Essential Macronutrient: Carbohydrates
Have you ever wondered what carbohydrates were and why they are always talked about? More often than not, you probably overheard a conversation about carbs and thought that the best thing to do is avoid them, right? But, it’s not just the people around you that talk about carbs; the media is another major outlet for discussing healthy diets.
Carbs are talked about so much regarding diets that, as humans, we have become so alert to find out what foods contain carbs. We also wonder whether or not carbs are healthy to eat or if carbs make us fat. More importantly, one popular question about carbs is how much should a person eat?
These are all valid questions because, after the COVID pandemic, we just don’t know what is up from down or left from right anymore. Our health is and will always be a topic to discuss because there is nothing more important. So let’s just acknowledge that it is perfectly fine to ask questions about what foods are healthy or unhealthy if it is going in our bodies.
With all that said, rule number 1 regarding nutrition: THERE IS NO SUCH THING AS GOOD OR BAD FOOD! Just to get that out of everyone's head, your relationship with food is dependent on this rule. Plenty of factors contribute to disordered eating behaviors, and categorizing food choices into these buckets can weaken your relationship with food (Keel et al., 2013).
1. What are carbohydrates?
Carbs are often referred to as simple or complex carbs. What does this mean? They are also different types of sugar. Carbs are categorized as simple or complex because of their chemical structure.
Simple carbs include one or two sugar molecules linked together. Monosaccharides and disaccharides are known as simple carbs. “Mono” equals one, and “di” equals two. Below is a table of the most common simple sugars:
6 common simple carbs in nutrition
Complex carbs refer to any chain of sugar units longer than 3. These complex carbs are called oligosaccharides (3-10 units) or polysaccharides (≥ 11 units). Polysaccharides are starches (amylopectin & amylose), glycogen, dietary fiber, and cellulose.
Starches are one of the most common carbs found in the world. Structurally, there are two types of starches. A straight chain of glucose is called amylose, and a branched-chain is called amylopectin. These starches come from plant-based foods.
Glycogen is a storage form of carbs in animals. Similar to amylopectin in structure, the difference is in the number of extra branches. Glycogen is an important storage form of energy and is usually found in the liver and muscles.
Cellulose is basically dietary fiber and comes from fruits, vegetables, legumes, and whole grains. It is similar to starches because of the structural arrangement. However, a specific bond makes it impossible for humans to digest.
2. Why are carbohydrates essential? What functions do they have?
Simply put, carbs are essential for the following reasons: energy metabolism, regulation of protein and fat metabolism, the single best energy source for the brain, and significant for making DNA and RNA.
Carbohydrates role in the body
So what does this mean? Whenever carbs are eaten, one of two things will happen. Either carbs are used immediately for energy or stored in the muscle and liver for later use. When carbs are used for energy, they are broken down into glucose. At this point, glucose needs to be metabolized into different structures to make ATP (energy).
More importantly, eating carbs will prevent the body from using protein as an alternative source for producing ATP. In addition, carbs will prevent dietary fat from breaking down into ketone bodies. In turn, carbs allow dietary fat to do its primary job and support cell membrane health.
Furthermore, carbs help make DNA and RNA. These nucleic acids require 5-ring sugars to form our genetic information. These are many reasons why carbs are essential to our diet.
3. Are carbohydrates healthy?
Short answer: Yes!
If you got this far, understand that carbs are necessary for supporting healthy lifestyles. What is not healthy is demonizing carbs and avoiding them because someone said they cause chronic diseases. If anybody told you that eating candy and sweet treats gives you diabetes, they oversimplified it. Many factors are associated with diabetes, and genetics plays a significant role. Correlation does not mean causation!
4. What foods have carbohydrates?
Fruits
Vegetables
Whole grains
Legumes
Sugar-sweetened beverages
Honey
Maple syrup
Agave
Alcohol
5. How many carbohydrates do I need to eat per day?
The acceptable macronutrient distribution range (AMDR) found that 98% of healthy Americans eat 45-65% of their total calories from carbs. According to the Institute of Medicine, the significance of carb intake is related to the associated micronutrients and not solely for energy needs.
Essentially, how many carbs a person should eat is relative to many factors like health conditions, physical activity level, age, etc. In terms of proportions, an adult with a sedentary lifestyle may need far less than a growing teen running around doing extra-curricular activities.
[DISCLAIMER: this is not a one-size-fits-all approach, but an example for simplicity]. Let’s use a 2,000-calorie diet as a hypothetical meal plan for both people. The amount of calories from carbs is 900 to 1,300, based on the AMDR. A sedentary adult is not required to consume the upper limit of the dietary reference intake (DRI). Because it is likely from a balanced diet, they are getting all the nutrients for supporting health. On the other hand, an active teen would not benefit from consuming the lower end of the DRI because they expend more energy.
So how does this answer the original question? As illustrated in the example above, the amount truly depends. Unless every person owns an indirect calorimeter, we are going to have to ballpark estimate what our needs are based on our lifestyle. In the grand scheme of things, metabolism is very dynamic, and it would be impossible to consistently meet our needs every day. So stop worrying about how much is too much, and make sure to eat a well-balanced diet with lots of variety.
6. Do carbohydrates make you fat?
This is a question that is often asked. The only reason this is a conversation topic is due to the media. Going back to the phrase energy in versus energy out, we can partially fill in the gaps for how this conversation persists.
An extremely sedentary person that regularly consumes energy-dense carb-containing foods beyond their energy needs can gain weight. What does that mean? Somebody that is not physically active and consistently eats excessive carbs will store the extra energy as fat. Even this is an oversimplification.
Takeaway: carbs do not directly contribute to weight or fat gain. Everything about nutrition is multifactorial. There are no absolutes in nutrition, meaning nothing directly causes anything.
