Macro Nutrients
Macronutrient Calories Kilojoules
Protein 4 17
Fat 9 38
Carbohydrate 4 17
Alcohol 7 29
The Numbers Don't Always Add Up
If you check a food label you may find that the total calories listed doesn't always match the number you arrive at using the ratios above and doing the math yourself. The reason for the discrepancy may be that the figure for carbohydrates includes insoluble fiber, and the food manufacturer has accounted for this in their figure for calories.
Insoluble fiber passes through your body without being converted to a form that provides energy, or calories. Knowing this, the manufacturer may subtract the caloric value of the insoluble fiber (4 calories per gram) from the total calories figure. When they do this, the 4-9-4 method will give you a higher figure for total calories than the one you find on the food label.
You might think that you could subtract the figure for fiber from the figure for carbohydrates to correct the discrepancy. But the figure for fiber will likely include both soluble and insoluble fiber, and you'd only want to subtract the insoluble fiber. Unfortunately you have no way of knowing how much of the fiber is soluble, and how much is insoluble.
So, now that we have an understanding of how our macro nutrients work we can look at trying to find out the proper ratio, or split of them to consume for energy purposes. This is a generic daily view of how to eat your macronutients.
All splits below are Carbs-protien-fat
Low fat 60-25-15 moderate basic 50-30-20
The Zone diet 40-30-30
Low carb 25-40-35*ketogenic 10-45-45
*used by body builders often before shows to "get ripped" or cut
So there lots of choices of different types of diets you can eat or stylize your own eating habits around. I wouldn't recommend the ketogenic diet unless you really wanted to make eating a pain in the ass though :) There are pros and cons to all the diets above but the most popular for healthy eating would probably be the moderate split.
Next Topic, BMR / RMR
BMR and RMR are estimates of how many calories you would burn if you were to do nothing but rest for 24 hours. They represent the minimum amount of energy required to keep your body functioning, including your heart beating, lungs breathing, and body temperature normal.
BMR stands for Basal Metabolic Rate.
RMR stands for Resting Metabolic Rate.
As BMR and RMR only represent resting energy expenditure, an adjustment must bemade to reflect your activity level. This is done by multiplying your BMR or RMR by an activity factor (McArdle et al 1996). Note that the following activity factors also take into account The Thermic Effect of Food:
| Activity Factor | Category | Definition |
|---|---|---|
| 1.2 | Sedentary | Little or no exercise and desk job |
| 1.375 | Lightly Active | Light exercise or sports 1-3 days a week |
| 1.55 | Moderately Active | Moderate exercise or sports 3-5 days a week |
| 1.725 | Very Active | Hard exercise or sports 6-7 days a week4 |
| 1.9 | Extremely Active | Hard daily exercise or sports and physical job |
Equations have been developed to estimate BMR and RMR when testing is not practical. We use the Harris-Benedict equation for BMR, and the Mifflin equation for RMR.
The Harris-Benedict equation has been the standard for decades and is still the most widely used for estimating BMR. This is why we offer it to our users. However, numerous studies have shown it to be inaccurate for a number of reasons:
According to today's test standards the Harris-Benedict equation does not estimate BMR, but rather RMR. This is because the test subjects did not spend the night at the test facility.
The test subjects used to develop the Harris-Benedict equation did not include an adequate representation of obese people, nor of younger and older people. These omissions continue to become more significant as populations become older and heavier.
While all equations for predicting energy expenditure only make estimates, the Harris-Benedict equation typically overestimates by 5% or more.
Since the Harris-Benedict equation was first published in 1919, a number of studies have attempted to improve it. Of these, none has been shown to produce more accurate results than the Mifflin equation we use for calculating RMR.
For further details please refer to Validation of several established equations for resting metabolic rate in obese and nonobese people, Journal of the American Dietetic Association, September 2003, David C. Frankenfield, et al.
The Harris-Benedict equation for BMR:
For men: (13.75 x w) + (5 x h) - (6.76 x a) + 66
For women: (9.56 x w) + (1.85 x h) - (4.68 x a) + 655
The Mufflin equation for RMR:
For men: (10 x w) + (6.25 x h) - (5 x a) + 5
For women: (10 x w) + (6.25 x h) - (5 x a) - 161
Where:
w = weight in kg
h = height in cm
a = age
Ok, so based on all this fun new information we also need to consider what are goals are.
if we want to lose weight (fat) we now have to adjust numbers accordingly. 1 pound of fat is about 3500 calories, so if we want to lose weight at a healthy rate we would reduce our calorie intake by about 500 calories a day and no more then 800, and sometimes a good starting point is 300 depending on your situation and current health state.
if you want to gain muscle you would do the opposite and increase your intake from 300-800 calories.
don't forget that when makeing your meals that you are using food as your FUEL, so your biggest meals should be pre / post workout if possible as well.
overwhelmed yet? :)
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