Key takeaways:
Refined grains start as whole grains. But they go through processing that removes most of their fiber and other nutrients.
Eating high amounts of refined grains is linked to an increased risk of heart disease, Type 2 diabetes, and weight gain.
You don’t need to avoid refined grains entirely, but you should try to make at least half of your grains, whole grains.
You may have heard that you should limit refined grains in your diet. But what are refined grains, and which foods contain them?
White bread, pasta, and white rice are common examples of refined grains found in many Western diets. It’s OK to eat refined grains in moderation, but a diet high in refined grains can have a negative impact on your health. Let’s take a closer look at what refined grains are, how they impact your body, and how to identify them.
What are refined grains?
Refined grains are whole grains that go through processing, or “refining.” Since refined grains start as whole grains, it helps to first understand what a whole grain is.
A whole grain contains all of the naturally-occurring parts of the grain seed, including the:
Bran: The outer layer, which contains fiber and antioxidants
Germ: The small inner core, which contains B vitamins, minerals, protein, and healthy fats
Endosperm: The starchy interior, which is mostly carbohydrates, with a small amount of vitamins and minerals
Food manufacturers sometimes mill, or refine, whole grains to extend their shelf life and create a finer texture. This process removes the bran and germ. But it also ends up removing most of the grain’s fiber, vitamins, minerals, and antioxidants.
The result is a refined grain that’s primarily starch. It’s much lower in fiber and is less nutritious overall than the original whole grain. These refined grains can then be processed even further, like turning refined white flour into white bread.
Some refined grains are enriched, which means certain nutrients are added back during manufacturing. But the fiber and antioxidants aren’t replaced. A common example is enriched all-purpose flour. This is white (refined) flour with added iron and B vitamins.
Examples of refined grains
Many types of grains can be refined. The most common refined grains are wheat, rice, and corn. Here are some examples of each.
Wheat
Whole wheat is refined into flour that’s used to make:
Bread, bagels, and flour tortillas
Crackers
Pretzels
Pasta and couscous
Boxed breakfast cereals
Cookies, pastries, muffins, and other baked goods
Rice
You can eat refined rice (white rice), or foods made from refined rice flour, like:
Noodles
Crackers
Bread
Cereal
Corn
Corn is a whole grain that can be refined into cornmeal or corn flour to make:
Corn bread
Tortillas and arepas
Polenta
Breakfast cereals
Grits
Note that certain grains are almost always eaten whole because refining them is uncommon. Examples include oats and the ancient grains millet, bulgur, and quinoa.
Whole grains vs. refined grains
The table below compares some refined grains with their whole-grain counterparts.
Type of grain | Refined grain foods | Whole grain foods |
Wheat | Refined wheat flour Couscous Cream of wheat | Whole wheat flour Wheat berries Farro Freekeh Bulgur |
Rice | White rice flour White rice | Brown rice flour Brown rice Black rice Red rice |
Corn | Refined corn flour Refined cornmeal Grits | Whole grain corn flour Whole grain cornmeal Popcorn |
Barley | Pearled barley | Whole barley flour Pot barley Hulled barley |
Rye | Refined rye flour | Whole rye flour Rye berries |
Oats | No refined version | Oat flour Oat groats Steel-cut oats (Irish oats) Rolled oats (old-fashioned oats) Instant oats |
Ancient grains | No refined versions | Quinoa Millet Amaranth Sorghum Teff |
Downsides of refined grains
During the refining process, grains lose many nutrients, especially fiber. Without fiber, many of the grain’s benefits are lost. Eating high amounts of refined grains can increase:
Risk of Type 2 diabetes: Refined grains cause your blood sugar to rise quickly.
Weight gain: Without fiber, refined grains don’t keep you full for long. So you may eat more calories overall. Blood sugar spikes from eating refined grains can lead to food cravings. Studies suggest that a diet high in refined grains may increase weight, waist circumference, and abdominal fat.
Heart disease risk: Eating a lot of refined grains is linked to heart disease and high blood pressure. A higher body weight and higher blood sugar can also negatively affect heart health.
Inflammation: Refined sugars can increase inflammation, unlike naturally-occurring sugars (like those in fruit and milk). High blood sugar can also lead to increased inflammation in your body.
Cancer risk: A high intake of refined grains is linked to increased risk of colon and stomach cancer.
Benefits of whole grains
Observational studies suggest that eating whole grains may be linked to:
Reduced risk of heart disease and stroke: The American Heart Association (AHA) recommends eating whole grains. That’s because whole grains lower the risk of heart disease and stroke by helping to regulate blood pressure, cholesterol, and triglycerides.
Better blood sugar control: The fiber in whole grains slows sugar absorption in your gut, preventing blood sugar spikes. This can make it easier to manage your blood sugar levels, especially if you have diabetes.
Reduced inflammation: Fiber, antioxidants, and other nutrients in whole grains may work together to reduce inflammation in people with higher weight or diabetes. This can lower your risk of developing many chronic health conditions.
Weight management: Eating whole grains is linked with a lower risk of weight gain. Whole grains may support weight goals by promoting fullness (from both fiber and protein) and increasing the diversity of bacteria in your gut.
Reduced cancer risk: The fiber and antioxidants in whole grains may decrease your risk of developing and dying from certain cancers, including colon, stomach, and pancreatic cancer.
But it’s not clear how much whole grain you need to eat to get these health benefits.
How can you tell if a food has refined grains?
Once you know what to look for on food labels, it’s easy to spot refined grains. Look for words like:
Wheat flour (without the word “whole”)
White flour
All-purpose flour
Enriched wheat flour
Semolina or durum semolina (unless it says “whole”)
Cake, pastry, or bread flour
Rice flour (unless it’s listed as brown rice flour)
Corn flour (unless it’s listed as whole-grain corn flour)
Brands that use whole grains usually boast about it on their packaging (for good reason). Labels may say “Made with whole grains.” You can also look for the Whole Grains Council’s Whole Grain Stamp, on food packages like breakfast cereals.
Frequently asked questions
The healthiest grains to eat are whole grains because they have more fiber, antioxidants, and vitamins than refined grains. But there’s no single “healthiest” grain. Experiment with different whole grains — such as brown rice or oats — to see what you like. You can also try ancient grains, like quinoa, teff, and sorghum. Some of these grains are also high in protein.
You don’t need to avoid refined grains entirely. That would be hard to do since they’re everywhere. A good rule of thumb is to make at least half of the grains you eat whole grains. With little effort, you can usually swap refined grains for whole-grain alternatives. For example, you can choose 100% whole wheat bread or pasta, brown or wild rice, or whole corn tortillas.
No, oatmeal isn’t a refined grain. Whether steel-cut or rolled, oatmeal is made from whole oats that contain all three parts of the grain: the bran, germ, and endosperm. Instant oatmeal is more heavily processed than other types of oats and often contains added sugars or flavors. But even instant oatmeal generally uses whole oats, so it’s still considered a whole grain.
The healthiest grains to eat are whole grains because they have more fiber, antioxidants, and vitamins than refined grains. But there’s no single “healthiest” grain. Experiment with different whole grains — such as brown rice or oats — to see what you like. You can also try ancient grains, like quinoa, teff, and sorghum. Some of these grains are also high in protein.
You don’t need to avoid refined grains entirely. That would be hard to do since they’re everywhere. A good rule of thumb is to make at least half of the grains you eat whole grains. With little effort, you can usually swap refined grains for whole-grain alternatives. For example, you can choose 100% whole wheat bread or pasta, brown or wild rice, or whole corn tortillas.
No, oatmeal isn’t a refined grain. Whether steel-cut or rolled, oatmeal is made from whole oats that contain all three parts of the grain: the bran, germ, and endosperm. Instant oatmeal is more heavily processed than other types of oats and often contains added sugars or flavors. But even instant oatmeal generally uses whole oats, so it’s still considered a whole grain.
The bottom line
All grains start as whole grains, but some are milled to make refined grains. Manufacturers may refine grains to modify the taste, texture, or shelf life. But with their fiber removed, refined grains provide fewer benefits for your heart, blood sugar, or weight. And in high amounts, refined grains can increase your risk for certain health conditions. It’s difficult to fully avoid refined grains, and you don’t need to. Try to replace refined grains with whole grains when you can. Even small changes can make a difference.
Why trust our experts?
References
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