Are Carbs Bad for You? Here's What Dietitians Have to Say

Despite a growing belief that carbs are bad for you, they actually provide loads of health benefits.

an illustration of various types of carbs with question marks surrounding them
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There's a common misconception that carbohydrates are bad for you. You may even worry that eating them causes health issues, but carbs are an essential part of a healthy eating pattern. They need not be feared; in fact, they should be celebrated for the energy they give us. Learn more about carbs' benefits and potential downsides and how to incorporate them into a healthy diet.

What Are Carbs?

Carbohydrates are one of three macronutrients (the other two being protein and fat). They’re made up of sugar molecules that break down into glucose during digestion. Common carbohydrate-rich foods are bread, rice, pasta, cereal, tortillas, fruits and starchy vegetables like potatoes.

Types of Carbs

Carbohydrates are not all the same. There are a few different types of carbohydrates, per MedlinePlus:

  • Sugars: These are also known as simple carbohydrates. They’re found in table sugar and foods with added sugars, like cookies, cakes and sweetened yogurt. They’re also found in fruits, some veggies and dairy products.
  • Starches: These are also known as complex carbohydrates because they’re longer chains of sugars. Your body breaks starches down into sugars for absorption, which takes longer than digesting sugars. They’re found in foods like pasta, rice, bread, cereal, corn and potatoes.
  • Fiber: This type of carbohydrate can’t be digested by the body. “Fiber is such an important nutrient that helps aid in bodily functions like blood sugar control, heart health, digestion and satiety,” says Haley Bishoff, RD, LD, a plant-based dietitian and owner of Rutsu Nutrition in Las Vegas. You can find fiber in fruits, veggies, legumes and whole grains.

Benefits of Carbs

Carbs Give You Energy

The main benefit of carbs is their energy-boosting power. Bishoff says that carbs are our bodies’ primary source of energy and fuel. “Carbohydrates provide our cells with glucose, which is converted to energy used to support important bodily functions and metabolism,” adds Wan Na Chun, M.P.H., RD, CPT, of One Pot Wellness in Indianapolis.

Carbs Fuel Your Brain

You may notice that your concentration and focus suffer if you’re cutting back on carbs. That’s because carbs don’t just give your body energy; they also power your brain. In fact, about 20% to 25% of your body's resting glucose consumption goes to fuel your brain, per a 2018 review in the Journal of Pediatric Gastroenterology and Nutrition.

Complex carbs like whole grains or high-fiber foods are particularly beneficial carbohydrates for your brain. These kinds of carbs promote stable blood sugars, which can support more sustained concentration and focus.

On the other hand, mostly relying on refined carbohydrates like a candy bar may lead to rapid spikes in your blood sugar and then rapid crashes. If these quick shifts happen a lot, it could cause brain fog. 

Carbs Support Muscle Recovery

Since carbohydrates are your body’s primary energy source, eating enough carbs is especially important if you’re an athlete or an active individual. During bouts of physical activity, your body turns to the storage form of glucose—glycogen—that you get from eating enough carbs. In fact, a 2023 review in Current Opinion in Clinical Nutrition & Metabolic Care concluded that restricting carbs hinders muscle growth and anaerobic performance. Another study published in 2018 in Nutrients found that consuming carbs after a workout is key for restoring muscle glycogen and increasing athletes’ exercise capacity.

Carbs May Boost Your Mood

Researchers suspect that carbs promote the production of serotonin, a feel-good brain chemical. In a 2023 meta-analysis in the Journal of Affective Disorders, researchers found that a low-carb diet may increase anxiety. Older studies, like a 2009 one from the Archives of Internal Medicine, have linked low-carb diets with increased feelings of depression, anxiety and anger, compared to low-fat, high-carb diets.

Carbs Promote Heart Health

Eating certain types of carbs may reduce your cholesterol, which helps prevent heart disease and stroke. Specifically, research suggests that increasing your intake of soluble fiber (a type of fiber found in carb-rich foods like oats, barley and beans) by 5 to 10 grams daily could result in a 5% drop in "bad" LDL cholesterol, per the Department of Health and Human Services. Similarly, people who eat more whole grains (think whole-wheat bread, oatmeal, quinoa) also tend to have lower LDL cholesterol and higher "good" HDL cholesterol.

Carbs Support Healthy Digestion

Many carbohydrates contain fiber, a key nutrient for digestion. Whole grains like oatmeal, quinoa, whole-wheat bread and corn, veggies, fruits and legumes are good sources of carbs and fiber. Soluble fiber can help slow digestion if you struggle with diarrhea. In contrast, insoluble fiber (found in wheat bran, veggies and whole grains) can help treat constipation by speeding up gastric motility and adding bulk to the stool, per MedlinePlus.

Downside of Carbs

If you have prediabetes or diabetes, you may need to be more mindful about your carb intake. Chun explains, “Individuals with diabetes have a decreased ability to process or use insulin, which is the main hormone that regulates blood sugar levels.” This doesn’t mean that you need to eliminate carbs, but it’s important to eat more fiber and pair carbs with protein and fat to prevent blood sugar spikes. 

Similarly, Chun says, “[People] with polycystic ovary syndrome (PCOS) often experience insulin resistance and should also be mindful of their carbohydrate consumption to minimize the potential health risks.” Bishoff agrees and says, “There are plenty of healthy carbohydrate foods that can still be eaten despite these diagnoses.” She suggests whole grains and other complex carbs like fruit, sweet potatoes, chickpea pasta, quinoa and oats.

How to Incorporate Carbs into a Healthy Diet

“Keep in mind, a doughnut is a high-carb food, but so is an apple. It's all about reducing the highly refined and processed carbs, especially those with added sugar,” says Bishoff. According to the Centers for Disease Control and Prevention, the Dietary Guidelines for Americans recommend limiting added sugars to no more than 10% of your caloric intake.

Adding more nutrient-dense foods like whole fruits and veggies, legumes and unsweetened dairy products helps you eat more complex carbs and reduce refined carbs and added sugars. Bishoff suggests swapping white bread for whole-grain bread and purchasing plain oats instead of pre-sweetened varieties packed with added sugars. For inspiration, try this Cinnamon Roll Overnight Oats recipe that contains only 4 grams of added sugar or this Chickpea Salad Sandwich recipe with 12 grams of fiber.

Frequently Asked Questions

What are the worst carbs to eat?

Different carbs will be best at different times. That being said, consuming too many added sugars is associated with poor health outcomes. These are found in foods like cake, cookies, candy, sweetened beverages and sweetened yogurt.

What carbs are the healthiest?

Whole grains, fruits, starchy vegetables, legumes and dairy products are high-carb foods that can promote heart, digestive, metabolic and bone health.

Are carbs worse for you than sugar?

Sugar is one type of carbohydrate. Sugars found naturally in foods like fruit do not harm your health in the way that added sugars can.

Is it better to stop eating sugar or carbs?

Most people would not benefit from eliminating sugar or carbs. Sugar is one type of carb, and it’s found naturally in nutrient-rich foods like fruit and vegetables. Eating all kinds of carbs is important for energy levels, brain function, muscle recovery, digestion, heart health and more. 

The Bottom Line

Carbohydrates get a bad rap, but they provide loads of benefits to our health. If you have diabetes or PCOS, you may need to be more mindful of your carb intake, but it doesn’t mean you need to eliminate this important macronutrient entirely. Adding more whole grains and fiber is a great way to support satiety, digestion, heart health and energy levels.

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