Diet Calculations In NYC Nutrition Analysis
NYC calculates four different diet metrics, which are displayed at the bottom of the nutrition display when:
1) nutrition items are selected in the nutrition database (Nutrition... Database...) or
2) nutrition analyses are performed (Nutrition... Analysis) on recipes and meal plans.
In the nutrition analysis, you can get the diet results for the entire recipe or by serving (yield unit).
Calculation of the four individual diet metrics is briefly described below.
Food Blocks of Carbohydrates:Protein:Fat
Some diets use food blocks wherein 1 carbohydrate block + 1 protein block + 1 fat block = 1 total food block. Food blocks in NYC are calculated as:
# carbohydrate blocks = (g carbohydrates - g fiber)/9
# protein blocks = (g protein)/7
# fat blocks = (g fat)/3
%Calories as Carbohydrate:Protein:Fat
Some diets target a specific proportion of calories from carbohydrates, proteins, and fats (e.g., 40:30:30). To make this calculation, NYC assumes that 1 g carbohydrates or protein contains 4 calories and 1 g fat contains 9 calories.
Effective Carbohydrate Count (ECC)
Some diets rely on "net carbs" or effective carbohydrate count, computed as
ECC = g carbohydrates - g fiber .
WW points are calculated as an explicit function of the calories, fats, and fiber present in food that you eat. Specifically, the formulation NYC uses is:
WW = calories/50 + g fat/12 – g fiber/5
where the fiber benefit is limited to a maximum of 3g fiber per oz of food.