how to calculate percentage of carbs from total calories?
["Nutrient percentages are the percentage of the day's calories coming from each macronutrient. ... ", 'Carbohydrate calories = Carbs (g) * 4.0.', 'Protein calories = Protein (g) * 4.0.', 'Fat calories = Fat (g) * 9.0.', 'In the example above, the fat calories per gram are higher than protein and carbohydrates.']