Carbohydrates: Main Function, Best, and Worst Types (2024)

A carbohydrate, or “carb,” is a macronutrient that provides energy. Macronutrients are special nutrients your body requires in large amounts to function. The other two main macronutrients are fats and proteins.

Carbohydrates are found in both healthy and unhealthy foods. Natural foods, minimally processed foods, and heavily processed products can all contain them. There are different types of carbs, and some are more beneficial to your health than others.

Your body breaks carbohydrates down into glucose (a form of sugar), the main energy source your cells, tissues, and organs need. Glucose can be used right away or stored up for later.

Carbohydrates and Their Function Explained

Carbohydrates function as an energy source, help maintain blood sugar levels, and affect how cholesterol and triglycerides are metabolized in your body.

When you consume carbs, your digestive system breaks them down into sugars. As blood sugar levels increase, your pancreas releases insulin (a hormone). Insulin transfers sugar into your cells, where it is used as energy. If you have extra sugar, your body stores it in your liver or muscles for later use.

Comparing Types

The three main types of carbohydrates are:

• Sugars: Also called “simple carbohydrates,” these include the types of sugar that are naturally found in vegetables, fruits, and milk. They also include added sugars, which are processed sugars added to foods.
• Starches: Starches are called complex carbohydrates because your body needs to break down starches into sugars before using them for energy. Some examples of starches are pasta, bread, cereal, potatoes, and corn.
• Fiber: Fiber is a type of complex carbohydrate. Fiber is found in foods like fruits, vegetables, beans, nuts, and whole grains. Your body can’t break down most types of fiber, so foods with fiber can help you feel full for longer.

The type of carbs you consume matters when it comes to your health. Generally, the amount of carbohydrates in your diet is less important than the type. Studies suggest eating more complex carbohydrates that contain fiber, such as whole grains, non-starchy veggies, and fruits, is more beneficial for overall health, weight management, and wellness.

Reasons They Are Beneficial

Carbohydrates are an important part of a healthy diet. They provide fuel for your heart, brain, kidneys, and nervous system. Carbs can also give you a boost in energy if blood sugar levels drop.

Healthier carb-containing foods, such as veggies, fruits, whole grains, and beans can provide the following nutrients:

• Fiber: Dietary fiber is a carbohydrate that isn't easy to digest. Fiber has been shown to improve heart health and aid in digestion.
• Vitamins and minerals: Carb-containing foods may contain B vitamins, vitamin C, calcium, iron, potassium, magnesium, selenium, and more.
• Antioxidants. Some carb-containing foods contain antioxidants, which help fight free radicals (reactive molecules that can damage cells) in the body.

Additionally, carbohydrates may help replace energy used up during exercise. Your body needs carbohydrates and protein to recover after physical activity. Some research suggests carbohydrates may also help improve mood by boosting serotonin levels in the brain. Serotonin is a chemical messenger between nerve cells (neurotransmitter) that stabilizes mood.

When Are Carbohydrates “Bad”?

So-called “bad” carbohydrates are added sugars. They’re found in foods such as desserts, candy, soda, breakfast cereals, and other processed products. These carbs contain calories but no vitamins, minerals, fiber, or other healthy nutrients.

Eating a lot of added sugars can lead to weight gain and contribute to other health problems, such as diabetes and heart disease. The American Heart Association recommends limiting foods with added sugars as they only provide empty calories.

Ranking Carbohydrate Foods

The best carbohydrates to consume are unprocessed, complex carbs, such as:

• Dairy products: Milk and yogurt are good options.
• Fruits and vegetables: Eat a wide variety of these. Any type will do.
• Legumes: These include beans and lentils.
• Starchy vegetables: These include green peas, butternut squash, and potatoes.
• Whole grains: These include brown rice, quinoa, whole-grain pasta, whole-grain breads, and bulgur wheat.

Processed carbohydrates to avoid or limit include:

• Added sugars, such as those in candy, baked goods, sugary cereals, syrups, fruit snacks, soda, or other sugary drinks
• French fries
• Potato chips and crackers
• White flour and products made with it, such as white bread
• White rice

How to Count Carbohydrates

Carbohydrates are measured in grams. The U.S. Department of Agriculture (USDA) recommends that adults get 45% to 65% of their daily calories from carbohydrates. That’s about 225 to 325 grams daily if you consume a 2,000-calorie-a-day diet.

You can check your food labels to determine how many carbohydrates an item contains. The USDA also offers a comprehensive food composition database that allows you to look up different foods and find how many carbohydrates they contain.

Who Should Monitor Carbohydrate Intake?

Some people may need to monitor their carb intake. For example, people with type 1 or type 2 diabetes may have to limit or count their carbs. With these conditions, your body doesn’t produce enough insulin or doesn’t use insulin properly, which leads to high blood sugar levels. A dietitian can help you determine how many carbs to consume in a day if you have diabetes.

Summary

While carbohydrates sometimes get a bad rap, your body needs them for energy. The key is to consume the right carbs. Generally, you should steer clear of foods with added sugars. Instead, choose whole, unprocessed items, like vegetables, fruits, and grains. When part of a well-rounded diet, these types of carbohydrates can provide many health benefits.