What Are Refined Carbs, Exactly?

One clear example of a refined grain as a single food item is white rice—brown rice that’s had the bran and germ removed. Most of the refined grains we consume, though, are in the form of flours milled from refined grains. One example of this is wheat flour, which is ground from wheat that has had the bran and germ removed. (This is the same thing as good ol’ white flour, or all-purpose flour, which is just wheat flour that has been bleached.) This flour is used as a main ingredient in a number of baked goods and packaged foods like bread, muffins, crackers, pretzels, and cookies. 

How refining a grain alters its nutritional value

When you consume a whole grain or whole grain flour, you’re getting all of the fiber, protein, vitamins, minerals, and nutritious fats that they have to offer, per the FDA. In refined grains, the bran and germ have been removed—along with all of that inherent nutritional value. That’s the main beef that nutrition experts have with refined grains. “You are missing out on the many nutrients provided by the whole grain,” board-certified health and wellness coach Kim Larson, RDN, tells SELF.

The particular nutrients that are lost during the refining process depend on what whole grain you start with. In general, though, per the FDA, much of the grain’s fiber and key vitamins and minerals, such as iron and the B vitamins niacin, riboflavin, and thiamin, and sometimes some protein, are removed during processing. Refined flours are then usually enriched, meaning some of those key nutrients lost during processing have been added back in, the FDA explains. But fiber isn’t typically added back in, meaning most refined grains have very little fiber, if any. 

Take a grain that’s common in both whole and refined iterations: wheat. According to the U.S. Department of Agriculture nutrient database, 100 grams of whole wheat flour contain about 71.2 grams of carbs and 10.6 grams of fiber. Refined wheat flour, on the other hand, contains a similar amount of carbs (74.6 grams), but considerably less fiber (3 grams) per 100 grams, according to the USDA. It also contains less protein—only 12 grams per 100 grams versus whole wheat flour’s 15.1 grams.

For an example of how that translates into packaged foods, consider a slice of 100% whole wheat bread versus a slice of white bread (of the same size and from the same manufacturer). The whole wheat slice has 12 carbs, 2 grams of fiber, and 3 grams of protein, while a slice of the white bread has 14 carbs, 0 grams of fiber, and 2 grams of protein. Of course, differences of one or two grams of fiber and protein seem small, and in the grand scheme of your overall food intake, they are. But if you’re consistently choosing refined grains over whole ones, you’ll miss out on some pretty good chances to consume these good-for-you nutrients.

Fiber is probably the most concerning nutrient loss, Larson says, given that most Americans already aren’t getting enough of it, according to the U.S. National Library of Medicine. Fiber has a slew of health benefits—helping to regulate digestion, bowel movements, blood sugar levels, LDL cholesterol, and more. And while it’s possible to get fiber in other foods you eat (like fruits, veggies, and nuts), whole grains are notoriously a great source of fiber that aren’t to be overlooked. 

How to distinguish between whole and refined grains on nutrition labels

When you’re just talking grains by themselves, it’s pretty simple. If you’re buying a whole grain to cook with, for instance—like oats, bulgur, or rice—then the only ingredient on the package should be that whole grain. (Or it should at least be the first ingredient in the case of something like microwave popcorn that also contains oil and salt.) But what if you’re buying something like bread, crackers, or some other packaged food made with grains at the grocery store and you’re hoping to add more whole grains to your plate?