Function and importance of carbohydrates

Carbohydrates are highly questioned items these days. International dietary rules suggest that we get about half of our calories from carbohydrates.

On the other hand, some claim that carbohydrates cause overweight and type 2 diabetes, and that most people should avoid them.

There are good arguments on both sides, and it seems that the amount of carbohydrates matters and their classification.

This article takes a detailed look at carbohydrates, their definition, classification, and how to choose between good and evil.

What are carbohydrates? – Definition

By definition, carbohydrates are molecules made up of carbon, hydrogen, and oxygen atoms.

Carbohydrates are probably the most abundant and widespread organic substances in nature, and they are essential components of all living things.

Green plants form carbohydrates from carbon dioxide and water during the photosynthesis process. (1)

Carbohydrates serve as sources of energy and as essential structural components of organisms.

In nutrition, the word carbohydrates refers to one of the three macronutrients. The other two are protein and fat.

In addition, carbohydrates are part of the structure of nucleic acids, the molecules that contain genetic information.

Carbohydrate classification

Although several classification schemes have been thought of for carbohydrates, we will emphasize a classification according to nutrition and biochemistry. Carbohydrates can be classified into:

  1. Simple carbohydrates or sugars

Short-chain or straightforward carbohydrates are found naturally in many foods. Examples are glucose , fructose, galactose, and sucrose. All sugar, honey, and fruit sugar fall into this category.

// Recommended: Simple carbohydrates – What are they?

  1. Complex carbohydrates or starches

Complex carbohydrates or starches are long chains of glucose molecules. These types of carbohydrates are mainly found in vegetables and cereals. They eventually break down into glucose in the digestive system.

// Recommended: Complex Carbs – Are They Good?

  1. Vegetable fiber

Vegetable fiber is a type of carbohydrate that cannot be digested by humans. Fiber is found in most fruit and grain peels. Fiber does not provide energy directly, but it feeds the digestive system’s friendly bacteria.

// Recommended: Vegetable fiber – Food

  1. Sugar alcohols

Sugar alcohols are also classified as carbohydrates. They have a sweet taste but are generally not very high in calories. Some examples are maltitol, erythritol, and xylitol.

// Recommended: Sugar alcohols – What are they?

Function and importance of carbohydrates

The primary function of carbohydrates in the diet is to provide energy. Most carbohydrates are broken down or transformed into glucose and are of great importance to fulfilling the parts of our body.

Carbohydrates can also be converted into body fat and serve as energy storage.

The amount of carbohydrates you should eat per day depends on your gender and age. According to WHO, the approximate value for an adult with about 300-350 g per day. (3)

Humans can use carbohydrates to provide about four calories per gram, like protein. Fat contributes nine.

Also, it is essential to know that not all carbohydrates are the same. Using the classification, you must reduce the simple ones and choose the complex ones.

In other words, to stay healthy, you should consume approximately 300g of good quality carbohydrates. Choosing whole grains and pseudo-cereals and distributing them throughout the day is a basic rule to maintain your ideal weight.

Recommended: How to eat without added sugar?

Are there good and bad carbohydrates?

As a general rule, carbohydrates in their natural high-fiber form are healthy or good, while those that have been stripped of their fiber are not.

With this in mind, it is possible to classify most carbohydrates as “good” or “bad,” but keep in mind that these are just rules of thumb. Things are rarely black and white in nutrition. Good carbohydrates are:

  • Vegetables: all
  • Whole fruits: apples, bananas, strawberries, etc.
  • Legumes: lentils, beans, peas, etc.
  • Nuts: almonds, walnuts, hazelnuts, macadamia nuts, peanuts, etc.
  • Seeds: Chia seeds, pumpkin seeds.
  • Whole grains: Choose grains that are indeed whole, such as plain oats, quinoa, brown rice, etc.

The bad carbs are:

  • Sugary drinks: Coca-cola, Pepsi, juices with sugar.
  • White bread – These are refined carbohydrates low in essential nutrients and high on the glycemic index.
  • Cakes, Cookies, and Sweet Products: These tend to be very high in refined sugar.
  • Ice Cream: Most types of ice cream are very high in sugar, although there are exceptions.
  • French Fries – Potatoes can be considered healthy, but French fries and French fries are not.


Is it good to reduce carbohydrates to lose weight?

Several methods and diets suggest that cutting carbohydrates to lose weight is good. The best known are the low-carb diet and the ketogenic diet.

These diets effectively lose in the short term and are even faster than following traditional diets. (2)

However, if your nutritionist does not suggest it, or you carry out these methods without the supervision of a professional, you will likely get a rebound effect.

Also, to cut carbohydrates, you must eliminate most fruits and grains. This can lead to a lack of vitamins and minerals and dehydration, dizziness, and gastrointestinal problems.

In other words, cutting back on carbohydrates too much can cause side effects.

Read more:


Carbohydrates are molecules made up of carbon, oxygen, and hydrogen atoms. The most common are glucose, sucrose, starch, and vegetable fiber.

There are several criteria for classifying carbohydrates. Considering its structure and uses in nutrition, four categories can be determined: simple, complex, vegetable fiber, and sugar alcohols.

While the terms good and bad carbohydrates are not entirely correct, it can be said that the bad ones are the isolates of their natural fiber like the sugar found in sodas, juices, and sweets.

Whole grains and sugar from fruits fall into the excellent category.

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *