Oats Nutrition Facts

Calories, Carbs, and Health Benefits of Oats

oats nutrition facts and health benefits
Verywell / Alexandra Shytsman

Oats are a whole grain, meaning the grain is intact and the kernel is composed of three distinct parts: the bran, endosperm, and germ. Because they are a whole grain, they have more nutrients, including vitamins, minerals, and fiber, then other processed grains. Oats also have more soluble fiber than most grains, much of which is beta-glucan, thought to be beneficial for cholesterol.

Nutrition Facts

The following nutrition information is provided by the USDA for one cup (234g) of oats cooked in water with no salt added.

  • Calories: 166
  • Fat: 3.6g
  • Sodium: 0mg
  • Carbohydrates: 28.1g
  • Fiber: 4g
  • Sugars: 0.6g
  • Protein: 5.9g

Carbs in Oats

Oats are a good source of complex carbohydrate and are available in a variety of cooking forms. If you are looking to modify your carbohydrate intake, note that one cup of cooked oats or one-half cup raw oats is equivalent to almost two slices of bread. Keep in mind that processed (flavored) oats may provide more sugar and carbohydrate.

Although plain oats provide almost 30 grams of carbohydrates in one cup cooked, they're a healthier choice than other breakfast options that would provide similar amounts, like refined bread or bagels.

The glycemic index of rolled oats is estimated to be about 55. As a reference, foods with a glycemic index of 55 or below are considered to be low glycemic foods.

Fats in Oats

Oats are not a high-fat food, but there is some fat in a single serving. The 3.6 grams of fat come from polyunsaturated fat, monounsaturated fat, and a very small amount of saturated fat.

Protein in Oats

Oats are a good source of protein, providing about six grams per serving

Micronutrients in Oats

Oats are a good source of manganese, a component of antioxidant enzymes, important in facilitating bone development and helping to make and break down glucose. Oats are also a good source of iron, magnesium, zinc, and selenium. 

Health Benefits

Oats are a whole grain, meaning the grain is intact and the kernel is composed of three distinct parts: the bran, endosperm, and germ. Because they are a whole grain, they have more nutrients, including vitamins, minerals, then other processed grains. Nutrition experts suggest that we replace refined grains, like white bread, pasta, bagels or other breakfast pastries with whole grain foods to promote satiety and healthy weight management.

Oats also have more soluble fiber than most grains. Soluble fiber is the type of fiber that has been shown to help lower cholesterol, which is why your doctor may recommend starting your day with a filling bowl of oatmeal. Soluble fiber also provides beta-glucan, thought to be beneficial for cholesterol.

While the fiber and protein content is oats is impressive, the fat content isn't high. While a one cup serving is usually the go-to, remember that you can reduce your portion and pair it with fruit, flaxseed, chia seeds, or other healthy options to boost the nutrition in your diet.

Common Questions

How does the calorie and carbohydrate content of oats change from dry to wet?

Cooking oats is usually done with a 1:2 ratio, meaning that for every one part dry you need two parts wet ingredient. Therefore, when cooking, the dry measurement will yield double the serving cooked. For instance, a half cup of dry oatmeal yields one cup cooked.

If you are looking at the label and it reads one-half cup of uncooked oatmeal is 166 calories, 28 grams carbohydrate, 4 grams fiber, and 5.9 grams protein, then it will contain the same amount of calories in one cup cooked. If you eat only one-half cup cooked, you can reduce the calories and other nutrient values by half. 

Are oats gluten free?

Oats are naturally gluten-free, however, many oats get introduced to gluten-containing grains, like wheat, rye, barley, and spelt during farming, transportation, and storage. They become contaminated with gluten and therefore are no longer considered gluten-free. If you are looking for 100 percent gluten-free oats, they must be labeled, gluten-free, so don't assume any oat is gluten-free. 

What's the difference between steel-cut oats and other varieties?

The difference occurs during processing. The more processed an oat is the less cooking time it requires. Typically, an increase in processing will increase the food's glycemic index (how quickly it will raise blood sugar). By definition the different varieties of oats are as follows:

  • Groats: the whole kernel with only the husk removed. 
  • Steel cut oats: (otherwise known as Irish oats) are groat oats that are toasted and cut into tiny chunks with a steel blade. They have a chewier texture when cooked.
  • Rolled oats: typically marketed as old-fashioned oats, these are what we usually use as oatmeal; the groat oats are softened by steaming and then pressed through metal rollers to flatten. This cooks the oats partially.
  • Quick cooking oats: rolled oats that are pressed even thinner than regular rolled oats to speed up cook time and allow more water to penetrate.
  • Instant oatmeal: most typically packaged with added flavors and sugar, this type of oatmeal is made of rolled oats that are pre-cooked and dried. This is not the best choice of oatmeal.

Nutritionally, both steel cut oats and rolled oats are similar. Both are whole-grain oats with all three parts of the grain—the bran, germ, and endosperm—intact. The only differences are their textures and cooking times, which may have differing effects on blood sugars.

Recipes and Preparation Tips

Purchase plain oats without added sugars or flavorings. Opt to flavor your oatmeal on your own with fresh or frozen fruit and spices like nutmeg, cinnamon, and vanilla powder.

Store oats in a tightly closed container in a cool, dry place. Use them by their best buy date.

Oats can be prepared raw, as in overnight oats, or cooked as hot porridge. Oats can also be used in replacing breadcrumbs or as a binder in recipes like meatloaf. Use oats to add fiber and texture to bread and cookies, or make your own low-sugar granola to eat as a snack or as an addition to low-fat yogurt or cottage cheese for a protein and fiber packed meal.

You can also use any of these healthy recipes to explore creative ways to use oats.

Allergies and Interactions

Some people can have allergic reactions to oats. According to the American Academy of Allergy, Asthma, and Immunology, oat allergy symptoms may include itching to the mouth and throat and increased heart rate, although your symptoms may be different. If you are allergic to oats, you may have to avoid not only food products but also beauty and skincare products that contain oatmeal.

Additionally, since there is often cross-contamination between grains during processing of food products, you may need to avoid oats if you have a known allergy to another grain. Seek care from a qualified healthcare provider to get personalized advice about an oatmeal allergy.

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Article Sources

Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial policy to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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