Why Do We Need Carbohydrates for Fitness and Health?

Why do we need carbohydrates? Recent trends have led us to believe that we don’t need them at all, with many diets building a foundation on cutting carbohydrate foods out completely. Here is what you need to know for health and performance.

I recently worked with a client that had been following a keto diet off and on for a few years. She mentioned that the diet worked for a while, but then she started to gain weight even without eating carbohydrates. While following keto she also skipped breakfast and ate lunch as her first meal. 

Following a fad diet like keto, she was tricking her body to burn fat for energy instead of carbohydrates which is not sustainable. So what did we do? I helped her gradually re-introduce carbohydrates, and added breakfast to her daily meals. This jump started her metabolism and sped up the weight loss process. She dropped 6 pounds in the first month and continued to lose weight steadily for the remaining 3 months for a total of 25 pounds in 4 months. Now she enjoys her new healthy body weight and eating a balanced diet that contains all the macronutrients for better health.

This scenario is unfortunately more common than you’d think - and it’s the power fad diets can have on people’s health. So, I’ve gathered some key things to know about carbohydrates, why they’re so important, and how many grams of carbs you should be eating each day.

What Are Carbohydrates?

Carbohydrates are probably the most important macronutrient for the everyday functions of your body. So, what are carbohydrate foods? Carbohydrates are mostly found in plant-based foods. In fact, many people are surprised to find out that fruits and vegetables are carbohydrates. Other sources of carbohydrates include:

• Bread

• Pasta

• Beans

• Sugar

• Dairy

• Crackers

• Chips

• Pastries

As you can see, carb foods range widely from very nutritious (veggies like leafy greens) to downright empty calories (donuts and chips). This is a big reason why when people begin cutting carbs from their diet, they may feel better and lose weight. However, this is usually because they were cutting out high-calorie and processed foods, not because carbohydrates themselves were preventing weight loss. 

Whole vs. Refined Grains

The USDA recommends that you make about half of the grains you eat whole grains. This means about half of the time, you should swap your white rice for brown rice, or white pasta for whole-wheat pasta. 

Whole grains are important because they contain fiber and other key nutrients that are good from the body. High-fiber carbs are also great for keeping you feeling full, which can actually aid with weight loss.  These valuable nutrients are removed in processing to make refined carbs like white bread and rice. 

What is the Main Purpose of Carbohydrates?

Carbohydrates provide glucose, which in a basic sense is energy for the body. It is also the brain’s preferred source of fuel. So, what happens if you don't get enough carbohydrates? How do people on low-carb diets survive? 

Carbs as a Fuel Source

Well, the body can make its own glucose if you don’t eat enough carbohydrates. However, this process is quite inefficient and can still cause some brain fog due to the lack of brain fuel and fatigue from lack of muscle fuel. 

Even if you aren’t a super active individual, you still need carbohydrates to:

• complete your activities of daily living without feeling tired all the time

• fuel your brain to work your job or learn effectively in school

• socialize with friends

Carbs as a Nutrient Source

Finally, high-fiber carbohydrates like whole grains, oats, fruits and vegetables can provide long lasting energy due to the fact that they break down slowly in the stomach. These soluble and insoluble fibers have also shown to be good for the heart. 

And perhaps just as importantly, carb foods provide a wide range of phytonutrients, vitamins, and minerals vital for optimal health. These include nutrients such as:

• Vitamin A

• Vitamin E

• Potassium

• Zinc

• Selenium

• Magnesium

• Carotenoids

• Lycopene

Why Are Carbohydrates Important For Athletes

This brings us to why carbohydrates are important for exercise and athletic performance. However, before we get into talking about athletes specifically, let’s quickly talk about general guidelines.

Carbohydrate Recommendations for the General Population

The Dietary Guidelines for Americans, a comprehensive guide of recommendations released from the USDA every 5 years based on science collected from the American population, recommends that carbohydrates make up 45% to 65% of total daily calories. The USDA generalizes that most people eat around 2,000 calories a day. So, based on this standard, you this would mean eating between 225 and 325 grams of carbs a day to meet the guideline. 

If this seems confusing, especially for people who don’t count their calories, it’s okay. There is an even simpler method. The USDA My Plate method recommends that your plate is 50% fruits and vegetables, 25% is grains, and the other 25% is protein. Once you factor in the fats in your food sources, theoretically, this is another method to help you meet the recommendations.

Carbohydrate Recommendations for Athletes

So, how many carbohydrates should athletes eat? The guidelines vary widely depending on an athlete’s sport, the intensity of their activity and their current weight. However, sports nutritionists generally recommend a range of 5 - 7 grams per kilogram of body weight a day. 

If you are an endurance athlete (i.e. long distance runner, swimmer, cyclist) your needs are higher at 7 - 10 grams per kilogram of body weight a day. Why do endurance athletes need so many more carbs? It’s because of glycogen. 

Glucose is what is known as “blood sugar” and circulates in our blood for immediate fuel. Whenever there is more glucose in the blood than the body needs at the moment, it is stored in the liver and muscles as glycogen. 

The Importance of Glycogen

Glycogen is supremely important to athletes because, the more glycogen they have stored up, the longer they can participate in their training before they run out of fuel and fatigue. 

Since endurance athletes are required to train for extended periods, having optimized glycogen stores can prolong the need for surplus carbs. This is why it’s important that they consume more carbs than strength and power athletes to keep their glycogen stores as full as possible. 

As you can see, eating enough carbs is pretty much non-negotiable for athletes since they need sustaining energy to perform and generate explosive power for athletic performance. Even casual fitness enthusiasts should be sure to consume enough carbs before exercise (to have enough fuel) and after exercise (to refuel for the rest of the day).

The Bottom Line on Why We Need Carbohydrates

You can see for yourself how important carbohydrates can be and why dietitians urge people to include them in their diet, no matter what the latest fads are telling you. There has also not been a study published to date that shows that elite athletes following a long-term, low carb diet have seen improvements in their performance. 

If you are choosing carbs from the right sources and are not in a calorie surplus, carbohydrates will not cause weight gain and can actually promote health – so don’t be afraid of them! So many carbohydrate foods have many wonderful nutrients that nourish and fuel your body, especially for those who are active. If you want some guidance on how to structure your diet to meet your fitness goals, view the ways I can help you reach those goals.