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Get To Know Your Carbs: Complex Carbs Made Simple

complex carbohydrates

The quality of your carbs matters 

Are carbs a mystery for you? Did you know that even a small shift in your carb intake and quality can have a dramatic effect on your health goals? All carbs weren't created equal. But when you personalize the right carbs, at the right time, in the right amounts, you will begin to see the positive effect on your metabolic health. Let's dive into what types of carbs there are. 

Carbohydrates are essential nutrients the body needs to provide energy. However, it's important to note that the quality of your carbs matters because they significantly impact your metabolism. To find out your metabolic health, take our metabolic health quiz.

healthy carbshealthy carbs metabolic health

Once you understand the importance of consuming high-quality carbohydrates, you’ll know how to make informed decisions about your carb intake and start applying them to your diet. Let’s look at the basics of carbohydrates and how they function and affect your metabolic health.

What types of carbohydrates are there and why do they matter?

Carbohydrates are sugar molecules found in many foods we consume. They are also one of the three macronutrients the body needs to function properly. Carbohydrates are crucial for many reasons, including brain function and athletic performance, but specifically, they play a vital role in your metabolic function.

Consuming high-quality complex carbohydrates can help you manage weight, improve metabolism, and achieve overall health goals. This goes hand-in-hand with lifestyle factors such as ensuring you're also maintaining physical movement in your day and achieving at least 7-9 hours of sleep every night, and managing your stress and burnout. 

Carbohydrates and metabolism: How they work together

Carbs get a bad reputation in the dier world. Meanwhile, they are actually integral for metabolic flexibility. We want our bodies to be able to burn both fat and carbs and to do this, we need to make sure we’re consuming both.

Let’s discuss how carbohydrates and your metabolism work together. Metabolism refers to the chemical reactions in our body that convert food into energy. Carbohydrates play an important role in the human body. They act as an energy source, help control blood glucose and insulin levels, and participate in cholesterol and triglyceride metabolism (1). During digestion, carbohydrates are broken down into simple sugars known as glucose which are then used by your body as a primary source of energy to support your metabolism and other bodily functions.

Think about it this way: you need carbohydrates for energy production and optimal metabolism. Optimizing your metabolism with the right carbs can help you burn more fat, lose weight, and endure physical activity better. One cannot function without the other, and that’s why you should be consuming the right carbohydrates.

The different types of carbohydrates: Complex vs. Simple

Let’s discuss the different types of carbs, both complex and simple. Specifically, complex carbs are derived from whole and unprocessed plant-based foods, however, they can also be processed (refined) as well. They are considered healthier when compared to simple carbs - which are in high-processed, high-sugar foods and beverages. Increased consumption of simple carbs is a major driver in worldwide obesity and can lead to metabolic syndromes.

types of carbohydrates

Furthermore, these two types of carbohydrates generally fall into fast-absorbing (simple), and slow-absorbing (complex) carbs. Fast-absorbing carbs, like white bread, pasta, white rice, juice, sweets, give us instant satisfaction, but don't contain a lot of fiber.

Complex carbs comprise three or more sugars bonded in a more complex chemical structure. They are slow-absorbing and naturally take longer to digest to help you break through your weight loss plateau, and subsequently have a more gradual effect on increasing blood sugar levels. This "satisfied" feeling also helps prevent sugar spikes that lead to snacking and cravings - making them the healthier carbs to consume. By using real-time insights to understand your metabolic rate, you can make better choices.

"The combination of metabolic feedback and daily plans Lumen gives me a structure to work to enabling me to fuel the best for my daily requirements."
Maria, 52, England

Foods such as apples, broccoli, lentils, nuts, beans, and unrefined whole grains fall into the category of complex carbs, and are preferred for your metabolic and overall health. These nutrients are not only essential for energy, but they help your metabolism digest at a more sustainable rate. With a personalized meal plan, you won't have to guess which carbs fall into which category.  Let’s look closer at the effects simple and complex carbs have on your metabolic health.

How simple carbs are processed in the body

The reason that simple (fast-absorbing) carbohydrates harm your body and metabolic health is that they are quickly digested, causing your blood sugar to spike. Moreover, repeated spikes cause more food cravings, ushering you to overeat the same types of foods. The International Journal of Environmental and Public Health (1) found that obesity and being overweight, due to a diet high in excessive simple carbs, were leading risk factors for chronic diseases, including cardiovascular, musculoskeletal disorders, and cancers.

Additionally, consuming simple carbohydrates can lead to many other diseases and health issues, such as insulin resistance, type 2 diabetes, and other chronic illnesses (2). By comparison, another study (3) also noted that consuming excessively simple carbohydrates put people at risk of developing metabolic syndrome.

simple carbohydrates

Unfortunately, if diet changes are not made in time, you can get stuck in a detrimental cycle and put yourself at risk for many diseases.

"I got so much added value (other than weight loss) through the Lumen community. I have learned that I should not be working out as hard as I did. When I started eating more (of the right food) and exercising less the fat came off and I have more muscle and energy."
Deanna, 54, Mexico

However, learning how to increase your metabolic health with healthy eating and nutrition habits is the best way to combat these negatives.

The benefits of consuming high-quality carbohydrates

Consuming a diet of high-quality carbohydrates is beneficial for many reasons. For starters, complex carbs contain the minerals, vitamins, and nutrients your metabolism needs to perform at its optimal level.

These nutrients are important because it helps build optimal metabolic flexibility, increase energy levels, and significantly reduce the risk of long-term chronic illnesses and diseases. The Journal of Clinical Medicine (4) notes that a diet rich in fiber, which is found in complex carbs, reduces the chances of developing type 2 diabetes and other diseases as well as improves blood sugar levels.

complex carbs list

The major difference between complex and simple carbohydrates is that complex carbs are slowly broken down and processed at a much slower rate, helping your metabolism and body to build a more sustainable way to store and provide energy. This is why you need to know how to eat for your metabolism by building a personalized plan and tracking your progress.

Practical tips for incorporating more high-quality carbohydrates into your diet

Now that you understand what complex and simple carbs are and how they affect your metabolism, here are a few tips our Lumen experts recommend.

To increase your intake of complex carbohydrates you should:

  • Create a plan: Integrating a healthy weekly meal plan based on your required carb intake that is suited to your metabolism.
  • Select healthier options: As you plan your week, make a grocery shopping list that includes quality and high-dense carbohydrates such as grains, vegetables, and foods.
  • Track your progress: Tracking your progress makes you accountable for your food choices. Additionally, you can identify what works for you and make a personalized plan. That way, you’ll be able to measure success and stay motivated.
  • Stay consistent: Eating habits don’t happen overnight, but staying consistent will help you stay on track toward your health goals. If you need ideas for nutritional meals that include carbs, you can get started with this healthy food list.

Incorporating Smart Carb Cycling

Did you know that by fluctuating your carb intake from day to day or strategically around activities like exercise, your body becomes more efficient at using carbs for energy, and contributes to metabolic flexibility?

Now that you have a better grip on the types of carbs - the carb cycling diet is an effective way to help you boost your metabolism, burn fat, and reach your weight-loss goals, along with several other potential benefits. With a personalized nutrition plan that can tie your dietary needs to your metabolism - you will be able to determine when your body needs a low, medium, or high-carb day - and which carbs to turn to to help you get there.


High-quality carbs are critical for optimal health. Consuming the right foods rich in fiber, minerals, and nutrients your body and metabolism need will decrease long-term chronic illnesses and diseases. The goal is to maximize your metabolic flexibility, lose weight, and improve your overall health.

Don’t wait. Incorporate high-quality carbs into your diet this week. With many resources like recommended / personalized nutrition plans, real-time insights into what your body is burning, pre and post-workout meals, and food requirements, you can be on your way to a better and healthier you.

Remember, it’s not about perfection, it's about progress. Have patience, be kind to yourself, and live a healthier and happier lifestyle.


  1. Holesh JE, Aslam S, Martin A. Physiology, Carbohydrates. [Updated 2022 Jul 25]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK459280/
  2. Clemente-Suárez VJ, Mielgo-Ayuso J, Martín-Rodríguez A, Ramos-Campo DJ, Redondo-Flórez L, Tornero-Aguilera JF. The Burden of Carbohydrates in Health and Disease. Nutrients. 2022 Sep 15;14(18):3809. doi: 10.3390/nu14183809. PMID: 36145184; PMCID: PMC9505863.
  3. Ferretti F, Mariani M. Simple vs. Complex Carbohydrate Dietary Patterns and the Global Overweight and Obesity Pandemic. Int J Environ Res Public Health. 2017 Oct 4;14(10):1174. doi: 10.3390/ijerph14101174. PMID: 28976929; PMCID: PMC5664675.
  4. Hoyas I, Leon-Sanz M. Nutritional Challenges in Metabolic Syndrome. J Clin Med. 2019 Aug 24;8(9):1301. doi: 10.3390/jcm8091301. PMID: 31450565; PMCID: PMC6780536.

Lumen Editorial Desk & Reviewed by: Marine Melamed, R.D. Nutrition at Lumen

Marine is a registered dietitian with a passion for well-being, health and metabolism. She started her career as a clinical dietitian, opened her private practice to accompany patients from various backgrounds in their health journey, and is now providing nutrition support for Lumen’s customers.