A few days ago we got an email from Bob, who was befuddled by Coke’s
Thirty-nine grams of sugar at 4 calories per gram yields 156 calories, right? So how can there only be 140 calories in a 12 oz can of Coke? Or, am I not seeing something?
We wrote to Coke’s consumer affairs group, and this was their reply:
Thank you for contacting The Coca-Cola Company. We appreciate this opportunity to assist you.
Under the Nutrition Labeling and Education Act (NLEA) passed by Congress in 1990, serving size is based on either a reference amount or a container size.
Products with less than five calories per serving are rounded to zero calories; products with 5-50 calories are rounded to the nearest 5-calorie increment; and products with over 50 calories are rounded to the nearest 10-calorie increment.
A 12-ounce serving of Coca-Cola classic has 39 grams of carbohydrate
(39 grams of carbohydrate) x (3.66 Calories) = (142.74 Calories)
FDA guidelines allow beverage companies to round calories to the nearest 10-Calorie increment, so 142.72 Calories is rounded to 140 Calories
We hope this information is helpful. Should you have additional questions or comments, please feel free to contact us again.
Industry and Consumer Affairs
The Coca-Cola Company
Get it? Carbs are not 4 calories per gram, but rather 3.66. But how can this be? We’ve been taught that fats are 9 calories to the gram, while carbs and protein are 4 to the gram. But the truth, as always, is more complicated. The 4-4-9 paradigm is a simplification that makes it easy to quickly assess and calculate calorie values.
Calories have been measured in the same way for 100 years using the Atwater method – basically burning the food in a special receptacle (calorimeter) and measuring the heat output. Energy is energy. Using this method, hundreds of basic foods were burned and their measurement taken. The values for carbs are on average 4 calories per gram. But for glucose, which is what sugar and high fructose corn syrup in soda break down to, the value is 3.68. And so why wouldn’t Coke choose that as their base for calorie calculation.
But wait, calorie determination is even more complicated. The calorimeter is not not an exact approximation of human metabolism. Each one if us will be impacted slightly differently by foods we eat. Not everything we eat is digested (fiber in fruit) and that can also impact the calories actually absorbed by the body.
In summary, calorie information should be used as an approximation. If you are comparing 2 products, one with 160 calories and the other with 140 calories – opt for the product with the better ingredients.