When it comes to health and fitness, there is a lot of bad advice out there. There are two common misconceptions about body composition and diet:

• Decrease carbohydrates for weight loss

• Only increase protein for muscle growth

However, carbohydrates play a crucial role in muscle growth, workout performance, and recovery that's hard to replicate with other macros alone. While protein gets the spotlight, carbs are the unsung hero working behind the scenes to fuel your lifts, preserve muscle tissue, and optimize the hormonal environment your body needs to grow.

Let's dig into the science, the strategy, and what actually happens inside your muscles when you prioritize, or skip, carbs.

Why You Need Carbs for Building Muscle?

Think about it: building anything takes a lot of time, energy and resources. Building muscle is no different. The body requires a lot of energy to power through workouts that result in bigger, stronger muscles. Where does the body get most of that energy? Usually from carbs.

Here's how they directly support your gains:

Carbs are a long-term energy source

Out of all the energy sources for the human body, researchers have found that carbohydrates are the main source of energy in the human diet. And you can't build muscle if you can't perform in the gym. And performance is directly tied to energy availability.

Carbs provide quick, efficient fuel for high-intensity activities like lifting weights. Fat and protein can supply energy too, but they're slower to mobilize and less effective for explosive, anaerobic efforts. If you've ever tried a heavy squat session on a low-carb diet, you know the difference. Your muscles feel flat, your strength drops, and your endurance tanks.

Adequate carb intake ensures you can train hard, maintain volume, and push for progressive overload week after week, all critical for muscle growth.

Carbs help regulate muscle glycogen repletion

Glycogen is a stored carbohydrate in your muscles and liver, and it's your body's preferred fuel during intense exercise. When you lift weights, especially during high-volume or high-intensity sessions, your muscles burn through glycogen fast.

After your workout, your body needs to replenish those glycogen stores. Consuming carbs post-workout (and throughout the day) ensures your muscles are fully stocked and ready for the next session. If glycogen levels stay chronically low, your performance suffers, and so does your ability to progressively overload.

Carbs prevent muscle degradation

When carbohydrate intake is too low, your body starts looking for alternative fuel sources. And guess what's on the menu? Your muscle tissue.

In the absence of adequate carbs, your body can break down amino acids from muscle protein through a process called gluconeogenesis to create glucose for energy. This is especially true during prolonged or intense training sessions.  

A Netherlands study compared a low-carb diet to other diets and found that restricting carbs results in protein loss. By keeping carb intake adequate, you provide your body with readily available energy, sparing your muscle protein for what it's meant to do: repair and grow.

Carbs help muscles recover from exercise

The role that carbs play in recovery goes back to glycogen stores. Immediately after exercise, athletes need to replenish their glycogen stores in order to prevent glycogen depletion.

Glycogen depletion, when glycogen stores have run out, causes gluconeogenesis. This is when the body forms glucose from new sources to compensate for the lack of glucose from carbohydrates. When this happens, the body turns to sources like fat and protein to fill this need. Protein acts as the last line of defense when energy is required, meaning that energy accessibility is running very low. 

When the body breaks down protein to make more glucose, it takes from the muscle, causing them to waste away. Replenishing glycogen stores with complex carbs is important to prevent protein breakdown and muscle wasting.

Carbs promote hormonal balance for muscle growth

Carbs don't just fuel your muscles, they influence your hormones, too. Specifically, they help maintain healthy levels of testosterone and thyroid hormones, both of which are essential for muscle building and metabolic health.

Chronic low-carb intake, especially when combined with intense training, can suppress testosterone and elevate cortisol. High cortisol is catabolic, meaning it promotes muscle breakdown and fat storage, particularly around the midsection.

On the flip side, consuming enough carbs helps keep cortisol in check and supports an anabolic hormonal environment. This balance is especially important if you're training frequently or in a calorie deficit.

Carbs enhance hydration and electrolyte balance

Carbohydrates play a big role in maintaining hydration status and electrolyte balance during exercise. This happens because glycogen binds to water in the body.  

During exercise, muscle cells are not only working hard but also dehydrating from the energy demands. When carbs are stored as glycogen, the body retains water along with it. This water retention within muscle fibers helps to maintain the electrolyte balance needed for proper muscle contraction and function. Without adequate carbs, muscles can become dehydrated, leading to premature fatigue, cramps, and suboptimal performance.

Carbs improve mental focus and motivation

Carbs not only fuel your muscles but also support mental energy, focus, and motivation. When you’re training hard, mental focus can sometimes slip if your body is energy-deprived. 

Since glucose is the brain’s primary fuel source, having sufficient carbs ensures that your mental faculties stay strong throughout your workout. Low-carb states can result in brain fog, poor concentration, and reduced mental stamina, which can make it harder to push through tough sessions.

How Many Carbs Should You Eat Per Day to Build Muscle?

So how many carbs do you actually need? The answer depends on your body weight, training intensity, and overall goals, but here's a general framework.

For most people focused on building muscle, aim for 3 to 5 grams of carbs per kilogram of body weight per day. If you're training intensely (lifting 5-6 days a week, doing high-volume sessions), you might need closer to 5-7 grams per kilogram.

Generally, very low carb consumption (<5%) is used for weight loss, while adequate carb consumption (55-60%) is used for muscle gain. 

Timing matters too. Prioritize carbs around your workouts, before for energy, and after for recovery. The rest can be spread throughout the day to maintain steady energy levels and support overall metabolic function.

Complex Carbs 

Complex carbohydrates should make up the bulk of your intake. These are digested more slowly, providing sustained energy and stable blood sugar levels. They're also packed with fiber, vitamins, and minerals that support overall health.

Great sources include:

• Oats

• Brown rice

• Quinoa

• Sweet potatoes

• Whole grain bread and pasta

• Legumes (beans, lentils)

These foods keep you full, support digestion, and fuel long training sessions without the crash that comes from simple sugars.

Simple Carbs

Simple carbs get a bad rap, but they have their place, especially around workouts. Because they're absorbed quickly, they're ideal for providing immediate energy before a session or rapidly replenishing glycogen afterward.

Good options include:

• Fruit (bananas, berries, apples)

• White rice

• Rice cakes

• Honey

• Sports drinks or dextrose powder (post-workout)

The key is context. Simple carbs are useful when you need fast fuel, but they shouldn't dominate your diet. Balance is everything.

What Happens to Muscle When Carbs are Low?

When you drastically cut carbs, especially while training hard, your body enters survival mode. And muscle growth? That's not a priority when your body is scrambling for fuel.

Now that we know how important carbs are to build muscle, let’s discuss some of the possibilities when carbs are restricted:

• Muscle Breakdown for Fuel: When carbs are insufficient, your body turns to protein for energy. It breaks down muscle tissue to access amino acids, which are then converted into glucose via gluconeogenesis. This process can lead to muscle wasting if carbs aren’t available to fuel your workouts.
  
  
  

• Decreased Performance: Carbs are the body’s main energy source during high-intensity exercise. When glycogen stores are low, muscle strength decreases, and fatigue sets in quicker. 
  
  
  

• Slower Recovery: Post-workout recovery is heavily dependent on glycogen replenishment. Without sufficient carbs, glycogen stores remain depleted, slowing down muscle recovery and prolonging muscle soreness. This leads to slower repair of muscle tissue, delaying the ability to push hard in future workouts.
  
  
  

• Impaired Muscle Growth: Since carbs support protein sparing, a lack of carbs forces the body to rely more on protein for energy, which can stunt muscle growth. 

Key Takeaways

You don't technically need carbs to build muscle, but they significantly improve workout performance, recovery, and muscle growth efficiency.

• Carbohydrates replenish muscle glycogen stores after training, which is essential for sustained performance and progressive overload.

• Adequate carb intake prevents muscle breakdown by providing readily available energy, sparing protein for muscle repair and growth.

• Aim for 3 to 5 grams of carbs per kilogram of body weight daily to build muscle, with higher amounts needed for intense training schedules.

• Carbs support an anabolic hormonal environment by maintaining healthy testosterone levels and keeping cortisol in check.

• Prioritize complex carbs like oats, sweet potatoes, and brown rice for sustained energy, and use simple carbs like fruit strategically around workouts.

FAQs

Isn't protein more important than carbs for building muscle?

Protein is absolutely critical, it provides the building blocks (amino acids) your muscles need to repair and grow. But carbs are what allow you to train hard enough to stimulate growth in the first place, and they create the metabolic environment for protein to do its job effectively.

Think of it this way: protein is the construction material, but carbs are the energy and workforce that make construction possible. You need both. Prioritizing one at the expense of the other will limit your results. A well-rounded muscle-building diet includes adequate protein (roughly 1.6–2.2 grams per kilogram of body weight) and sufficient carbs to fuel performance and recovery.

Do you need carbs to build muscle effectively?

While technically not required, carbs significantly enhance muscle growth by fueling intense workouts, replenishing glycogen stores, preventing muscle breakdown, and supporting hormonal balance. Building muscle without adequate carbs is slower and less efficient.

When is the best time to eat carbs for muscle building?

Prioritize carbs around your workouts - before training for energy and after for glycogen replenishment and recovery. Post-workout carbs paired with protein optimize insulin response, shuttling nutrients into muscles for repair and growth.

Can you build muscle on a low-carb or keto diet?

Yes, but muscle growth is typically slower and requires careful planning. Low-carb diets can compromise workout performance, reduce glycogen availability, and create hormonal imbalances that make muscle building less efficient than moderate-to-high carb approaches.

Are simple carbs or complex carbs better for building muscle?

Both serve different purposes. Complex carbs like oats and sweet potatoes provide sustained energy and should form your dietary foundation, while simple carbs like fruit and white rice are ideal around workouts for quick fuel and rapid glycogen replenishment.

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Lacey Bourassa is a health and wellness writer in Southern California. Her areas of expertise include weight loss, nutrition, and skin health. She attributes her passion for healthy living to her plant-based diet. You can find out more about Lacey at WrittenByLacey.com.

If you’ve ever heard someone talking about “macros,” they’re talking about three major nutrients: protein, fat, and carbohydrates.

Bodybuilders and fitness experts pay close attention to the macronutrient profile of the foods they eat to yield certain results—increased protein for muscle development and reduced carbohydrates for fat loss are some common examples of dietary targets.

By changing one’s macronutrient balance (i.e. a person on a high-fat diet gets most of his or her calories from overt fats, or foods rich in fats such as nuts and avocados), you can fuel your body with foods that will get you one step closer to your specific goals. Depending on whether your body composition goals are to gain muscle, lose weight, etc., you may give preference to one macro over the others.

Out of the three macros, one is often considered the least popular—carbohydrates or “carbs.” This is because comfort foods like pasta, bread, and cereal are high in carbs, and they’re linked to gaining weight. However, fruits and vegetables are also forms of carbs, and even at face value, you can see that based on this, not all carbs are created equal.

Do carbohydrates and body composition go hand in hand? Consuming a lot of carb-rich foods doesn’t automatically mean you’re going to gain weight. It all depends on the type you’re eating. However, cutting carbs does not necessarily mean that you will lose fat either.

People have long adopted high-protein diets to preserve lean body mass and high-fat, low-carb diets for weight loss, but high-carb diets are on the rise to achieve similar body composition results.

Different Types of Carbohydrates

There’s a stark difference between cookies and quinoa, yet both are classified as carbohydrates. The same thing goes for white bread and potatoes—both are carbs, but they’re vastly different in terms of nutritional content and overall effect on the body.

These different types of carbs have names: the type with a less complex structure is called a simple carbohydrate, including glucose, sucrose (table sugar), and fructose (from fruits) but starchy foods (potatoes, rice, etc.) and unprocessed plant-based foods are called complex carbohydrates. The next question is whether one is automatically better- the answer would appear to be complex carbs (as we’ll explain shortly) but the simple answer is no because even complex carbohydrates can be processed into less healthy versions, known as refined carbohydrates.

Carbs are often categorized as  “good carbs” or “bad carbs” but it isn’t that simple. The important thing to know about carbs is how they’re processed by the body. This helps us to understand how they affect body composition differently so that we can properly use carbohydrates to help us meet our goals.

Simple Carbohydrates

White flour and table sugar are examples of simple carbs. You might not recognize a simple carb when you see one, but if you’re looking at simple carbs on a molecular level, it is clear- simple carbs are made up of only 1 or 2 sugar molecules (while complex carbs have 3+ molecules bound together, hence the name complex).

Now the sugar in fruit isn’t quite the same as table sugar, but both fruit and white sugar are examples of simple carbs. While most simple carbs are what get called  “bad carbs”, they can actually provide significant benefits. Some simple carbs, like fruit, are packed with vitamins and minerals, providing you with high nutrient content. However, it is important to keep in mind that fruits are a bit of an exception in the simple carbohydrate category.

Consuming simple carbs gives you a readily available, quick source of energy. This is why major athletes sometimes consume candy right before a game, match, training session, or other performance events they want a rush of energy to power them through their physical endurance.

Simple carbs spike blood sugar levels, which can be dangerous and is a no-go for diabetics if intake is not monitored properly. The reason for this is this spike in blood sugar helps feed the body with glucose but will also cause the body to crash once this source of energy is used and glucose levels get low.

While a burst of energy may seem tempting, simple carbs have their drawbacks:

• Simple carbs are generally low in nutritional value. Despite being high in carbohydrates, they’re low in essential vitamins and minerals. It is important to check the nutrition facts when choosing simple carbs.

• When you consume simple carbs, you don’t stay full for long because they’re quickly digested. This can lead to binge eating because simple carbs aren’t satiating.

• The consumption of simple carbs is also linked to serious health problems, including increased risk of coronary heart disease and a higher risk of type 2 diabetes.

• Simple carbs can also be high in calories, which is not ideal for weight loss.

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Intake of simple carbs, with the exception of fruit, should be limited, as they can hinder your body composition goals and lead to serious health problems.

Refined Carbohydrates

Refined carbohydrates fall under the umbrella of simple carbohydrates in that they may be less beneficial to overall health. By processing carbs, you change their molecular structure and get refined carbs, which include chips, white bread, muffins, donuts, etc. By changing their structure these foods last longer, which makes them easier to mass produce and sell (think fast food).

The sugar in refined carbs is linked to chronic diseases and high body weight, including:

• Increased blood sugar and insulin resistance

• Weight gain and greater risk of type 2 diabetes

• Increased risk of cardiovascular disease

It’s easy to fall into the routine of having donuts for breakfast, chips at lunch, and white bread at dinner, but refined carbs like these are giving all carbohydrates a bad name because of their effects on the body.

Complex Carbohydrates

On the other end of the carb spectrum lies complex carbohydrates. Unlike simple carbs, where the molecular structure consists of single sugar molecules, complex carbs are made of sugar molecules strung together on a chain. Whole grains, legumes, vegetables, and other whole and unprocessed plant-based foods are examples of complex carbs.

Complex carbs are broken down into starch and fiber, which are each processed by the body in a unique way.

The digestion process actually starts in your mouth: saliva mixes with the complex carbs, engulfs them, and a digestive enzyme called amylase turns them into a type of simple carb called maltose, which can form either in the mouth or once it reaches the small intestine. The maltose continues through the digestive tract until digestive enzymes turn it into glucose, which is then absorbed into the bloodstream.

From there, the complex carbs are processed similarly to simple carbs—as in they’re converted to a simple form to be used for energy—but this process is significantly slower. The slow increase in blood sugar level triggers the pancreas to produce a hormone called insulin, so the sugar can be stored or used as a source of energy.

The fiber in complex carbs isn’t broken down into glucose molecules, however. Fiber stays intact as it travels through the digestive system, but the two types of fiber have different roles: soluble fiber attracts water and allows the intestines to absorb nutrients, and insoluble fiber speeds up digestion. Both are necessary for a healthy digestive tract.

The way that complex carbohydrates are processed contributes to the main benefits of consuming complex carbs:

• Complex carbs are digested slowly, giving you a feeling of satiety, allowing you to feel fuller for longer.

• The slow digestion also sustains energy, instead of spiking and crashing like simple sugars. Complex carbs encourage steady energy levels.

• The starch content in complex carbs are nutrient-dense, which means they’re full of vitamins and minerals.

• Complex carbs are also high in fiber, which promotes healthy digestion and absorption of the nutrients.

You don’t have to be scared of all carbs when it comes to body composition. Simple and refined carbs should be limited, but complex carbohydrates are nutrient-dense and beneficial to the body.

Low-Carb vs. High Complex Carb Diets for Weight Loss

Understanding what we know now about the types of carbs and how they are utilized in the body, it is clear that there are a lot of complexities to planning your carbohydrate intake.

When it comes to diets that are best for losing weight, your mind may automatically jump to low-carb diets. For decades, low-carb diets like Atkins, paleo, and keto diets have been at the forefront of weight loss regimens.

Low-carb diets are effective for quick weight loss, but are they sustainable for long-term weight loss? The safety and effectiveness of low-carb diets have come into question, especially as high complex carb diets like vegetarianism, veganism, and the Mediterranean diet become more popular.

Weight Loss on a Low-Carb Diet

Because carbs are restricted on these diets, the body is forced to burn fat as a source of energy, so the weight loss can be driven by a loss of fat mass.

While low-carb diets are beneficial for weight loss purposes, lower carb diets aren’t encouraged for long-term use and are often associated with serious health complications.

Ultimately, more data is needed to recommend the long-term safety and health benefits of low-carb diets.

In regards to low-carb diets and body composition, low-carb consumption has a direct connection to muscle mass. Glycogen stores account for the primary energy source that muscle groups use to provide energy. When carbs are reduced, muscle glycogen concentration is also reduced, decreasing energy stores. This is also why bodybuilders tend to avoid low-carb diets as they can hinder their ability to maximize their workouts.

Weight Loss on a High Complex Carb Diet

The Mediterranean diet has long been accredited for effective weight loss results, and now other high complex carb diets, such as whole food plant-based diets, are gaining traction for efficient weight loss. The key is getting your carbs from complex carbohydrates in their whole food form and reduce intake of simple sugars or refined carbs.

A diet with 40-65% of calories coming from carbohydrates is considered normal, so if you’re consuming the Standard American Diet, you might be consuming more than half your calories without realizing it.

High-carb diets are associated with a naturally lower intake of calories, which is crucial for weight loss. A moderate consumption of carbohydrates (47-64%) has been related to a lesser likelihood of being overweight or obese in healthy adults.

Maintaining a calorie deficit is easy on a high complex carb diet because whole plant-based foods are generally high in volume yet lower in calories, allowing you to consume large yet low-calorie portions. Complex carbs like potatoes, legumes, and grains don’t spike your blood sugar like simple carbs, so you won’t experience the crash and cravings as with other carbs.

Weight loss on a high complex carb diet isn’t as dramatic as it is on a low-carb diet. However, gradual weight loss is generally thought to be healthier and more sustainable. Additionally, slower weight loss means a greater likelihood that the weight lost will come from fat instead of muscle mass.

Contrary to popular belief, carbohydrates can be weight loss powerhouses if the right types are consumed. While structuring a diet truly requires guidance from a professional, it is likely that they will recommend a diet that promotes better health:

• A whole foods plant-based diet high in complex carbs can prevent, treat, and reverse coronary heart disease

• When whole grains are the main source of complex carbs in a well-rounded diet, cardiovascular disease and stroke can be prevented

• Type 2 diabetes can be prevented and treated with a diet high in fiber from complex carbs, such as legumes, whole grains, and starchy vegetables

• A plant-based diet high in complex carbs can also aid in obesity prevention and treatment as they tend to be associated with having a lower Body Mass Index

Not only is weight loss possible on a high complex carb diet, but carbohydrates are necessary for sustainable weight loss. When it comes to body composition, complex carbs make it easy to decrease calories while having the energy to burn more calories through exercise. Plus, diets high in complex carbs are sustainable long-term and have many proven health benefits.

Carbohydrates Are Not the Enemy of Body Composition

USDA recommendations stipulate that 45-65% of calories should come from carbohydrates in all age groups. While this is a general recommendation and not a steadfast rule, having most of your carbohydrate calorie allotment come from complex carbs can be part of a healthy, well-rounded diet, especially for people whose body composition goals include weight loss.

The “bad” carbs that give all carbs a bad name have a poor reputation because they’re typically highly processed and have added sugars and flours. Simple and refined carbs aren’t good for weight loss and they aren’t health-promoting foods, but complex carbs shouldn’t be brought down with them. When the right kind are consumed in the right quantities, you can promote your overall health and a healthy body composition.

Maintain a Balanced Diet

Opting for a diet that’s higher or lower in one macronutrient may yield the body composition results you want, but maintaining a balanced diet is important in any restriction diet. Even in low-carb diets, you still consume some forms of carbohydrates, so make sure they’re complex. In high-carb diets, stick to starchy carbs and low-calorie, plant-based carbohydrates so unhealthy weight gain isn’t an issue.

So are carbs really bad for body composition? It depends on the type you’re consuming. Weight loss on a high-carb diet of sweets, chips, and white bread isn’t nearly as plausible as weight loss on a high complex carb diet of whole grains, legumes, and starchy vegetables. When you’re getting the right kind of carbs, changing your body composition is possible. This is because complex carbs boost your energy for exercise and keep you fuller for longer.

So move over, simple carbs, because complex carbohydrates are here to set the record straight.

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Lacey Bourassa is a health and wellness writer in Southern California. Her areas of expertise include weight loss, nutrition, and skin health. She attributes her passion for healthy living to her plant-based diet. You can find out more about Lacey at WrittenByLacey.com.

Think of your favorite cheat day meals.

For some, it’s thick-crust pizza.  Or grandma’s rich, warm, and cheese-filled lasagna. Maybe for you it’s chocolate chip cookies?

All of these awesome foods are united by one thing: they’re all super heavy on carbohydrates (aka carbs). And since they’re supposedly bad for you, they’re often relegated to the ranks of cheat day meals.

However, as with fat, not all carbohydrates are created equal.

While carbohydrates have gotten a bad rap lately because they are presumably fattening and unhealthy, some cultures with high-carb intake don’t have the same high obesity rates as the U.S. – where one-third of adults (and 17 percent of children) are obese. This is in contrast to Japan where white rice and noodles are dietary staples.

What are we to make of this? Are carbs truly evil? Or should you embrace more carbs in your life?

In this article, we’ll take a close look at carbohydrates — their essential bodily functions, several established facts and hypotheses on whether they are friend or foe, and how eating the right carbs can contribute to a healthy weight and body composition.

Know Thy Carb: The Basics

Carbohydrates are one of the three macronutrients (the other two are protein and fat) that your body needs to maintain optimum health and other essential body functions. Macronutrients provide calories, which in turn supply energy.

Of the three macronutrients, carbohydrates act as the main source of energy because they are easily broken down into sugar (glucose to be specific) once they reach your bloodstream and are then transported to cells, tissues, and organs. Think of glucose as fuel.

Carbohydrate sources range from fruits and vegetables to soft drinks and cinnamon buns.

Furthermore, carbohydrates are further classified into two types:

• Simple carbohydrates

A simple carbohydrate can either be a monosaccharide or disaccharide. They are quickly absorbed into your bloodstream for instant energy because of their simple molecular structure. Think milk, honey, fruit juices, and table sugar.

• Complex carbohydrates

On the other hand, complex carbohydrates or starches have long chains of molecules and are also referred to as polysaccharides. These carbs take longer for the body to break down into glucose because of their more complex molecular composition.

Grains such as bread, rice, quinoa, and pasta are examples of complex carbs. Starchy vegetables like potatoes, sweet potatoes, peas, corn, and winter squash fall in the same category.

Carbs in Action

As carbs from the lasagna you eat are broken down by digestive enzymes, the amount of sugar (glucose) in your bloodstream increases. This has an impact on your blood sugar levels.

To help manage the sudden spike of blood sugar levels after your cheat day meal, the pancreas takes action by producing the hormone insulin. Insulin facilitates the transport and storage of the energy-boosting glucose to cells as well as to organs that store it — your skeletal muscles and liver.

Once your blood sugar returns to baseline levels as glucose is absorbed in the body, the pancreas will start producing glucagon instead of insulin. Glucagon tells your liver to let go of the stored sugar. This typically happens in between meals.

What if you’re eating too much carbs that is way more than your glucose-storing organs can handle?

There will be frequent outbursts of insulin production by the pancreas. Cells will be less sensitive to insulin and will eventually stop responding to high blood sugar levels. Think of this as your cells ignoring insulin’s pleas to take more glucose from the bloodstream. This is what happens in individuals with Type 2 diabetes or insulin resistance.

In some cases, the insulin-producing cells in your pancreas can’t keep up with the persistently high blood sugar levels and will quit producing insulin altogether.

Carb Consumption = Weight Gain: Myth or Fact?

It’s a myth.

People tend to believe that carbohydrates will make them fat because it spikes insulin levels.

What most people fail to realize is that insulin resistance itself isn’t directly or solely responsible for weight gain. More often than not, it’s the lack of physical activity that’s to blame.

Remember how your skeletal muscles store glucose?

Due to inactivity and failure to use up existing glucose reserves, the skeletal muscles will refuse to accept newer supplies of glucose from the carbs you chowed down recently. As a result, insulin will take the excess glucose to your liver.

What happens if the liver has already reached its maximum capacity of glucose reserves?

It produces triglycerides that are stored as fat. However, this doesn’t mean that you will directly gain weight if you eat carbs. Instead, caloric excess and lack of physical activity are the true culprits.

Not convinced?

Consider the extreme example of the New Guinea highland tribe at Tukisenta. It was found out that they consumed 94 percent of their dietary needs from carbohydrates, mainly from sweet potatoes. Yet they were mostly lean and fit, and exhibited no signs of protein deficiency.

In addition, a 2015 study whose findings are published in Cell Metabolism reveals that if you want to lose body fat, the amount of calories you consume will matter more than your carbohydrate consumption.

Such findings also confirmed the results of a  trial nearly three decades ago — specific macronutrient restriction doesn’t directly influence weight loss. As for going low-carb or high-carb, it turns out that neither offered significant weight loss changes over a 12-week period.

To further help you understand why carbs do not cause weight gain per se and not all carbs are created equal,  these two related concepts are worth examining:

• De novo lipogenesis

Remember how the carbs you consume are absorbed by trillions of cells in your body as well as your skeletal muscles and liver?

Once your cells, liver, and skeletal muscles reach their maximum glycogen storage capacity ( roughly 300-500 grams for skeletal muscles and about 100 grams for the liver), excess glucose is converted into fat through a processed called de novo lipogenesis.

But here’s the catch: it turns out that de novo lipogenesis exerts little influence in terms of significant weight gain, particularly if your excess carb consumption is preceded with exercise and carb restriction (which explains why intermittent fasting works for others).

• The Glycemic Index

Not all carbs are created equal, and some have a greater effect on your insulin levels than others. For people with diabetes or insulin resistance, this is particularly important.

A food’s Glycemic Index (ranging from 0 to 100) indicates how a certain carbohydrate will affect your blood sugar and insulin levels. Foods that digest quickly are high on the index, while those that digest slowly are lower on the index.

Foods that are high on the GI scale, like potatoes and white bread, are quickly broken down. This is what happens when you go through an abrupt sugar rush but eventually crash down minutes later. Foods with a low GI, like sweet potatoes and whole oats, are digested gradually, resulting to a more predictable, steady rise in blood sugar levels.

A food’s rank in the GI scale may be influenced by the following factors:

• Food processing – The more processed the food, the higher the GI. All the more reason to opt for whole carb sources.

• Fat and acid content of the food – Foods high in fat and acid or carbs eaten with fat or acid tend to have lower GI.

• Fiber content – Fiber slows down the rate of digestion, leading to a more gradual rise in blood sugar levels.

• Ripeness – Ripened fruits tend to have higher GI than their unripened counterparts.

While it has been shown in a 2014 study that foods with low GI tend to have anti-inflammatory benefits, it worth noting that the Glycemic Index has limitations too. In measuring a food’s GI, researchers tend to isolate the type of food that they feed their subjects within laboratory walls.  Yet within real life context,  these foods are often eaten in combination with each other.

In addition, just because the GI value of a certain food is low doesn’t necessarily mean that you have an excuse to go on a binge. Foods with a low GI aren’t automatically healthy. For example, pizza (Pizza Hut Super Supreme) has a GI of 36 while quinoa has 53. But quinoa has clearly more nutritional value than Pizza Hut’s Super Supreme pizza. Plus, you’re more likely to binge on pizza (more calories!) than quinoa.

If you’re interested in finding out which foods you eat may have high GI scores, you can take a look at the University of Sydney’s GI database to check the glycemic index of a wide variety of foods.

Your Action Plan

So should you give up carbs for weight loss? Difficult to say.

Although low-carb diets were found out to be more effective than low-fat diets for weight loss, there’s also conflicting research findings describing the existence of metabolically benign obesity — obese individuals who are not insulin resistant, have normal levels of circulating insulin, and have zero signs of early atherosclerosis.

The main point is you don’t have to go low-carb, zero-carb, or high-carb to accomplish long term weight loss.

Instead, taking the following steps will help you maintain a healthy weight and body composition minus the guilt of consuming carbs:

• Focus on eating high-fiber, complex carbohydrates that will help you feel fuller for longer periods. In addition, pair carbs with protein and fat with each meal. Both macronutrients slow down digestion (avoiding sugar highs and crashes)  and help negate some the adverse effects of chowing down on high-carb foods. As always, moderation is the key.

• Refined carbohydrates are purportedly worse than the dreaded saturated fat. Eat more whole sources of carbs rather than its refined counterparts that have less or zero nutritional value.

• Prioritize physical activity on your daily routine. Moving regularly helps improve insulin sensitivity. Specifically, strength training has been shown to reduce insulin resistance in Type 2 diabetes patients.

The Bottom Line

Restrictive diets may work temporarily not because of the macronutrient you’re limiting yourself from, but because of the caloric deficit they create. Put simply, it’s because you’re eating less.

Based on recent research findings and established facts, it makes more sense to be more mindful of the specific types and amount of carbohydrates (and the other macronutrients!) that make up a bulk of your daily diet.

It’s very hard to deny the role carbs play in keeping you full, energized, and feeling good overall.  To a large extent, humans were designed to consume carbohydrates as an energy source, and when that source is limited and/or cut off, your body will not appreciate it – and it will let you know.

Should you cut carbs out of your diet? If it’s part of a general overall caloric reduction to lose body fat – which does work – combined with increased exercise, then yes. But simply hacking out an entire macronutrient source – any source – is not only going to be incredibly demanding on you, but also ineffective and unsustainable over the long-term.

And that says nothing about how much harder it can be to work out without your body’s favorite and preferred fuel source. That’s a story for another day.

Carbs, protein, and fat – your body needs them all.

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Kyjean Tomboc is a nurse turned freelance healthcare copywriter and UX researcher.  After experimenting with going paleo and vegetarian, she realized that it all boils down to eating real food.