Are Oats Bad for You? We Investigate



During the cold winter months, a warm bowl of oatmeal starts to feel like a far more desirable breakfast option than smoothies, yogurt, and a lot of other foods we reach for when the weather is more mild. But as with many other grains, there’s some confusion surrounding whether oats are even a healthy option.

To clear the confusion, we spoke with nutritionists Rachel Fine, Nia Rennix, and Julie Cunningham. Keep reading to see what they have to say about oats. 

Are Oats Bad for You?

Not at all, nutritionists say. In fact, oats are loaded with soluble fiber, which slows digestion, keeps you full for a long time, helps you maintain steady energy levels, and has even been shown to lower LDL (or “bad”) cholesterol levels. Oats are also a whole grain, and they’re filled with fiber that promotes healthy digestion. That’s pretty good for a tiny cereal grain, right? 

Beyond fiber, oats are high in protein and loaded with vitamins and minerals like manganese, thiamine (vitamin B1), magnesium, and zinc. And the benefits don’t stop there—oats are also associated with a reduced risk of heart disease and type 2 diabetes.

Do Oats Contribute to Weight Gain?

You may have heard that oats contribute to weight gain, but oats can absolutely be part of a healthy diet without contributing to weight gain, nutritionists say. “Any food, if eaten in excess, can contribute to weight gain, but oats are not a food that is likely to be a big culprit when it comes to putting on weight,” says registered dietitian Julie Cunningham. That healthy fiber we mentioned before plays an important role here. “Because oats have a lot of fiber, a person is likely to feel full before he or she can take in lots of calories from oats,” Cunningham adds. Plus, oats tend to digest slowly, keeping you full for longer than many other foods. For this reason, oats are often recommended as a great food choice for weight loss and control.  

Oats may have mood-boosting benefits, too. “Oats initiate serotonin production in your brain to give you a calm feeling,” says clinical nutritionist Nia Rennix. “Because of this, they can support in aiding depression and mood improvement.”

Like most other foods, you’ll want to be mindful of how much you’re eating. A healthy portion of oats varies depending on the type of oats you choose, but a typical serving size is usually around a ½ cup of dry oats, which leaves you with around one cup of cooked oats. A cup of cooked oats contains around 150 calories, five grams of protein, three grams of fat, 27 grams of carbohydrates, four grams of fiber, and one gram of sugar. Remember that these nutrition stats don’t account for toppings or mix-ins though. 

Many of the tastiest oatmeal toppings are loaded with sugar, so it’s important to watch what you add. It’s really easy to get carried away and add too much sugar to your oats. Fruit is a healthy, low-calorie way to sweeten up your oats, but if you use sugar, honey, maple syrup, and other sweeteners, moderation is key.One serving of maple syrup can have more than 50 grams of sugar, and just one tablespoon of honey has around 16 grams of sugar. 

The Dietary Guidelines For Americans recommends limiting calories from added sugars to 10 percent or less of your daily intake. So for a 2000 calorie diet, that’s 200 calories or 12 teaspoons of added sugars.


Should I Stay Away From Instant Oats?

Instant oats are a bit lower in fiber, so they may not promote the same health benefits as oats that are higher in fiber, explains registered dietitian Rachel Fine. Sugar is another potential problem area with instant oats. If you’re buying flavored, individual-size servings, it’s important to keep an eye on the nutrition label to make sure the sugar content isn’t too high. “The sugar content of instant oatmeal varies widely with the type that you purchase,” Cunningham says. “Overall, it's still a pretty good choice provided that you choose a lower sugar option.”

Are Steel-Cut Oats Healthier Than Other Types? 

Steel-cut oats are minimally processed and don’t have any added sugars, but they take longer to cook. They also take longer to digest, have a slightly higher fiber content, and may have a lower glycemic index (which means they release energy more slowly and have less of an impact on blood sugar) than rolled or instant oats. 

“If you have extra time, they're a good choice,” Cunningham says. “If you don't, there's nothing wrong with regular rolled or quick-cooking oatmeal.”

What Are Some Healthy Ways to Prepare Oats?

Fine suggests making an oatmeal parfait using pre-cooked steel-cut or rolled oats, and it sounds pretty delicious: “Scoop ⅔-cup of cooked grain and layer with Greek yogurt and raspberries. Top the parfait with 2 tablespoons of chopped nuts and a drizzle of honey.”

You can also make overnight oats, which are one of the simplest breakfast choices because, as the name implies, you prep them the night before. Of course, your standard bowl of oatmeal is always a good choice as well, especially if you use healthy toppings and mix-ins like fruit, nuts, and seeds. “I love eating cooked oats topped with walnuts, pecan milk, and a sprinkle of sugar substitute,” Rennix says. 

The Final Takeaway

Oats—steel-cut, rolled, or instant—are a great choice when you’re looking for something healthy to eat for breakfast, or really at any time of day. But the key is to be sure not to overdo it on sugary toppings. And if you’re reaching for a packaged variety, make sure it isn’t loaded with added sugar—the calories add up and no one likes a sugar crash. Finally, remember to always reach out to your physician if you have any questions or concerns about your health, as it relates to eating oats or otherwise. 

Article Sources
Byrdie takes every opportunity to use high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial guidelines to learn more about how we keep our content accurate, reliable and trustworthy.
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