Found in a variety of foods including fruits, vegetables, grains as well as dairy, carbohydrates are one of the three macronutrients alongside fat and protein. They are an essential source of energy for humans, acting as fuel for the body, muscles and brain. However, the quality and type of carbohydrates can vary. As a result, there are mixed opinions surrounding carbohydrates in the nutrition world. So, let’s explore what carbohydrates are, the pros and cons and some pointers on how to incorporate them into a balanced diet.
What are carbohydrates? Three basic categories

When thinking about carbohydrates the most common thought is probably pasta, potatoes, rice or bread. However, it’s a little more scientific than that. Carbohydrates are made up of carbon, hydrogen, and oxygen and can be split into three different categories based on their structure.
Firstly monosaccharides – the simplest type of carbohydrates – consist of a single sugar molecule e.g. glucose.
Secondly, disaccharides are two monosaccharides linked together e.g. sucrose.
And finally, polysaccharides consist of many monosaccharides linked together, forming complex carbohydrates e.g. glycogen.
Main forms of carbohydrates: how do they differ?
Carbohydrates come in various forms such as sugar, starch, and fibre.
When consumed the human body breaks down carbohydrates, converting them into glucose (sugar). The glucose can either be used immediately as energy, or stored in the liver and muscles as glycogen (which can be broken down later when energy is needed).
Fibre isn’t broken down into smaller molecules and absorbed by the body. Instead, it passes relatively intact through the stomach and intestines, providing bulk and digestive health benefits.
Starches, one of the most common forms of carbohydrates, are complex molecules made up of long chains of glucose molecules. They can be found in grains, potatoes, and legumes and are broken down into glucose by our digestive enzymes, providing a steady supply of energy to our cells.
So now we’ve discussed that, let’s move on to the pros and cons of carbohydrates for our health.
Pros of carbohydrates

Carbs are a crucial macronutrient that provides the body with some much-needed benefits.

1Contribute to gut health
As a source of prebiotic fibres carbohydrates are important for gut health. The prebiotic fibres promote ‘good’ gut bacteria in the intestines. Furthermore, these bacteria produce nutrients such as short-chain fatty acids, which can improve digestive disorders, immune function and reduce gut inflammation.
2Fuel brain work
Carbohydrates are essential for cognitive function. This is because the brain relies on glucose for energy. Therefore when glucose levels are low, fatigue can set in, resulting in problems concentrating or other cognitive difficulties.
3Help to regulate digestion
As previously discussed dietary fibre is a type of carbohydrate. Furthermore, fibre is essential for supporting a healthy digestive system, while also helping to regulate blood sugar levels and cholesterol levels.
4Accompany essential minerals and vitamins
Healthy carbohydrates, such as wholegrains, pulses and lentils, are a good source of essential vitamins and minerals including thiamine, riboflavin, niacin, and folate. These are known as B vitamins and help the body with metabolism, creating new blood cells, and maintaining healthy skin cells, brain cells, and other body tissues.
5Make up sustainable part of food system
Carbohydrate-rich foods, including legumes and whole grains, are affordable, environmentally sustainable, and culturally significant. As a result, carbohydrates play a role in a more sustainable and ethical food system. For example, compared to beef burgers, vegetarian alternatives are associated with up to 98% less greenhouse gas emissions.
Cons of carbohydrates

While carbohydrates are an important source of energy and nutrients, there are some potential downsides to consuming too many of them, particularly in the form of refined and processed carbs. The last include foods that have had many of the natural ingredients and nutrients stripped away, such as: packaged cereals, white bread and rice, cakes and biscuits, sweets and pastries, pies, pasta, beer, etc.

Consuming too many high glycemic index (GI) foods – like rice, potatoes or white bread – results in spikes in blood sugar levels. Repeated consumption of high GI foods can eventually lead to insulin resistance and as a result of that type 2 diabetes.
Consuming sugary snacks, baked goods, and processed foods i.e. foods high in refined carbohydrates, leads to spikes in blood sugar and insulin levels. This causes cravings and hunger, which may lead to overeating and weight gain. Furthermore, carbohydrates are a rich source of energy, and excess energy is stored in the body as fat.
Refined carbohydrates e.g. white bread can lead to inflammation. Moreover, inflammation is linked to a variety of health problems, including heart disease, cancer, and arthritis.
Certain individuals can experience difficulties digesting certain types of carbohydrates, such as those found in beans and other legumes. As a result, digestive discomforts such as bloating, gas, and diarrhoea can occur.
Carbohydrate-rich diets can be unhelpful for people with certain medical conditions including insulin resistance, metabolic syndrome, or polycystic ovary syndrome (PCOS). This is because these conditions have the ability to impact the body’s ability to regulate blood sugar levels.
A high intake of simple carbohydrates found in sugar-sweetened beverages (SSBs) can lead to oral health problems. The sugars interact with the bacteria within the plaque and produce acid. Furthermore, this acid slowly dissolves enamel creating holes or cavities in the teeth, leading to tooth decay and tooth abscesses. In fact, SSB consumption is positively associated with tooth decay even when intake is less than one time per day.
Tips for including carbohydrates in your diet

Since carbohydrates make up a major part of diets throughout the world, here are some tips for getting the best out of them.

1Look out for nutrient-rich and complex carbohydrates
Choose carbohydrates that are rich in nutrients such as whole grains, fruit and vegetables. These foods are typically lower in calories and higher in fibre, vitamins, and minerals, which help to support and maintain several bodily functions.
2Find the right balance
Although carbohydrates are an important part of a healthy diet, it’s advised to balance them with other macronutrients, like protein and fat. Therefore, try to fill half a plate with fruits and starchy vegetables, a quarter with lean protein, and the other quarter with whole grains.
3Watch out for added sugars
Processed foods, such as SSBs, sweets, and baked goods, can be extremely high in added sugars. Frequent consumption of these foods can result in weight gain, tooth decay, and type 2 diabetes.
Fun & curious facts about carbohydrates
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The word ‘carbohydrate’ comes from the French word ‘hydrates de carbone,’ which translate to ‘hydrates of carbon.’
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Carbohydrates are not just found in food. They are also used in a variety of industrial applications, such as in the production of paper, textiles, and plastics.
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The world’s largest carbohydrate is the giant sequoia tree. These trees can grow up to 300 feet tall and contain billions of carbs in the form of cellulose (the compound that gives them their rigid structure).
Let’s sum up

When talking about carbohydrates it’s important to be aware of the potential effects of excessive consumption, especially simple carbohydrates such as those found in sugar-sweetened beverages. However, it’s also vital to highlight that all carbohydrates are not the same. Therefore, making informed choices about the types and amounts of carbohydrates we consume can result in a more balanced diet, a higher intake of nutrient-dense foods and various health benefits.
Hungry for knowledge? Here’s more
Check out this short and fascinating animation from TED-Ed YouTube channel, in which educator Richard J. Wood explains how the things we eat and drink on a daily basis can impact our health in big ways. More specifically, carbohydrates.