Nutrition Lableing Inconsitency
Food manufacturers are permitted to use fairly liberal averages in their nutrition labeling. Serving sizes of less than 50 calories are rounded to the nearest five calories (a 47 calorie food is rounded to 45 calories). Serving sizes larger than 50 calories are rounded to the nearest ten calories (a 96 calorie food is rounded to 100 calories).
Food labels are also rounded to the nearest whole number. That might not seem like a big deal, but it can add up over the course of an entire day when the total calories per serving listed on the package don’t reflect the calories actually eaten in the form of carbs, protein and fat.
Each carb and protein gram contains 4 calories while each fat gram contains 9 calories. For example, a food with 10 grams of protein, 10 grams and carbs, and 10 grams of fat should have 170 calories, however, with all the averaging taking place, the package may not reflect the actual calories listed in your macros.
The Fittur algorithm analyses the rounding errors and adjusts your macros, particularly your carbs, in order to provide the most accurate measure possible for your macro targets.
Example Calculation of Your Macro Target
The following example calculates the calories, carbs, protein, fat, fiber, additional calories from exercise, and the calorie deficit or calorie overload for a 150 pound person. The calculations for Alcohol, Exercise, BMI, Military Body Fat Percent, Net Carbs, Pregnancy Calories, and Breast Feeding Calories follow this initial calculation example.
Resting Daily Energy Expenditure Calculation (RDEE)
First, convert body weight from pounds to kilograms:
150 lbs / 2.2 = 68
Second, your app determines lean body mass by multiplying body weight by percent body fat:
68 kg. x 20% body fat = 13.6 kg of body fat
Next, subtract body fat weight from total body weight to determine lean body mass:
68 kg – 13.6 kg = 54.4 kg
Now multiply by 21.6 to get the Resting Daily Energy Expenditure (RDEE)
54.4 x 21.6 = 1,175 calories
Finally, calculate the RDEE by adding 370 calories:
1,175 calories + 370 calories = 1,545 calories RDEE
Protein Target Calculation
Establish the protein calories by multiplying body weight by the number of grams of protein per pound of body weight. If the subject is near 10% body fat then that number is 1.1 grams per pound:
150 lbs x 1.1 = 165 grams of protein per day
The following table is for each five percent change in body fat.
15% body fat multiply your weight by 1.0
20% body fat multiply you weight by .95
25% body fat multiply your weight by .90
30% body fat multiply your weight by .85
over 35% body fat multiply your weight by .80
Since each gram of protein has four calories, multiply this number by four:
150g protein x 4 =
600 protein calories per day
Dietary Fat Calculation
After calculating the protein target our 150 pound example with 945 calories remaining:
1,545 calories – 600 protein calories = 945 calories remaning
Assign between 20% and 25% of the remaining calories to the dietary fat target. The higher the body fat level, the closer the calculation assigns dietary fat at 25% of remaining calories. The lower the body fat, the closer the calculation assigns dietary fat at 20% of remaining calories. Over 30% body fat the calculation is set at 25% of remaining calories. Below 15% body fat the calculation is set at 20% of remaining calories. Between 15% and 30% body fat, the dietary fat target assign the percent of remaining calories on a sliding scale.
945 calories x .25 = 236 dietary fat calories
Each fat gram has 9 calories, determine out how many grams of fat to eat by dividing by 9:
236 fat calories / 9 = 26 g of fat to eat
Carb Target Calculation
The remaining 709 calories are assigned as carb calories. Each each carb gram has 4 calories, calculate how many grams of carbs to eat by dividing by 4:
709 carb calories / 4 = 177 g carbs
Fiber Target Calculation
The fiber target can be adjusted in the app to fit any diet reccomendation. The default calculation is 20 grams of fiber per 1,000 calories
Alcohol Calculation (*beginning January 2021)
The consumption of alcohol reduces the remaining daily calories in your calorie countdown by seven calories per one gram of alcohol consumed.
1 gram alcohol = 7 calories
Your carb, protein and fat targets will be reduced proportionally to make up for the difference in energy consumed from alcohol. For example, if you consume 10 grams of alcohol equal to 70 calories, then one third (23 calories) will be counted down (removed) from each of your carb, protein and fat targets like this:
23 carb calories = 6 gram reduction of your carb target
23 protein calories = 6 gram reduction of your protein target
23 fat calories = 3 gram reduction of your fat target (*fat contains about twice as many calories per gram as carbs or fat)
*Note: At the end of the day when you’re approaching zero grams left of any macro target is the moment when you are most likely to notice that your macro targets are suddenly reduced after consuming alcohol. Remember that alcohol calories will be reflected in a sudden proportionally equal reduction in all your targets except for Fiber.
Exercise Calorie Calculation
To calculate the additional calories from exercise, multiply the amount of time the subject exercises by the MET value (metabolic equivalent of task).
You can look up the MET value for your exercise or activity on this table.
If you selected weight lifting as your exercise, then, multiply the time you lift weights in minutes by the MET value to get the number of calories you burn:
90 minutes x 6.0 = 540
Add the exercise calories to the total calories after the protein target is calculated. Exercise calories increase the carb and fat target, but the protein target doesn’t change with exercise.
Summary of Target Calculation With Exercise Added
The new targets for a 150 pound person with exercise added look like this:
Calories = 1,545 + 540 = 2,085
Carbs = 177g + 101g = 278g
Protein = 150g
Fat = 26 g + 15g = 41g
Calorie Deficit Calculation
The ideal calorie deficit is 20 to 30% fewer calories than you burn each day. Use the calorie dial to select the calorie deficit or overload, then either add or subtract the percent of calories adde or removed from the daily calorie intake. Here’s what the final targets look like for a 150 pound person in a 25% calorie deficit (calorie dial set at 75%):
Calories = 1,563
Carbs = 208 g
Protein = 150 g
Fat = 31 g
Military Body Fat Calculation
For males: % body fat = 86.010 x log10(abdomen – neck) – 70.041 x log10(height) + 36.76
For Females: % body fat = 163.205 x log10(waist + hip – neck) – 97.684 x log10(height) – 78.387
703 x weight (lbs) / [height (in)]2
weight (kg) / [height (m)]2
First Trimester: No additional calories added to diet
Second Trimester: 340 calories added if percent body fat is below 20%. For each additional percent body fat, 28.33 calories are added to the diet through 32% body fat. Above 32% body fat, no additional calories are added to the diet.
Third Trimester: 452 calories added if percent body fat is below 20%. For each additional percent body fat, 37.66 calories are added to the diet through 32% body fat. Above 32% body fat, no additional calories are added to the diet.
*The macro nutrients are calculated using the same formulas as indicted above.
Breast Feeding Calculation
During breast feeding, 500 additional calories are added to the diet if body fat percent is at 15% or lower. For each one percent increase in body fat from 16% to 40%, 20 fewer calories are added to the diet. Above 40% body fat 200 calories are added to the diet.
*The macro nutrients are calculated using the same formulas as indicted above.
Calories From Carbs & Fiber
Fiber is a type of carb that doesn’t digest and dump caloric energy in the form of glucose into the blood stream like non-fibrous carbs which dump their entire load of 4 calories of energy per gram into the blood stream. The fibrous carbs that don’t digest are called insoluble fiber. You get zero calories of energy from them. However, the soluble fibrous carbs, simply called soluble fiber, dump about half of their calories (about 2 calories per gram) into the blood stream.
When you scan or search for foods, fittur analyzes the total calories, protein and fat, then, based on the insoluble and soluble carbs in the fiber, assigns the total net carbs of “energy” you get from any food. Here’s the calculation for how many calories you get from carbs and fiber combined:
Total Calories From Carbs = Calories From Carbs (4 calories per gram) + Calories From Soluble Fiber (2 calories per gram)
Net Carb Calculation
Another way of describing the calories you get from carbs and fiber (see above) is by expressing calories in terms of the total carbs or “net carbs” that you digest. The net carbs calculation takes into account the amount of energy that comes from combing the carbs and soluble fiber you eat into a measure called net carbs. One carb gram provides 4 calories of energy per gram while one soluble fiber gram provides half that, 2 calories per gram. Here’s an important ratio to remember when calculating net carbs:
1 carb gram = 2 soluble fiber grams
*Note: the amount of soluble and non-soluble fiber varies from food to food. If the package reads 8 grams of fiber, one gram may be soluble and the rest insoluble for a total of only two additional calories. However, another food with the same number of 8 fiber grams may have 6 soluble fiber grams for a total of 12 calories.
Fittur calculates the soluble and insoluble fibers grams based on the calorie total and then calculates your net carb target. Here’s the calculation for determining net carbs:
Net Carbs = carb grams (4 calories per gram) + 1/2 soluble fiber grams (2 calories per gram)
Supporting Research & Explanatory Details
Fittur calculates daily nutrition targets (calories, carbs, protein, fat, and fiber) based on the Resting Daily Energy Expenditure (RDEE) and the Total Daily Energy Expenditure (TDEE) of each individual using body weight, body fat, activity/exercise level, and self-selected calorie deficit or calorie overload. The following research and explanations support the calculations used to generate the RDEE and TDEE as well as how those calories are divided between carbs, protein, and dietary fat.
Predictive Equations For Estimating Resting Energy Expenditure
Comparison of Estimates of Resting Energy Expenditure
New Approaches to Body Composition Evaluation
The Role Of Macronutrient Content in the Diet For Weight Management
Effect of Macronutrient Composition On Short Term Food Intake and Weight Loss
Effects of Macronutrient Composition on Body Composition and Fat Distribution During Weight Maintenance and Weight Loss
Body Fat Mass and Macronutrient Intake in Relation to Circulating Soluble Leptin receptor, Free Leptin Index, Adiponectin, and Resistin Concentrations In Healthy Adults
Body Macronutrient Composition Is Predicted by Lipid and Not Protein Content of the Diet
Physical Activity Energy Expenditure in Successful Weight Loss Maintainers
The Effect of Exercise on Non-Exercise Physical Activity and Sedentary Behavior in Adults
A New Predictive Equation For Resting Energy Expenditure In Healthy Individuals
A Predictive Equation To Calculate Resting Metabolic Rate In Athletes
Comparison of Methods to Assess Energy Expenditure and Physical Activity in People With Spinal Cord Injuries
How Many Calories Do You Need?
Energy Expenditure Formulas: Basal Metabolic Rate and More, Wikipedia