What Are Complex Carbohydrates? — And 28 to Add to Your Diet

Carbohydrates (or carbs, for short) are a type of macronutrient — a nutrient your body needs in large amounts. Many foods contain carbs, including fruits, grains, beans, and vegetables. Your body uses carbs for energy, digestive health, and blood sugar control.

You’ve probably heard that certain types of carbs are healthier than others and that complex carbs should be prioritized over refined or simple carbs. 

But what exactly are complex carbohydrates and what sets them apart from other types of carbs?

Here’s everything you need to know about complex carbs including what they are, how they differ from simple carbs, and how to include more of them in your diet. 

What's the Difference Between Simple and Complex Carbohydrates? 

All carbs are made up of sugars such as glucose, fructose, and galactose. Carbohydrates are divided into categories according to the number of sugar units they contain.  

There are two main types of carbohydrates: simple and complex. 

Simple carbs are made up of just one or two sugars while complex carbs are made up of multiple sugar units. 

Simple Carbs 

Monosaccharides are the simplest and smallest type of sugar made of just one sugar unit. When you consume carbs, your body breaks them down into monosaccharides so they can be absorbed and used for energy.

There are three main monosaccharides:

1. Glucose
2. Fructose
3. Galactose

Disaccharides are made of two monosaccharides units bonded together.

There are three main disaccharides:

1. Sucrose (glucose + fructose)
2. Maltose (glucose + glucose)
3. Lactose (glucose + galactose)

Simple sugars like glucose, fructose, and sucrose are found in a number of foods, including healthy foods like fruits and dairy products. 

However, many less healthy, ultra-processed foods are high in simple sugars like high-fructose corn syrup and table sugar. Some examples of foods and drinks high in simple sugars include candy, soda, sugary cereal, and ice cream. 

Simple sugars are easily digested by the body, which causes a rapid increase in blood sugar and a release of the hormone insulin from the pancreas. Additionally, foods rich in simple carbs like candy, soda, and sugary baked goods are high in calories, but low in important nutrients like fiber, protein, vitamins, and minerals. Because of this, a diet too high in simple carbs can increase your risk of developing health conditions like obesity, type 2 diabetes, and heart disease.

Complex Carbs 

Complex carbs or polysaccharides are made from three or more sugars bonded together, which makes it harder for your body to break them down. Because they take longer to digest, complex carbs cause a more gradual increase in blood sugar compared to simple carbs.

There are three main polysaccharides:

1. Starch
2. Glycogen
3. Fiber 

Starch and fiber are the polysaccharides found in food, while glycogen is only found in our bodies. Glycogen is the storage form of carbohydrate in animals and humans. We use glycogen stored in our muscles and liver for energy. 

Starches and fibers are concentrated in foods like fruits, vegetables, beans, and grains. Unlike starches, fibers aren’t digested by the body. Instead, they help promote digestive health by fueling beneficial gut bacteria and keeping bowel movements comfortable and regular. 

Compared to people who eat a lot of simple carbs, people who follow diets high in complex carbs rich in fiber tend to have lower rates of a number of chronic diseases including heart disease and colon cancer. Plus, fiber helps you feel satisfied, which is why people who eat high-fiber diets tend to carry less body fat than people with low fiber intake.

28 Complex Carbohydrate Foods to Eat 

Replacing simple and refined carbs with complex carbs like vegetables, fruits, and beans is an easy way to improve your health. Fortunately, there’s a variety of complex carbs to choose from. Here’s some examples of nutritious complex carbs to add to your diet. 

Whole Grains

Whole grains are grains that contain all three parts of the grain kernel — the germ or core, the endosperm or middle layer, and the hard outer layer called the bran. These parts house important nutrients like fiber, vitamins, and minerals. 

On the other hand, refined grains have their bran and germ removed, which makes them less nutritious. 

Here are some tasty whole grains to try:

1. Quinoa 
2. Oats
3. Brown rice
4. Millet 
5. Farro
6. Buckwheat
7. Brown rice

Pulses

Pulses, like beans and lentils, are types of complex carbs that are packed with fiber, vitamins, minerals, and plant-based protein.

Diets high in pulses have been shown to be protective against health conditions like certain cancers, type 2 diabetes, and digestive diseases.

Here are some examples of pulses to add to your diet:

1. Lentils
2. Chickpeas
3. Black beans
4. Kidney beans
5. Cannellini beans
6. Peas
7. Pinto beans 

Starchy Vegetables 

All vegetables contain carbs, but some are higher in starch than others. If you’re looking for healthy, carb-rich vegetables, give the following a try: 

1. Sweet potatoes 
2. Potatoes
3. Butternut squash 
4. Beets 
5. Acorn squash 
6. Delicata squash 
7. Parsnips 

Fruits

Fruits are some of the most delicious complex carbs you can eat. Not only are they sweet, but they’re high in fiber, vitamins, minerals, and protective plant compounds. 

A 2022 study reported that in 2019, only 12.3% of U.S. adults met the recommended fruit intake of 1.5 to 2 cup-equivalents per day. Not eating enough fruit could negatively impact your health and increase your risk of a number of health conditions, especially if you’re eating highly processed foods instead of fruit. 

To make sure you’re taking in enough fruit every day, try adding some of the following to your diet:

1. Blueberries 
2. Apples
3. Oranges
4. Bananas
5. Peaches
6. Mangoes  
7. Strawberries  

Simple Carbohydrate Foods to Limit and Avoid 

If you’re following a diet low in healthful carb sources like fruits and vegetables, but high in simple carbs like added sugar and white bread, it could take a toll on your health.

Diets high in foods rich in added sugar like candy, soda, and sugary cereals are especially problematic. High added sugar intake is linked to poor blood sugar control, high triglyceride levels, non-alcoholic fatty liver disease, and many other health conditions.

For overall health, you’ll want to limit your intake of added sugars and refined carbs that have been stripped of nutrients.

Refined Grains

Refined grain products like white rice, white bread, and snack foods like crackers are made with refined flour, which is low in nutrients like fiber and minerals.

Although having refined carbs once in a while won’t negatively impact health, the majority of the carbs in your diet should come from complex sources like vegetables, fruits, beans, and whole grains. 

Added Sugars

Table sugar, high-fructose corn syrup, honey, and other added sugars should be kept to a minimum for optimal health. 

The American Heart Association currently recommends that adult men and women should limit added sugar to no more than 9 teaspoons (38 grams) and no more than 6 teaspoons (25 grams) per day, respectively. However, many health experts suggest that added sugar should be limited even further to lower the risk of chronic diseases.

Sugary Foods and Beverages

Added sugar is found in a number of foods, even savory products. Candy, icing, cakes, cookies, and soda are some of the more obvious sources of added sugar, but yogurt, salad dressing, dipping sauces, and granola can pack just as much. 

Drinks like sweetened coffees, soda, and energy drinks are major sources of added sugar in most people’s diets.

In order to cut back on your intake of added sugar, try swapping out soda and energy drinks for sparkling water and reducing your intake of sugary foods like ice cream, candy, and sweetened yogurt.

A Quick Review 

Complex carbs are harder for your body to break down and cause a more gradual increase in blood sugar compared to simple carbs.

Foods rich in complex carbs like beans, vegetables, fruits, and whole grains are rich in fiber, vitamins, minerals, and other beneficial compounds that support your health. 

Swapping sources of simple carbs like soda, white bread, and sugary breakfast cereals with more nutritious complex carbs could help improve the quality of your diet and reduce your risk of a number of chronic diseases.