Person pouring milk over breakfast cereal while wondering about simple vs. complex carbs

Simple vs. Complex Carbs: How Are They Different?

Medically reviewed on Aug 7, 2023 by Jordan Stachel, M.S., RDN, CPT. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

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When you’re focused on improving your well-being, it can be challenging to sort through “no-carb,” “low-carb,” or “keto” diets that pledge to improve your health.

But the basics of nutrition are relatively straightforward. Three macronutrients comprise a healthy diet: fats, proteins, and carbohydrates. [1] Ideally, 45 to 65% of your daily energy needs will be fueled by carbs. [2] This category can be broken down further into two types: simple and complex carbohydrates. [1]

The easiest way to understand the difference between simple vs. complex carbs is that while simple carbohydrates are digested rapidly, complex carbohydrates take longer for your digestive system to process. [1] The paces of digestion can have various effects on how your body works. The following guide will explain these, as well as why complex carbohydrates are generally considered healthier.

Key Differences Between Simple and Complex Carbohydrates

Your body treats both simple and complex carbohydrates as its primary source of energy. [1] However, the traits and effects on the body differ in several domains [3]:

  • Chemical structure – Simple and complex carbohydrates are built differently on a molecular level. While simple carbohydrates, also known as ‘simple sugars’, are made of very few sugar molecules (usually one or two), complex carbohydrates have more molecules. Complex carbohydrates’ complicated chemical structure is why it takes the body more energy and time to process and digest them.
  • Effects on blood glucose – All carbohydrates, no matter what type they are, affect your blood sugar level. Because complex carbohydrates are digested more slowly, they tend to keep blood glucose (or blood sugar) more stable. Because simple carbohydrates are processed faster, they can cause blood glucose to spike abruptly (and later plummet). Over time, this can be stressful and even damaging to biological functioning.
  • Nutritional value – Complex carbohydrates are typically much more nutritionally dense than simple ones. Simple carbohydrates are often artificially refined, which means they’re stripped of the nutrients and fiber your body needs.

See related: Macronutrients vs. Micronutrients

Are Complex Carbohydrates Better than Simple Carbohydrates?

Both simple and complex carbohydrates can be a part of a healthy diet. However, eaten in excessive amounts, simple carbohydrates can cause:

  • Weight gain
  • Increased risk of diabetes
  • Increased risk of heart disease
  • Higher cholesterol

One of the primary drivers of obesity is a poor diet and a sedentary lifestyle.4 Consuming simple carbohydrates in excess can lead to weight gain and/or obesity. Excess weight and obesity can result in a cascade of related health risks, among them are type 2 diabetes and certain cancers. [4]

Simple vs. Complex Carbs in Diet

For most individuals, it’s possible to adhere to a diet that includes both complex carbohydrates and simple ones (once and a while). However, certain conditions like type 2 diabetes can make simple carbohydrates more risky to consume. [5]

If you’re not sure what types of carbohydrates you can include in your diet, it’s important to consult with a healthcare provider. [5] Learning how to identify between the two is the first step in empowering yourself to make the most supportive food choices possible.

Simple Carbohydrate Sources

Simple carbs are found in foods like table sugar, honey, fruit, and some refined grains. They also cause a quick blood sugar level spike. A good rule of thumb for spotting simple carbohydrates is to look for foods that are highly processed or manufactured. These include [3]:

  • Baked goods, like muffins, pastries, and cake
  • Sodas and fruit juices, especially those with added sugars
  • Candy and packaged sweets
  • Sugary cereals

If you’re trying to stay away from simple carbohydrates, it’s best to reduce your consumption of food with added sugars. Instead, opt for whole foods or high-fiber, low-carb foods that have been minimally processed.

Complex Carbohydrate Sources

The produce section (and some aisles) of the grocery store is the best place to stock up on whole, complex carbohydrates.3 These carbohydrates consist of multiple sugar molecules and are found in nutrient-dense foods like whole grains, legumes, vegetables, and some fruits.

Unlike simple carbs, complex carbs take longer to digest and break down into glucose. Look for starchy foods such as [3]:

  • Whole grains, like whole-wheat bread, whole-wheat pasta, brown rice, and oatmeal
  • Vegetables, like starchy vegetables such as squash or potatoes
  • Legumes and beans, like chickpeas, lentils, and black beans
  • Fruits, like melon, pears, apples, and berries are also a healthy choice. Just remember that they contain a fair amount of sugar, or simple carbohydrates. But because fruit also contains fiber, it takes longer to digest and therefore has a gentler effect on blood glucose levels than some other sugary foods.

Arriving at a diet that supports well-being, weight maintenance, and your preferences is highly personal. Some people can consume simple carbohydrate-based foods in moderation without harming their health.6 Others may be more prone to compulsive eating, which may cause health problems down the line. [6] A trusted healthcare provider can be an ally in deciding what boundaries to have around your carbohydrate consumption.

Make Informed Dietary Decisions With Everlywell

Understanding the differences between simple and complex carbohydrates allows you to determine the right carbs to make up a balanced diet. Making educated, empowered dietary choices feels more possible when you have a seasoned support network in your corner. Whether your goal is to lose weight or to optimize your body’s nutritional needs, Everlywell has the tools you can rely on to advance on your wellness journey.

From a Weight Care+ telehealth program to at-home tests that help you track your nutritional health, Everlywell is by your side, wherever your wellness journey leads. Find out more about your body’s unique needs by visiting Everlywell online today.

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  1. Cleveland Clinic. Carbohydrates. Cleveland Clinic. Published 2014. URL. Accessed Aug 4, 2023.
  2. Mayo Clinic Staff. Carbohydrates: How carbs fit into a healthy diet. Mayo Clinic. Published March 22, 2022. URL. Accessed Aug 4, 2023.
  3. Good vs. Bad Carbs: What Foods Should You Eat? (And Which Ones Should You Avoid?). Cleveland Clinic. Published March 18, 2022. URL. Accessed Aug 4, 2023.
  4. Obesity and Cancer. National Cancer Institute. Published 2011. URL. Accessed Aug 4, 2023.
  5. Why Are Certain Foods so Addictive? Cleveland Clinic. Published March 4, 2021. Accessed August 27, 2023. URL. Accessed Aug 4, 2023.
  6. Can You Eat Fruit If You Have Diabetes? Cleveland Clinic. Published June 4, 2019. URL. Accessed Aug 4, 2023.
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