By Megrette Fletcher M.Ed., RD, CDE
What exactly is a processed carb? If you have ever asked that question, then keep reading because I would like to talk about processed carbohydrates to try to clear up some of the confusion about this term.
To begin, a processed food is any food that has been changed from its natural state. The act of processing can both enhance digestion and improve the taste. In varying degrees, it can reduce the amount of nutrients a food contains. In recent years, processed foods have come under attack. You might have heard about diets that encourage consumers to engage in “raw” or “clean” eating. These plans focus on how much a food is processed or the amount of additives a product contains.
The Process of Processing
To understand what a processed food is, let’s look at making orange juice. The first step is picking the orange. This is the raw ingredient. In this state, the orange, freshly picked, has the most amount of nutrients. Then the orange is squeezed. One orange typically makes 2 ounces of juice. For juice, the fiber-rich pulp and membranes are discarded. This is the first place where we see the nutritional value decrease. The fiber-rich orange is now a 2-ounce glass of fiber-less juice. If you would like to drink more than 2 ounces of juice, you would have to squeeze another orange. In this example, the number of calories in juice is twice as much as an orange, because you need two oranges to make a single glass of juice. This is an example of how processing can add calories to a food. When orange juice is made commercially, the juice might go through a process of heating – which is pasteurization to eliminate unwanted bacteria – or freezing to preserve or concentrate it by removing the water for more efficient shipping. Many manufacturers strive to create a very consistent product, so they may add carbohydrates to a juice by blending in other fruit or juice or adding sugar. This step changes the amount of carbohydrates in juice and, depending on the other juice added, may decrease the overall amount of vitamins.
Amount of Processing
Processing is not bad. However, consider the amount of processed food you are eating. Most people will process carbohydrates by cooking them. Looking at how you process a potato can help.
Imagine I just baked a potato, keeping the skin on and just popping it in the oven. This is an example of very little processing. If I boil and peel the same potato, I have removed the fiber-rich skin and, through the boiling process, removed a few vitamins and minerals. If I mash the cooked potatoes and add milk and butter, other macronutrients, namely fat, have been added to the potato. The problem with processing is that other macronutrients, especially fat, are typically added, or other nutrients are removed. Adding other macronutrients to a food is not bad or harmful, but it does change the nutrient density of a food. Nutrient density is a tricky concept to understand and even harder to explain to your child. This is where using an analogy is helpful.
When you purchase any item, you need to understand two concepts: its cost and value. When we look at food, the cost is equal to the calories and the value is the nutrients it contains.
Cost = calories
Value = nutrient
How a food is processed will affect both its cost and the value.
Nutrient density is comparing the cost (amount of calories) to the value (amount of nutrient) a food has. A “smart” choice has a lot of value for the cost. This is same for food. If a food is considered nutrient-dense, it has a lot of nutrients per calories. For example, potatoes have a lot of nutrition per calorie. However, when you process potatoes into potato chips, you change this ratio. If you are wondering, did the frying of the potatoes remove the nutrients? It didn’t, but the frying did add a lot of calories (over 100 per serving), lowering the amount of nutrients that chips have per calorie. Using the money example above, the calorie cost of the potato nearly doubled and went from 80 kcal to 150 kcal per 100g serving. Not only did the cost of the chips go up, but there was also a decrease in the value (because potato chips don’t have the fiber-rich skin!).
Understanding nutrient density is an important concept to share with your children. You can do this very easily by using smartphone apps that calculate this equation. My personal favorite is Fooducate. I like this app for a number of reasons, including that the rating is a simple letter grade, ranging from A (very nutrient-dense) to F (very low nutrient density). It offers alternative food choice and an explanation of why a food received a specific rating. However, the real benefit of this phone app is it’s a teaching tool, not another calorie tracker or food diary. I strongly discourage parents from keeping track of their child’s food and eating unless it is medically necessary.
Please remember to sign up for Mindful Eating for Kids newsletter!