Simple vs Complex Carbohydrates - Understanding the Basics

What we eat greatly affects our energy, mood, and health. By understanding the differences between simple carbohydrates and complex carbohydrates, you’ll be better equipped to choose fuel that supports your adventures—whether you’re powering through a morning workout, tackling a busy day, or hitting the trail for your next hike. In this article, we’ll dive into the composition, function, and how carbs work in your body.

Not all carbohydrates are created equal, so knowing the basics of simple and complex carbohydrates—and how they influence your energy—will help you make smarter, more energized choices every day.

Dietary Carbohydrates

What Are Carbohydrates? Honestly, pause for a minute and think about this. You can probably come up with several examples of foods that fall in this category, but defining this naturally occurring compound might be a little challenging. So, let’s take it apart and see what makes up this macronutrient.

Carbohydrates are one of the three main macronutrients your body needs, along with proteins and fats. Carbohydrates are a group of organic compounds primarily made up of carbon, hydrogen, and oxygen atoms. The word carbohydrate can be broken down into “carbo”, meaning carbon, and “hydrate”, meaning water. Pretty cool, right?

There are three types of carbs in our diets as follows:¹

1. Complex carbs (starches)
2. Simple carbs (sugars)
3. Dietary Fiber

Simple enough, however there’s a little more digging we need to do to understand the simple and complex carbohydrates and how they are categorized.

Classifying Carbohydrates

There are 2 main categories of carbohydrates. These include simple and complex carbohydrates. Looking at how carbohydrates are arranged for each group can help us to understand the key differences between simple and complex carbohydrates.

This might sound familiar from science class, but no need to worry, we're going to recap the basics. And hey-it’s a good feeling to know that what you learned years ago may continue to serve you well today!

Simple Carbohydrates

Monosaccharides

Monosaccharides are the simplest form of carbohydrates. They consist of one, (hence-mono meaning one,) sugar unit and cannot be broken down into smaller sugars. The word "saccharide," which means sugar, is often used interchangeably with carbohydrate. Now let’s start looking at these simple carbohydrates, starting with the simplest unit known as a monosaccharide.

The three most common monosaccharides include:

• Glucose. Glucose as you know, is the primary source of energy for our cells. Cool fact —even bacteria, plants and animals use glucose as their fuel source!
• Fructose. This simple sugar is mostly found in fruits and honey. Fructose is also one of the most common simple sugars found in nature.
• Galactose. Galactose and glucose together form the natural dairy carbohydrate called lactose.

Disaccharides

Disaccharides are formed when two monosaccharides (or simple sugars) are joined together. Disaccharides include the following:

• Lactose. Lactose is made up of glucose and galactose as we noted above and is often referred to as “milk sugar.”
• Maltose. Two glucose molecules linked together form the disaccharide, maltose. Maltose is often referred to as malt sugar.
• Sucrose. We all know that sucrose is called table sugar, which is made of glucose and fructose.

Complex Carbohydrates

Now we are getting into carbs with a little more complexity in their structural makeup. Complex carbohydrates consist of three or more sugars (oligosaccharides or polysaccharides) linked together, forming a complex structure.

Basically, these are many chains of sugar molecules linked together, forming a long chain that requires our body to work harder to break them down for energy. Because they require a longer time for digestion, complex carbs have a different impact on your body. These carbohydrates give us a feeling of fullness, help promote healthy gut bacteria, and digestion.² Good sources of complex carbohydrates include whole grains like oats, brown rice, and quinoa, legumes such as beans and barley, to name a few.

There are two main groups of complex carbohydrates: starches and fibers.^3,4

• Starch. Starches are found in many plant-based foods. These include potatoes, corn, beans, bananas, rice, and grain products are some examples of starchy foods.^2,3
• Fiber. This includes both soluble and insoluble fiber. Both of these fibers play roles in supporting a healthy digestive system as well as supporting cardiovascular health and aiding in the management of healthy glucose and lipid (fat) metabolism.^2,3,5

Carbohydrates: A Reliable Energy Source

Carbohydrates serve as the body's primary energy source. When consumed, they are broken down into glucose, which is then used by cells for energy. The preferred energy source for the brain is glucose. Any glucose that is not readily used is stored as glycogen in the liver and muscles for later use. This backup reserve allows the body to tap into this stored energy source, especially when energy is needed for long-lasting activities or workouts.

The Impact Carbs Have on Blood Glucose

When you eat simple sugars, your blood glucose levels increase quickly. This may give you a short-lived feeling of energy kicking in. Though it may help to raise blood glucose levels, it often leads to a sudden drop afterward, and after that, it can leave you feeling tired and sluggish.

Your body signals insulin to handle these quick sugar spikes. Once your pancreas releases insulin, its job is to move from your blood into your cells. If you eat too many simple carbohydrates or sugars, your body might become less sensitive to insulin over time, leading to your insulin not working as efficiently as it should. Consuming excessive refined sugars, such as sweetened drinks, desserts, and other treats, can add extra calories and, over time, may lead to unhealthy weight gain.

Eating complex carbohydrates can lend to a slower rise in blood glucose levels, because these carbs require more time for the body to digest them.⁴ This demonstrates that they are less likely to cause sudden spikes in blood sugar, compared to simple sugars or carbohydrates. Also, a balanced or mixed meal that includes all of the macronutrients (carbohydrates, protein, and healthy fats) will also slow down the entry of glucose into the bloodstream.

Other Health Benefits of Dietary Fiber

Foods rich in soluble fiber, found in fiber-rich foods including oatmeal and apples, can help support healthy lipid metabolism. According to the Dietary Guidelines for Americans, 2020-2025, the average American only eats about 15 g of fiber per day. This falls short of the so-recommended 25 to 35 g of fiber per day.⁶

Slowly increasing your fiber intake may help to support healthy weight management.⁴ Don’t forget to increase your fluid intake, especially water, as you increase your dietary fiber.

Key Takeaways

After you’ve explored the differences between simple and complex carbohydrates, you can see that the quality of your carbohydrate choices can certainly be important to support optimal health.

Strive to prioritize whole, unprocessed complex carbohydrates. Focus on whole grains, legumes, organic fruits, and vegetables, and limit your intake of refined sugars and processed foods. Be mindful of portion sizes, even with healthy options.

Reach for our USDA-certified organic, farm fresh, cold-pressed Vive Organic Wellness Shots. Not only do they taste amazing, but there is also no sugar added — just an overall wellness boost!

Disclaimer: This blog contains promotional content about our products. The information provided in this blog is for educational and informational purposes only and should not be construed as medical advice. While the nutritional information and health tips shared here are based on published studies and expert insights, they should not replace advice and treatment from a healthcare professional. Always consult a qualified healthcare provider with any questions you may have regarding a medical condition or health objectives.

References

1. “Carbohydrates — Part of a Healthful Diabetes Diet.” Www.eatright.org, www.eatright.org/health/health-conditions/diabetes/carbohydrates-part-of-a-healthful-diabetes-diet . Accessed 20 July 2025.
2. Mora-Flores, Lorena P et al. “The Role of Carbohydrate Intake on the Gut Microbiome: A Weight of Evidence Systematic Review.” Microorganisms vol. 11,7 1728. 30 Jun. 2023, https://doi.org/10.3390/microorganisms11071728 .
3. Holesh, Julie E, et al. “Physiology, Carbohydrates.” National Library of Medicine, StatPearls Publishing, 2023, www.ncbi.nlm.nih.gov/books/NBK459280/ .
4. Younkin, Lainey. “What Is a Complex Carbohydrate?” EatingWell, 22 Nov. Accessed 20 July 2025.2017, www.eatingwell.com/article/290631/what-is-a-complex-carbohydrate/ . Accessed 20 July 2025.
5. Functional Medicine University. “Health Benefits of Soluble and Insoluble Fiber and Its Implication in Disease Prevention.” Functionalmedicineuniversity.com, Oct. 2023, www.functionalmedicineuniversity.com/public/2058.cfm.
6. U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition. December 2020. Available at DietaryGuidelines.gov. Accessed 20 July 2025.