Carbohydrates are often misunderstood, yet they are one of the body’s primary sources of energy and play an important role in physical performance, brain function, digestion, and overall health. However, not all carbohydrates affect the body in the same way; their nutritional value depends on their source, degree of processing, fiber content, and how quickly they influence blood sugar. Understanding the difference between complex and simple carbohydrates can help you make better food choices, maintain steady energy, support a healthy metabolism, and reach your fitness goals without unnecessarily eliminating an entire macronutrient.
Carbohydrates are one of the three essential macronutrients, along with protein and fat. Macronutrients are nutrients the body needs in large amounts to produce energy, support growth and development, and maintain healthy physiological function. This guide explores what carbohydrates are, their roles in the body, the different types of carbs, the healthiest sources, and how much you may need.
What Are Carbohydrates?
Carbohydrates are organic compounds made of carbon, hydrogen, and oxygen. During digestion, the body breaks most carbohydrates down into glucose, or blood sugar, which cells can use for immediate energy. Glucose that is not needed right away can be stored as glycogen in the liver and muscles for later use. Like protein, carbohydrates provide 4 calories per gram, while fat provides 9 calories per gram.
Carbohydrates are found in a wide variety of foods, including fruits, vegetables, grains, legumes, and dairy products, as well as bread, rice, pasta, and snack foods. However, not all carbohydrates affect the body in the same way. Fiber-rich, minimally processed carbohydrates generally digest more slowly, support satiety, and provide steadier energy. Refined and simple carbohydrates are typically digested more quickly, which can produce a rapid burst of energy followed by a drop in blood sugar and renewed hunger.
The Role of Carbs in the Body
These are multifaceted compounds that have multiple and diverse roles:
- Energy Production: The main function of carbohydrates is to provide energy to the body. When carbs are broken down into glucose and enter the bloodstream, they are taken up into your cells to produce a fuel molecule called adenosine triphosphate (ATP). ATP is used to power metabolic processes.
- Energy Storage: After glucose is used for immediate tasks, your body stores excess glucose for later use as glycogen. The liver stores approximately 100 grams of glycogen, and muscles can contain approximately 500 grams of glycogen. Liver glycogen can be released into the bloodstream to energize the body and help maintain normal blood sugar levels between meals. Muscle glycogen can only be used by muscle cells to assist during long periods of high-intensity exercise.
- Digestive Health: Fiber helps maintain healthy digestion and is divided into soluble and insoluble fiber. Soluble fiber (oats, legumes, fruits, and vegetables) draws in water and forms a gel-like substance while passing through the body, which increases the stool’s bulk of your stool, softens it, and facilitates bowel movements. Insoluble fiber (whole grains) adds bulk to your stools and increases bowel frequency.
- Cardiovascular Health: Carbs high in fiber help lower “bad” LDL cholesterol and decrease the risk of heart disease. Fiber binds to bile acids and prevents them from being reabsorbed. Then, the liver uses cholesterol to make more bile, which otherwise would be in the blood.
- Healthy Blood Sugar: Fiber delays carb absorption in the digestive tract, helping lower blood sugar levels post-meals.
Types of Carbohydrates?
Not all carbs are created equal. Understanding this powerful macronutrient can help you make better choices and instill changes to your health and fitness level. Carbohydrates are classified according to their degree of polymerization (number of macromolecules) and are divided into sugars, oligosaccharides and polysaccharides or sugars, fibers, and starches.
Simple Carbs
Simple carbs (monosaccharides and disaccharides) are made of sugars and consist of shorter molecules that digest more quickly than complex carbohydrates. Because of their shorter chains, they spike blood glucose and produce short-lasting spurts of energy. However, alertness reduces, and fatigue increases after 30 to 60 minutes of consuming them.
The following are some examples of simple carbs:
- Sugar, brown sugar, invert sugar
- Sucrose
- Candy
- Sugar drinks and sodas
- Syrup, high-fructose corn syrup, malt syrup, corn syrup
- Table sugar
- Fruit juice concentrate
- Sugary snacks
- Pastries
- Desserts
- Corn sweetener
- Dextrose
- Fruit juice concentrate
- Fructose
- Honey
- Lactose
- Maltose
- Molasses
Complex Carbs
Complex carbohydrates are polysaccharides (or oligosaccharides) and contain longer chains of sugar molecules. When it comes to complex carbs, they take longer to break down in the stomach and digest. They have less impact on blood sugar levels and are a more sustainable energy source.
- Starches: These complex carbs are made of lots of simple sugars strung together. Your body needs to break starches down into sugars to use them for energy. Starches include bread, cereal, potatoes, grains, and pasta. They also include certain vegetables, like potatoes, peas, pumpkin, corn, winter squash, and green peas.
- Fiber: This complex carbohydrate, but your body cannot break it down so easily. Carbs high in fiber can help you feel full longer and provide other health benefits. They can help prevent digestive problems, such as constipation, and lower cholesterol and blood sugar. Just make sure you check your carbohydrates to reduce the chance of contracting E. coli. Fiber is found in fruits, vegetables, legumes, and whole grains.
Best Carb Sources to Consume
There is no need to avoid carbs – your body needs them. You just need to choose the right carbohydrates to eat and eat them in the right amounts. You should try to avoid the regular consumption of simple carbs such as sugary drinks, sodas, fruit juices, and baked goods. At the same time, you should replace white flour products (white pasta, bread) and refined grain alternatives with whole grain or legume-based options.
As a general rule, you should try to consume complex carbs with your meals. They are moderate in calories, high in nutrients and natural fibers, low in sodium, and don’t have trans-fats or refined sugars. The following are some examples of complex carbohydrates to eat:
- Whole Grains: brown rice, wild rice, oatmeal, whole barley
- Grain-Like Foods: quinoa and buckwheat
- Starchy Vegetables: potatoes, sweet potatoes, and corn
- Non-Starchy Vegetables: asparagus and zucchini
- Legumes: beans, lentils, kidney beans, and chickpeas
How Many Carbs Do You Need?
Your carb intake depends on numerous factors, such as your age, sex, activity level, health, and goals. If you want to calculate your carb needs according to your biometrics and individual needs, check out a carb calculator. As a general rule, the Institute of Medicine recommends that you consume at least 130 grams of carbohydrates daily. Other sources recommended that carbohydrates encompass 45% to 65% of your daily calories, which equates to 225 to 325 grams of carbs if you eat 2,000 calories a day.
Studies show that low-carb diets have numerous benefits. These diets help induce rapid fat loss, creating big changes aesthetically. Low-carb diets help reduce appetite, leading people to eat fewer calories. Additionally, they can help lower blood sugar, blood pressure, and LDL (bad) cholesterol.
- Eating a low-carbohydrate diet (less than 26% carbohydrates or less than 130 gm/day) works for people who want to be leaner and more active, while staying healthy.
- Eating a very low-carbohydrate diet (less than 10% carbohydrates or less than 50 gm/day) works for those with fat loss goals and people who want to experience bigger metabolic effects. Since eating less than 50 grams of carbs per day allows your body to go into ketosis, the body’s energy is provided by ketone bodies, not carbs. This not only helps to lose body fat but also to regulate blood sugar, improve glycemic control, and markers of cardiometabolic risk factors.
One thing to keep in mind is that when you don’t consume a sufficient amount of carbs, fats are used for energy. However, if there are not enough calories being consumed, your body breaks down protein instead. This can lead to a catabolic state where the body eats its own muscle.
The Glycemic Index
We couldn’t talk about carbohydrates without mentioning the glycemic Index (GI). This is a scale that gives a number to carbohydrates, indicating how quickly a food causes a person’s blood sugar to rise. Foods high on the glycemic index can cause harmful blood sugar spikes and make it more challenging to maintain a healthy weight.
The GI scores are as follows:
- low GI foods: 55 or less
- medium GI foods: 56–69
- high GI foods: 70 or above
The Glycemic Index Foundation recommends that you aim for an average dietary GI score of 45. You don’t have to only eat foods with a GI score of 45 or lower, but balance the intake of higher GI foods by eating foods with a lower GI. However, if you have blood sugar problems, you should try to eat foods with a low glycemic index and avoid high GI foods.
You should also keep in mind several factors that can affect the GI:
- Cooking: Cooking foods for longer periods tends to raise GI – For instance, pasta cooked al dente has a lower GI than cooking it to the point of softness.
- Processing: Processing foods also raises GI – For example, commercial fruit juice has a higher GI than a whole fruit or a raw fresh juice.
- Ripping: Riper foods usually have a higher GI – A banana, for example, has a lower GI than a ripen banana.
- Pairing: Certain foods can affect GI – Fiber lowers the total GI of a meal.
Takeaway
As you can see, carbohydrates don’t have to be demonized. You don’t have to eat a super restrictive carb. When you eat a macronutrient in excess, whether it is carbs, fats, or proteins, your body stores it as fat. Carbs are not the enemy; they provide several functions that can help you accomplish your goals. At the end of the day, it’s essential to create an appropriate balance between the differing carbohydrates. A simple measure is consuming more complex carbohydrates regularly since they keep you fuller longer, give you longer-lasting energy, and reduce cravings. You can consume simple carbs occasionally. As long as you try to remain balanced, you will positively influence your aesthetics, your health, and experience results.
To a Fitter Healthier You,
Mind-Body Optimization Specialist
About the Author
Adriana Albritton is a Mind-Body Optimization Specialist and founder of FitnAll Coaching. She developed the FITNALL Method, a holistic framework that integrates fitness, internal health, thought patterns, nutrition, adaptation, longevity, and lifestyle habits to support sustainable fat loss and long-term wellness. Adriana is the author of 28 Days to a New Life: A Holistic Program to Get Fit, Delay Aging, and Enhance Your Mindset. She speaks and writes about holistic performance, longevity, and the integration of mind and body for optimal health.
