x LBM)
Where LBM = [total weight (kg) x (100 - bodyfat %)]/100
This is considered the most accurate formula for those who are relatively lean and who have a good understanding of their bodyfat %.

To then convert to a TEE you multiply the BMR from the above equations by an Activity Factor
1.2 = Sedentary (Little or no exercise and desk job)
1.3-1.4 = Lightly Active (Light exercise or sports 1-3 days a week)
1.5-1.6 = Moderately Active (Moderate exercise or sports 3-5 days a week)
1.7-1.8 = Very Active (Hard exercise or sports 6-7 days a week)
1.9-2.0 = Extremely Active (Hard daily exercise or sports and physical job)
(note: these activity factors generally include a TEF of ~ 15% - which is an average mixed diet).


Just How Accurate are they?
Unfortunately, many people rely on these generic 'online calculations' to calculate how many calories they need... And although they can (sometimes) give rough ball-park figures, they are rarely accurate. Most people OVERESTIMATE their activity factor, and UNDERESTIMATE their bodyfat - and end up eating TOO MUCH. So - you are better off starting with these 'rough figures' and then monitoring your weight/ measurements for 2-4 weeks. IF your weight is stable/ measurements are stable, then you have likely found your maintenance intake.


Using the Above to Recalculate Based on Goals
Taking the above, you will then need to DECREASE or INCREASE intake based on your goals of INCREASING mass or DECREASING mass. For this - instead of using 'generic calorie amounts' (eg: 500 cals/ day to lose weight) I would recommend starting with adding/ subtracting based on a % of your maintenance - reason being is that the effect of a given calorie amount on an individual is going to be markedly different based on their size/ total calorie intake.... For example - subtracting 500 cals/ day from a 115# females 1500 total intake is 1/3rd of her total cals but 500 cals/ day for a 215# male on 3500 total intake is only 1/6th of their total... And it will result in markedly different effects on their energy levels and weight loss.

Generally speaking:
-> to ADD weight: ADD 10-20% calories to your total from above
-> to LOSE weight: SUBTRACT 10-20% calories from your total from above
Then monitor your results and adjust as required.


Macronutrient Needs
Right... Once you work out how many CALORIES you need to reach your goals - > And this should NOT be based on a generic RATIO of total calorie intake such as '30:40:30 or 40:40:20. Your body doesn't CARE what % intake you have for macronutrients. It works in terms of QUANTITY and therefore your level should relate back to your BODY and your bodies NEEDS in terms of LEAN MASS and ACTIVITY!!!

1. Protein: Although most accurately based on LEAN MASS it is easiest just to set up a general starting point:
Protein (grams) = 1-1.5 x total weight (pounds).
If you are VERY LEAN or very LOW IN TOTAL CALORIE INTAKE then you need to stick to close to, or increase ABOVE, 1.5 x weight.... (eg: 2 x LEAN MASS)
If you are VERY OVERWEIGHT or VERY HIGH IN TOTAL CALORIE INTAKE then you should stick closer to, or decrease slightly BELOW 1 x weight (eg: 1 x LEAN MASS)...

2. Fats: Generally speaking, although the body can get away with short periods of very low fat, in the long run your body NEEDS fat to maintain general health, satiety, and sanity.... If you are following a 'normal distribution' of intake you should be aiming for something between 0.35-0.5 x LEAN MASS POUNDS (if highly overweight) or 0.35-0.5 x TOTAL WEIGHT POUNDS (if lean).
Note 1: Total fat intake is NOT the same as 'essential fats' (essential fats are specific TYPES of fats that are INCLUDED in your total fat intake)...
Note 2: For those who are on LOW carb diets, or those who have SPECIAL NEEDS - fat intakes CAN BE HIGHER with values up to 1 x total weight often used.

3. Carbs: Although carbs help with workout intensity, health, and satiety (and sanity) with no specific 'requirements' for your body, carbs are basically used by most as 'the extra stuff' that fills in the rest of your calorie requirements once the above two factors are considered. Obviously if your HIGHLY ACTIVE or trying to GAIN MASS then you will likely need MORE carbs to fuel your workouts and your body. If you are NOT active or if you are DIETING - then you obviously don't need / can't eat as much....
So to calculate your carbs you simply do this: [Total calories - ([protein grams as above x 4] + [fat grams as above x 9])]/4


How do I count Calories accurately?
Check out This thread here - Calorie Counting Websites

What are Macronutrients and Micronutrients?
Check out Macro and micronutrients explained!

Want a handy spreadsheet to do all the work for you?
Check out *Total Metabolism Forecaster Thread*