toast and avocado

Carbs For Energy vs. Fats for Energy: Which is better?

While you might consider your morning coffee fuel or that heaped scoop of pre-workout, those stimulants aren’t what’s fuelling you. Your diet is your fuel, and the point of difference is carbs and fats. But which one works best? We’ll get to that.

Understanding how carbohydrates and fats function within our bodies is essential to maintaining overall health and performance. Both nutrients serve as primary energy sources for our bodies and play crucial roles in fuelling various bodily functions. While carbohydrates provide a more readily available (and preferred) energy source, fats can serve as a longer-lasting source, providing sustained energy over a longer period.

Understanding the basics of energy production

So, how do we produce energy? As we said earlier, you’re giving caffeine too much credit.

Understanding the basics of energy production is essential to leading a healthy lifestyle. Our bodies rely on the conversion of food into energy to function optimally. Just as a car requires fuel to run, our bodies need fuel to produce energy. This fuel comes in the form of protein, carbohydrates and fats.

There is a lot of discussion or ‘debate’ on whether a high-fat, low-carb diet (known as the ketogenic diet) is better for energy or whether carbs are still the best source of energy for your body to function. Whether you're interested in any of these diets including paleo, low-carb, high-fat or ketogenic - this article is for you.

Food is fuel and the energy your body requires to function throughout the day. Whether you’re sitting at your desk typing a blog about carbs vs. fats for fuel or lacing up your boots to compete in a marathon, energy is sourced from the foods & drinks that you consume. As we mentioned earlier, carbs, fats and protein are the three primary energy sources within your body. Carbohydrates are the most important of the trio, but protein and fats can be used when carbohydrate stores become depleted (Smith, A. 2021).

You’ve probably heard the term ‘metabolism’ floated around in the fitness world, and you’ve likely associated it with weight loss. It’s more important than that, though. Metabolism is the chemical reaction in the body’s cells that changes the food you consume into energy (Smith, A. 2021).

Much of the energy that your body needs is for rest, which is known as Basal Metabolism. Basal Metabolism refers to the minimal amount of energy required by your body to perform. This represents tasks as simple as breathing, circulation and organ function. Your Basal Metabolic Rate, or BMR, refers to the rate at which energy is utilised for the above functions and will vary depending on age, gender, height and weight (Smith, A. 2021).

Now, back to why metabolism matters. The foods you consume are metabolised at a cellular level to produce Adenosine Triphosphate or ATP. The process is referred to as cellular respiration, which is where ATP is utilised by the cell for energy that supports many cellular processes like muscle contractions and cell division (Smith, A. 2021).

Carbs vs. fats for fuel

Are carbs better for energy levels? Are fats for energy better? Are carbs the enemy? Will eating fats make me fat? We're answering all this (and more) and how they both can be used for energy. We think the answers might surprise you.

Do Carbs Assist with Energy?

Carbohydrates are the body's primary and preferred source of energy. They are broken down into glucose and then used by the cells to produce ATP, which is the body's energy currency. Carbohydrates are essential for the proper functioning of all bodily processes, from the movement and contraction of muscles to the operation of the nervous system (Pearson, K. 2023).

However, not all carbohydrates undergo this process of chemical digestion and absorption in the body. Complex carbohydrates, like sweet potatoes, beans and whole grains, are processed into glucose more efficiently compared to simple carbohydrates like candy and sodas. Eating good quality carbohydrates is crucial for optimal physical performance, and a deficiency in these could lead to a decrease in energy levels and, ultimately, cause fatigue. As such, incorporating complex carbohydrates into your diet, like whole-grain bread, brown rice, and oatmeal, is a smart choice if you want to keep your energy levels high and your body performing at its best (Kandola, A. 2019).

Types of Carbohydrates

We touched on this above, but let’s provide a little more insight. There are two types of carbohydrates: simple and complex. Let’s take a look at the difference.

Simple Carbs:

Simple carbohydrates are the ones that you find in sugary foods and drinks. Basically, simple carbs represent everything your grandmother likes to feed you and everything your parents disapproved of when you were growing up.

It’s not all grey skies, though. Simple carbs are found in fruits and vegetables, as well as milk and dairy products containing lactose. These types of simple carbs are rich in micronutrients. The simple carbs found in processed foods and sugar snacks are the ones to be wary of. These usually contain higher calorie content without any additional nutrition. Candy, soft drinks, fruit juice and cereal are all examples of simple carbohydrates that may cause more harm than good when consumed in excess (Kandola, A. 2019).

Complex Carbs:

Complex carbs are slower digesting and are usually highly nutritious. Complex carbohydrates are a more effective source of energy, and while they are found in processed foods, they are also highly prominent in nutritious types of foods like whole grains. Complex carbohydrates include whole grains like brown rice, oats and barley, while refined grains include white flour, white bread and white rice. Refined grains offer lower nutritional value than whole-grain foods (Kandola, A. 2019).

Don’t fall into the trap of assuming every complex carb is nutritional gold - there are plenty of examples where certain simple carbs can be more nutritious than certain complex carbohydrates. 

How Carbohydrates Provide Energy

Beyond merely being the body’s primary source of energy, carbohydrates are also the fastest and most efficient way to fuel yourself with energy. Simple carbohydrates are the quickest form of energy because they are made up of small molecules, meaning they can be broken down and absorbed quickly by the body. Simple carbs make ideal snacks right before training or sports and include easy options like cereal, toast, and granola bars (Bhupathiraju, S et al. 2023).

On the other hand, complex carbohydrates provide a slower source of energy (still quicker than protein and fats) and are important to consume earlier ahead of training to provide long-lasting energy. This includes rolled oats, pasta, and fruits like blueberries and raspberries (Bhupathiraju, S et al. 2023).

Additionally, carbohydrates can provide stored energy to be used at a later time. When your body has enough glucose to meet its performance needs, excess glucose can be stored for later use. This is known as glycogen and is mostly stored in the muscles and the liver. Between meals, the glycogen in your liver can be released into the blood to support energy throughout the body, helping to maintain blood sugar levels between meals. The glycogen in your muscles, however, is used exclusively by the muscle cells (Pearson, K. 2023).

If you’re training often or at a high intensity, consuming a carbohydrate-rich diet is essential. Carbohydrates are a must-have for their ability to delay the onset of fatigue and enhance endurance. Studies have shown that in intermittent sports like basketball and football, consuming carbohydrates before and during competition can optimise your performance and endurance. You should look at getting most of the calories in your diet from carbohydrates (as opposed to fats) to provide you with an effective fuel supply. You should aim to consume anywhere between 3-12 grams of carbohydrates per kilogram across the day (USADA. 2023).

Do Fats Assist with Energy?

First things first, let’s understand the difference between dietary fat and stored fat because both forms of fat tend to get a bad rep.

Dietary fat, which is often associated with an unhealthy lifestyle, is actually an essential nutrient for health. Stored fat, also known as the adipose tissue, provides support and insulation to your internal organs while protecting nerves and moving set vitamins throughout your body. Stored fat is also the largest reserve of stored energy used for activity. In contrast, stored fat refers to the body fat that is stored in the body when you consume more calories than you use (Quinn, E. 2023).

So, let’s talk about how fats are utilised for energy. Fats play a crucial role in providing our bodies with energy. When our body needs energy, it breaks down the stored fats into fatty acids to release energy. The energy produced through this process is used to carry out various bodily functions, from walking to breathing. Fats are less oxidised than carbohydrates, meaning they have a higher energy content per gram compared to carbohydrates (Voet, D et al. 2018)

This means that the body can store more energy in the form of fats to ensure that we have enough energy to function over a longer period. A diet high in healthy fats can actually aid weight loss and provide energy for exercise. It's all about choosing the right kind of fats to consume, such as those found in nuts, seeds, olive oil, and avocados. So, if you're looking for a sustainable source of energy, consider incorporating healthy fats into your diet (Robinson, L et al. 2023).

Types of Fats

Let’s take a look at the different types of fats. The four main types are:

Monosaturated Fats: This is one of the healthy fats and is found in plant foods like nuts, avocados and olive oil (Medline Plus. 2022).

Polyunsaturated Fats: One of the healthy fats found in plant and animal foods like salmon, seed oils and certain nuts & seeds (Medline Plus. 2022).

Saturated Fats: A fat found in foods like palm oil, ice cream, ghee, butter, cheese and red meat. Consuming these in excess can lead to weight gain and other health issues such as high cholesterol (Medline Plus. 2022).

Trans Fats: These are considered the worst type of fat to eat. These fats can raise bad cholesterol and lower good cholesterol, leading to greater health risks. They are found in fried foods, some frozen meals, hydrogenated oils such as vegetable oils, commercial baked goods and more (Mayo Clinic. 2022).

How Fats Provide Energy

Fats have always had a bad reputation for being unhealthy, but they are crucial for providing energy to our bodies. Medium-chain triglycerides (MCTs) are unique fats that are used as energy for the brain. MCTs can help your body to produce ketones, which are an energy source for your brain that doesn’t have carbs. It can be used to sharpen your mind and can deliver a long-lasting brain boost - queue Switch Nutrition’s MCT Oil Powder (Wiginton, K. 2022).

Prioritising healthy fats actually has a positive effect on blood glucose control in comparison with dietary carbohydrates and saturated fats. Healthy fats can lower blood sugar levels and improve insulin control (Brazier, Y. 2016).

Unlike carbs, fats don't trigger an insulin response, which means our bodies are far less likely to store them when they are our primary fuel source. When your metabolism primarily uses fats as an energy source, your body learns to use fats more often and more efficiently. As a result, the metabolic pathways involved in ketogenesis become more robust, and your body becomes better at using fat stored in the adipose tissue when sufficient calories are not available from food (Galvan, A. 2012).

The ketogenic diet follows a more fat, less carbs approach that can increase your focus and energy. This diet changes the way your body uses food for energy, reducing the carbs you eat and teaching your body to use fats for fuel instead. While you typically use glucose for fuel, your body now uses ketones for fuel in this kind of diet. Fats come into play when glycogen reserves aren't adequate to supply the whole body with energy, and when exercising, the stored fat is broken down into fatty acids and transported to the blood to be used for energy (Cleveland Clinic. 2022).

For your body to obtain energy from those fats, triglycerides must be broken down into fatty acids and glycerol. This process is called lipolysis. Because one triglyceride molecule bears three fatty acid molecules, fat molecules bear more energy than carbs and are a good source of energy for the body (LibreTexts Biology).

How to eat for performance

How you fuel your body will ultimately depend on what you are doing during the day. We can’t all be at the gym every day, and we can’t all keep our bodies in exercise mode. Some of us, unfortunately, have sedentary jobs like manning an office desk for the best part of the day.

If you’re sitting at a desk all day, you’re not going to need to fuel yourself with as high an amount of carbs as you might use if you were, say, running a marathon. In fact, if you’re sitting in an office, a combination of carbs and fats are likely the most effective fuel source, as they provide a concentrated source of energy that is optimal for low to moderate levels of activity. When it comes to fats, they are also offer more than twice the potential energy that protein and carbs do, with fats delivering nine calories per gram of fat, while protein and carbohydrates offer four calories each (Human Kinetics).

When it comes to high-performance exercise, this is where the story changes. Your ability to perform at high levels, whether in marathons or other high-endurance sports, will depend on the nutrients that you are fuelling yourself with. If you’re a marathon or long-distance runner, you should aim to get most of your daily calories from carbohydrates. Complex carbohydrates are best for sustained energy, but simple carbs are most effective for immediate energy and should be taken right before a long run (Pronschinske, J. 2023).

When it comes to bodybuilding or regular gym training, carbohydrates are once again the go-to fuel source. Carbohydrates are ideal for medium to intense training and can impact hormones (insulin growth factor-1. Insulin, and testosterone). Carbs are also essential in muscle growth and are important if you’re trying to bulk in your diet (SDA).

Best Carbs to Eat for Energy


When it comes to performance, especially at a high-intensity level, it is essential to fuel yourself with simple carbohydrates right before performing and complex carbohydrates during the day for sustained energy. These best carbohydrates for performance include (USADA):

  • Bagels
  • Pasta
  • Fruits
  • Yoghurts
  • Cereal
  • Low-fat milk
  • Peanut butter
  • Sports drinks
  • Granola bars

If you are looking for a way to conveniently consume carbs, you can try adding in a pure carbs powder to your shakes, smoothies or yoghurt bowls. Check out our range here.

Best Fats to Eat for Energy

Nuts and avocado

Healthy fats are essential in ensuring you meet your individual energy needs each day while also supporting healthy hormone levels. Here are some of the best dietary fats that you can incorporate into your diet (UWHealth. 2019).

  • Nuts
  • Nut butters
  • Avocados
  • Olive oil
  • Coconut (MCT) oil

The bottom line

While there has been a long-standing debate over whether carbs or fats are better for energy, the truth is that both play important roles in fueling our bodies. Carbs are quickly broken down into glucose, providing an immediate source of energy, while fats are stored and used for longer periods of sustained energy.

Additionally, both carbs and fats are vital in maintaining the health and function of our bodies, so while we may be commonly advised to cut out one or the other, a healthy balance of both is key to maintaining overall health and wellness.

If you want to learn more about the difference between carbs and fats and how they can be used to fuel you throughout the day or need help finding the best supplements to support your nutrition goals, our team can help you out. Simply head in-store or reach out online for more advice.


Smith, A. 2021, ‘How Does The Body Produce Energy?’ Metabolics, accessed 28 July 2023,


Pearson, K. 2023, ‘What Are the Key Functions of Carbohydrates?’ Healthline, accessed 28 July 2023,


Kandola, A. 2019, ‘What to know about simple and complex carbs’, Healthline, accessed 28 July 2023,


Quinn, E. 2023, ‘Converting Fat to Energy: Understanding the Process’, Very Well Fit, accessed 28 July 2023,


Robinson, L et al. 2023, ‘Choosing Healthy Fats’,, accessed 28 July 2023,


Voet, D et al. 2018, ‘Lipids and Biological Membranes’, Voet’s Principles of Biochemistry, accessed 28 July 2023,,stored%20in%20their%20anhydrous%20state.


Bhupathiraju, S et al. 2023, ‘Carbohydrates, Proteins, and Fats’, MSD Manual, accessed 28 July 2023,,-proteins,-and-fats#:~:text=Simple%20carbohydrates%3A%20Various%20forms%20of,the%20quickest%20source%20of%20energy.


USADA. 2023, ‘Carbohydrates The Master Fuel’, USADA, accessed 28 July 2023,,muscles%20and%20liver%2C%20called%20glycogen.


Medline Plus. 2022, ‘Facts about monounsaturated fats’, Medline Plus, accessed 28 July 2023,,are%20solid%20at%20room%20temperature.


Medline Plus. 2022, ‘Facts about polyunsaturated fats’, Medline Plus, accessed 28 July 2023,,and%20some%20nuts%20and%20seeds.


Medline Plus. 2022, ‘Facts about saturated fats’, Medline Plus, accessed 28 July 2023,,high%20amounts%20of%20saturated%20fat.


Mayo Clinic. 2022, ‘Trans fat is double trouble for heart health’, Mayo Clinic, accessed 28 July 2023,,heart%20and%20blood%20vessel%20disease.


Wiginton, K. 2022, ‘MCT Oil’, WebMD, accessed 28 July 2023,,will%20make%20your%20mind%20sharper.


Brazier, Y. 2016, ‘Eat more healthy fat to reduce the risk of type 2 diabetes’, Medical News Today’, accessed 28 July 2023,


Galvan, A. 2023, ‘Teaching the body to use fat as primary energy at rest - changing body composition’, Research Gate, accessed 28 July 2023,'t%20directly,are%20your%20primary%20fuel%20source.


Cleveland Clinic. 2022, ‘Ketosis’, Cleveland Clinic, accessed 28 July 2023,,on%20ketones%20than%20on%20glucose.


LibreTexts Biology. ‘10.4: Lipid Metabolism’, LibreTexts Biology, accessed 28 July 2023,


Human Kinetics. ‘The Body’s Fuel Sources’, Human Kinetics, accessed 28 July 2023,


Pronschinske, J. 2023, ‘Fueling your run with good nutrition’, Mayo Clinic, accessed 28 July 2023,,that%20can%20be%20used%20immediately


SDA. ‘Bodybuilding’, Sports Dietitians Australia, accessed 28 July 2023,,are%20important%20for%20muscle%20growth.


USADA. ‘Carbohydrates: The Master Fuel’, USADA, accessed 28 July 2023,,%2C%20yogurt%2C%20and%20frozen%20yogurt.


UWHealth. 2019, ‘Eating for peak athletic performance’, UWHealth, accessed 28 July 2023,