If you are interested in nutrition, you may have come across the term carbohydrates, which are one of the three main macronutrients that provide energy for the body. But what does the prefix carbo mean, and why is it attached to the word hydrates? In this article, we will explore the meaning and origin of this prefix, as well as the types and functions of carbohydrates in our diet.
What Does Carbo Mean?
The prefix carbo comes from the Latin word carbo, which means charcoal or coal. This may seem strange, since carbohydrates are not black or solid like coal, but rather white or colorful and often found in plant foods. However, the reason for this name is that carbohydrates are composed of carbon, hydrogen, and oxygen atoms, and when they are burned (or oxidized) in the body, they produce carbon dioxide and water, just like coal.
What Are Hydrates?
The word hydrates refers to compounds that contain water molecules in their structure. For example, copper sulfate pentahydrate is a blue crystalline substance that has five water molecules attached to each copper sulfate molecule. When this compound is heated, it loses its water and turns into anhydrous (without water) copper sulfate, which is white.
Carbohydrates are also hydrates, because they have a general formula of Cn(H2O)n, where n is a positive integer. This means that for every carbon atom in a carbohydrate molecule, there are two hydrogen atoms and one oxygen atom, forming a water molecule. For example, glucose, the most common carbohydrate in nature, has a formula of C6H12O6, which can be written as C6(H2O)6.
What Are the Types of Carbohydrates?
Carbohydrates can be classified into three main types, based on their size and complexity: monosaccharides, disaccharides, and polysaccharides.
- Monosaccharides are the simplest and smallest carbohydrates, consisting of only one sugar unit. They are also called simple sugars. Some examples of monosaccharides are glucose, fructose, and galactose. Monosaccharides are the building blocks of larger carbohydrates, and they are the main source of energy for the cells.
- Disaccharides are carbohydrates that consist of two monosaccharides linked together by a chemical bond. They are also called double sugars. Some examples of disaccharides are sucrose (glucose + fructose), lactose (glucose + galactose), and maltose (glucose + glucose). Disaccharides are formed by a condensation reaction, in which a water molecule is released. They are broken down into monosaccharides by a hydrolysis reaction, in which a water molecule is added.
- Polysaccharides are carbohydrates that consist of many monosaccharides linked together by chemical bonds. They are also called complex carbohydrates or starches. Some examples of polysaccharides are glycogen, starch, and cellulose. Polysaccharides are formed by many condensation reactions, and they are broken down into monosaccharides by many hydrolysis reactions. Polysaccharides can have different structures and functions, depending on the type and arrangement of the monosaccharides.
What Are the Functions of Carbohydrates?
Carbohydrates have various functions in the body, depending on the type and amount of intake. Some of the main functions are:
- Energy production: Carbohydrates are the primary and preferred source of energy for the body, especially for the brain and the nervous system. The body can convert carbohydrates into glucose, which is then transported by the blood to the cells, where it is used to produce adenosine triphosphate (ATP), the universal energy currency of the cell. The body can store excess glucose as glycogen in the liver and muscles, and use it when needed. However, if the carbohydrate intake exceeds the storage capacity, the excess glucose can be converted into fat and stored in adipose tissue.
- Regulation of blood sugar: Carbohydrates can affect the level of glucose in the blood, which is regulated by the hormones insulin and glucagon. Insulin is secreted by the pancreas when the blood glucose level is high, and it stimulates the uptake of glucose by the cells and the storage of glycogen in the liver and muscles. Glucagon is secreted by the pancreas when the blood glucose level is low, and it stimulates the breakdown of glycogen in the liver and muscles and the release of glucose into the blood. A balanced intake of carbohydrates can help maintain a stable blood glucose level and prevent hypoglycemia (low blood sugar) or hyperglycemia (high blood sugar).
- Digestion and bowel health: Carbohydrates can also affect the digestion and bowel health, depending on the type and amount of intake. Some carbohydrates, such as fiber, are indigestible by the human enzymes, and they pass through the digestive tract unchanged. Fiber can have various benefits, such as increasing the bulk and softness of the stool, preventing constipation, lowering the cholesterol and blood pressure, and reducing the risk of colon cancer. However, too much fiber can cause bloating, gas, and diarrhea. Other carbohydrates, such as sugar alcohols, are partially digestible by the human enzymes, and they can have a laxative effect, causing abdominal discomfort and diarrhea.
How Much Carbohydrates Do We Need?
The amount of carbohydrates that we need depends on various factors, such as age, gender, activity level, health status, and personal preference. There is no one-size-fits-all recommendation for carbohydrate intake, but some general guidelines are:
- The Dietary Reference Intakes (DRIs) suggest that the acceptable macronutrient distribution range (AMDR) for carbohydrates is 45% to 65% of the total daily calorie intake for adults. This means that if you consume 2000 calories per day, you should aim for 900 to 1300 calories from carbohydrates, which is equivalent to 225 to 325 grams of carbohydrates per day.
- The World Health Organization (WHO) recommends that the total carbohydrate intake should be at least 55% of the total daily calorie intake, and that the intake of free sugars (added sugars and natural sugars in honey, syrups, and fruit juices) should be less than 10% of the total daily calorie intake. This means that if you consume 2000 calories per day, you should aim for at least 1100 calories from carbohydrates, which is equivalent to 275 grams of carbohydrates per day, and that you should limit your intake of free sugars to less than 200 calories, which is equivalent to 50 grams of free sugars per day.
- The American Diabetes Association (ADA) recommends that people with diabetes should consult with their health care provider to determine their individualized carbohydrate intake, based on their blood glucose level, medication, and lifestyle. Some people with diabetes may benefit from a lower carbohydrate intake, while others may need a higher carbohydrate intake. The ADA also suggests that people with diabetes should choose carbohydrates that are rich in fiber, vitamins, minerals, and phytochemicals, such as whole grains, fruits, vegetables, legumes, and low-fat dairy products.
Carbohydrates are one of the three main macronutrients that provide energy for the body. The prefix carbo means charcoal or coal, and the word hydrates refers to compounds that contain water molecules in their structure. Carbohydrates are composed of carbon, hydrogen, and oxygen atoms, and they have a general formula of Cn(H2O)n. Carbohydrates can be classified into three main types: monosaccharides, disaccharides, and polysaccharides. Carbohydrates have various functions in the body, such as energy production, regulation of blood sugar, digestion and bowel health, and more. The amount of carbohydrates that we need depends on various factors, such as age, gender, activity level, health status, and personal preference. A balanced intake of carbohydrates can help maintain a healthy and optimal body function.