Carbohydrates, also known as carbohydrates, are biomolecules composed mainly of carbon, hydrogen and oxygen. They are one of the main sources of energy for our body, forming part of foods such as cereals, tubers, fruits and vegetables. In this article we are going to delve into what exactly carbohydrates are, their types, their function in the body and how they influence our health.
What are carbohydrates?
Carbohydrates are essential macronutrients that the body needs for energy. Although their structure may seem simple, they perform vital functions for the body, such as providing energy to all cells, tissues and organs. Carbohydrates can be found naturally in a wide variety of foods, such as fruits, vegetables and dairy products, and are also added to processed foods in the form of sugars or starches.
Types of carbohydrates
Carbohydrates can be classified based on their chemical structure, which determines how they are absorbed and utilized by the body. There are three main types: monosaccharides, disaccharides, and polysaccharides.
Monosaccharides
These are the simplest carbohydrates, made up of a single molecule. Examples include glucose and fructose, both found in fruits and vegetables. Glucose is the main source of energy for cells, while fructose is known for its sweetness, found in fruits and honey.
Disaccharides
Disaccharides are made up of two monosaccharides joined together. A common example is sucrose, or table sugar, which consists of one glucose molecule and one fructose molecule. Other important disaccharides include lactose, found in dairy products, and maltose, found in certain grains and fermented products.
Polysaccharides
Polysaccharides are long chains of monosaccharides that perform more complex functions, such as energy storage. Starch, found in foods such as potatoes and rice, is an example of a polysaccharide used by plants to store energy. In humans, glycogen is the polysaccharide responsible for storing energy in the liver and muscles.
Functions of carbohydrates in the body
Carbohydrates have several essential functions in the body, the most important of which is to provide energy. Each gram of carbohydrates provides the body with 4 kcal, making them one of the fastest sources of energy available. Some key functions of carbohydrates include:
- Energy function: Glucose is the main fuel for the brain and muscles, being essential to maintain our daily activities, both physical and mental.
- Protein-sparing function: By efficiently providing energy, carbohydrates allow proteins to be used for more specialized functions, such as building tissue and synthesizing enzymes.
- Regulatory function: Carbohydrates such as dietary fiber help regulate intestinal transit and prevent digestive diseases.
- Cell building and protection function: They are part of important molecules such as DNA and ATP, essential for life.
In addition, carbohydrates also play a crucial role in the metabolism and synthesis of other organic molecules, such as fatty acids and proteins. Their adequate consumption is essential for the proper functioning of the nervous system and the maintenance of the body's energy balance.
How many carbohydrates should we consume daily?
The amount of carbohydrates we should consume varies depending on factors such as age, sex, level of physical activity and health status. Nutritional guidelines suggest that between 45% and 65% of daily calories come from carbohydrates. For a 2000-calorie diet, this translates to consuming between 225 and 325 grams of carbohydrates per day. It is important to remember that not all carbohydrates are created equal, so it is recommended to prioritize complex carbohydrates and limit the consumption of refined sugars.
Simple carbohydrates and complex carbohydrates
There are two main types of carbohydrates from a nutritional point of view: simple and complex.
Simple carbohydrates
Simple carbohydrates include monosaccharides and disaccharides, such as table sugar and the sugars found in fruits. These carbohydrates are digested and absorbed quickly, causing rapid spikes in blood glucose. Although these foods can provide immediate energy, excessive consumption can contribute to health problems such as type 2 diabetes and weight gain.
Complex carbohydrates
Complex carbohydrates, such as starch and fiber, are digested more slowly, providing a steady release of energy. Additionally, foods rich in complex carbohydrates, such as whole grains and legumes, are an excellent source of fiber, which promotes digestive health and helps control blood sugar levels.
Glycemic index and its importance
The glycemic index (GI) is a measure that ranks carbohydrate-rich foods based on their ability to raise blood glucose levels. High glycemic index foods, such as white bread and potatoes, cause rapid glucose spikes, while low glycemic index foods, such as whole grains, promote a more controlled release of glucose.
Eating a diet based on low GI foods can help control weight, improve energy and reduce the risk of chronic diseases such as type 2 diabetes and cardiovascular disease.
What foods contain carbohydrates?
Carbohydrates are present in a wide variety of foods, including:
- Grains and cereals: Bread, pasta, rice, oats and other cereals such as wheat, barley and corn.
- Starchy vegetables: Potatoes, sweet potatoes, corn and peas.
- Fruits: Apples, bananas, melons, oranges and berries.
- Dairy products: Milk, yogurt and cheeses.
- Vegetables: Beans, lentils, chickpeas and peas.
- Processed foods: Many cookies, cakes and soft drinks contain high amounts of added sugars.
Carbohydrates and weight loss
A common myth is that carbohydrates are the culprits of weight gain. However, what really determines whether you gain or lose weight is the balance between calories consumed and calories burned. Consuming too many carbohydrates, especially simple carbohydrates, can lead to weight gain, but a balanced diet that includes complex carbohydrates can help maintain a healthy weight. Additionally, complex carbohydrates, having a lower glycemic index, help keep you feeling full for longer.
In short, carbohydrates are essential for the proper functioning of the body. They provide the energy needed for our daily activities, regulate various metabolic functions and are essential for a balanced diet. It is important to choose good quality carbohydrates, such as those found in fruits, vegetables, whole grains and legumes, and to avoid excessive consumption of added sugars and refined carbohydrates.