And they are not carbohydrates. Carbohydrates and their functions
Carbohydrates are often remembered with shudder, believing that they are the cause of excess weight and various diseases. If you don't abuse them, nothing like this will happen. On the contrary, the role of carbohydrates in the human body is to provide it with the necessary recharging. A person who does not get enough of them looks sick and tired.
What are carbohydrates for humans?
Carbohydrates are commonly called compounds formed by carbon, oxygen and hydrogen atoms. These include starch-containing and sugary substances. Each of them performs its own function. After all, their molecules contain different elements. It is also common to classify carbohydrates as:
- simple, which include monosaccharides and disaccharides;
- complex, containing polysaccharides.
The first group includes:
- glucose;
- fructose;
- galactose;
- lactose;
- sucrose;
- maltose.
Their sweet taste in products is impossible not to notice. They quickly dissolve in water. These substances can quickly provide energy to a person because they are easily absorbed.
The second group contains starch, fiber, glycogen and pectin.
Function in humans
Entering the human body mainly from plant foods, carbohydrates not only allow the release of energy from it. Their significance is enormous! There are other important functions that carbohydrates perform in the human body:
- Cleansing the gastrointestinal tract. Not all substances found in food are beneficial to the human body. Thanks to fiber and other carbohydrates, self-cleaning occurs. Otherwise, intoxication of the individual would occur.
- Glucose allows you to nourish the tissues of the brain and heart muscle, and participates in the formation of a key component for liver function - glycogen.
- Increase immunity and protect the body. Heparin prevents excessive blood clotting, and polysaccharides can fill the intestines with the necessary active substances to fight infections.
- Construction of the human body. Without carbohydrates, the appearance of certain types of cells in the body is impossible. Nucleic acid and cell membrane synthesis are prime examples.
- Regulation of metabolic processes. Carbohydrates can speed up or slow down oxidation.
- Helps in the breakdown and absorption of proteins and fats from food. Note that the compatibility of various types of carbohydrates with proteins and fats is taken into account to make it easier to break them down.
In order for carbohydrates to help and not harm the human body, it is necessary to consume them in limited quantities.
Diseases caused by excess carbohydrates
The main problem that a person can get from abusing carbohydrates is metabolic disorders. It triggers other undesirable consequences, in particular:
- reducing the rate of breakdown of nutrients;
- hormonal imbalance;
- increasing the level of fat deposition due to the transition of carbohydrates into fat molecules;
- development or progression of diabetes mellitus, as the cells of the pancreas that produce insulin are depleted.
An increase in blood glucose levels triggers a number of negative changes. In particular, it increases the likelihood of platelets sticking together, which leads to the formation of blood clots. The vessels themselves become fragile, which exacerbates heart problems and increases the risk of a stroke or heart attack.
In the oral cavity, glucose and fructose in combination with acids can create an environment for the development of pathogenic microflora. As a result, tooth enamel is destroyed, caries develops, and the color becomes unattractive.
How many carbohydrates should you eat?
In order to balance your own nutrition, it is recommended to adhere to the following carbohydrate intake norms:
- Children under one year of age should be given 13 g of carbohydrates per 1 kg of weight;
- for an adult under 30 years old who does not experience strong physical exertion, you need 300-350 g per day of these substances;
- after 30 years, the norm decreases by 50 g;
- for women, all norms should be 30–50 g less;
- for people involved in sports and leading an active lifestyle, it is allowed to exceed the norm by 40–50 g per day.
There must be at least 20 g of dietary fiber for intestinal self-cleansing to work well.
It should be remembered that there is a possibility of an allergic reaction to. Therefore, before including them in the baby’s diet, it is necessary to exclude the possibility of individual intolerance. It is better to do this in the morning.
Carbohydrate-rich foods should not be consumed in the evening, when metabolic processes in the body slow down. In addition, the energy that they will release will remain unclaimed. This does not apply to people working at night or on shifts. For them, you need to create an individual diet.
It is useful to know that for some sweet products, not only the volume of sugars in 100 g of the product matters, but also the amount of moisture. Water is easily removed from the body, leaving monosaccharides at work. If there is a lot of it in the product, then it may turn out that a person receives more glucose and other sugars than necessary.
One apple eaten throughout the day, which is supposedly able to provide the right amount of fiber, will not help the body. You need up to 5 unsweetened fruits to reach your normal daily intake.
You should not choose only starchy carbohydrates or monosaccharides. In order to provide the body with everything necessary, the balance between them should be approximately 1:1.5 in favor of the first (cereals, bread, etc.).
If you do not drink foods containing many of these elements with water or liquid, then the risk of their transformation into fats in case of exceeding the consumption rate is reduced. Therefore, it is better to drink one hour after eating.
Freshly squeezed juices should be consumed in a diluted form, so as not to put a strain on the internal systems and at the same time reduce the calorie content of the product.
The conclusion is simple: if you approach the consumption of carbohydrates wisely, their consumption will only bring benefits to the body!
For our body, carbohydrates are one of the key sources of energy. Today we will look at the types and also find out what foods they are contained in.
Why do people need carbohydrates?
Before looking at the types of carbohydrates, let's understand their functions. The human body always has a carbohydrate reserve in the form of glycogen. It is about 0.5 kg. 2/3 of this substance is found in muscle tissue, and another third in the liver. In between meals, glycogen breaks down into glucose, thereby leveling out fluctuations in blood sugar.
Without carbohydrates entering the body, glycogen stores run out in 12-18 hours. If this happens, carbohydrates begin to be formed from intermediate products of protein metabolism. These substances are vital for humans, since they mainly form energy in our tissues.
Shortage
With chronic carbohydrate deficiency, the glycogen supply in the liver is depleted, and fats begin to be deposited in its cells. This leads to liver degeneration and disruption of its functions. When a person consumes an insufficient amount of carbohydrates in food, his organs and tissues begin to use not only protein, but also fat for energy synthesis. Increased breakdown of fats leads to disruption of metabolic processes. The reason for this is the accelerated formation of ketones (the most famous of them is acetone) and their accumulation in the body. When ketones are formed in excess, the internal environment of the body “acidifies”, and the brain tissue gradually begins to be poisoned.
Excess
Like deficiency, excess carbohydrates do not bode well for the body. If a person eats too many carbohydrates, insulin and glucose levels in the blood rise. As a result, fat deposits are formed. This happens as follows. When a person does not eat all day after breakfast, and in the evening, coming home from work, decides to take lunch, afternoon snack and dinner at the same time, the body tries to fight excess carbohydrates. This is how blood sugar levels rise. In order for glucose to move from the blood into tissue cells, insulin is needed. It, in turn, entering the bloodstream, stimulates the synthesis of fats.
In addition to insulin, other hormones regulate carbohydrate metabolism. Glucocorticoids are hormones of the adrenal cortex that stimulate the synthesis of glucose from amino acids in the liver. The same process is enhanced. The functions of glucocorticoids and glucagon are opposite to insulin.
Norm
According to the norms, carbohydrates should be 50-60% of the calorie content of food. You cannot exclude them from your diet, despite the fact that they are partly “to blame” for the formation of extra pounds.
Carbohydrates: types, properties
According to their chemical structure, carbohydrates are divided into simple and complex. The former include mono- and disaccharides, and the latter are polysaccharides. Let's analyze both classes of substances in more detail.
Simple carbohydrates
Glucose. We begin to consider simple types of carbohydrates with the most important of them. Glucose acts as a structural unit of the main amount of poly- and disaccharides. During metabolism, it breaks down into monosaccharide molecules. They, in turn, in the course of a complex reaction are converted into substances that are oxidized to water and carbon dioxide, which are fuel for cells.
Glucose is an important component in carbohydrate metabolism. When its level in the blood drops or high concentrations make normal functioning of the body impossible (as is the case with diabetes), the person experiences drowsiness and may lose consciousness (hypoglycemic coma).
Pure (as a monosaccharide) is found in a large number of vegetables and fruits. The following fruits are especially rich in this substance:
- grapes - 7.8%;
- cherries and sweet cherries - 5.5%;
- raspberries - 3.9%;
- strawberries - 2.7%;
- watermelon and plum - 2.5%.
Vegetables rich in glucose include pumpkin, white cabbage and carrots. They contain about 2.5% of this component.
Fructose. It is one of the most common fruit carbohydrates. It, unlike glucose, can penetrate from the blood into tissues without the participation of insulin. Therefore, fructose is considered optimal for people with diabetes. Some of it goes to the liver, where it is converted into glucose - a more versatile “fuel”. This substance can also raise blood sugar levels, but not as much as other simple carbohydrates. Fructose is converted to fat more easily than glucose. But its main advantage is that it is 2.5 and 1.7 times sweeter than glucose and sucrose, respectively. Therefore, this carbohydrate is used instead of sugar in order to reduce the calorie content of food.
Most fructose is found in fruits, namely:
- grapes - 7.7%;
- apples - 5.5%;
- pears - 5.2%;
- cherries and cherries - 4.5%;
- watermelons - 4.3%;
- blackcurrant - 4.2%;
- raspberries - 3.9%;
- strawberries - 2.4%;
- melon - 2.0%.
Vegetables contain less fructose. Most of all it can be found in white cabbage. In addition, fructose is present in honey - about 3.7%. It is reliably known that it does not cause caries.
Galactose. Considering the types of carbohydrates, we have already become acquainted with some simple substances that can be found in free form in foods. Galactose is not like that. It forms a disaccharide with glucose called lactose (aka milk sugar) - the main carbohydrate of milk and products derived from it.
In the gastrointestinal tract, lactose is broken down into glucose and galactose by the enzyme lactase. Some people experience milk intolerance due to a lack of lactase in the body. In its undigested form, lactose is a good nutrient for intestinal microflora. In fermented milk products, the lion's share of this substance is fermented to lactic acid. Thanks to this, people who have lactase deficiency can consume fermented milk products without unpleasant consequences. In addition, they contain lactic acid bacteria, which suppress the activity of intestinal microflora and neutralize the effects of lactose.
Galactose, which is formed during the breakdown of lactose, is converted into glucose in the liver. If a person lacks the enzyme that is responsible for this process, he may develop a disease such as galactosemia. Cow's milk contains 4.7% lactose, cottage cheese - 1.8-2.8%, sour cream - 2.6-3.1%, kefir - 3.8-5.1%, yogurt - about 3%.
Sucrose. With this substance we will finish looking at simple types of carbohydrates. Sucrose is a disaccharide that consists of glucose and fructose. Sugar contains 99.5% sucrose. Sugar is rapidly broken down by the gastrointestinal tract. Glucose and fructose are absorbed into the human blood and serve not only as a source of energy, but also as the most important precursor of glycogen in fat. Since sugar is a pure carbohydrate containing no nutrients, many people call it a source of “empty calories.”
Beetroot is the richest product in sucrose (8.6%). Among other plant fruits, one can distinguish peach - 6%, melon - 5.9%, plum - 4.8%, tangerine - 4.5%, carrots - 3.5%. In other vegetables and fruits, the sucrose content ranges from 0.4-0.7%.
A few words should also be said about maltose. This carbohydrate consists of two glucose molecules. found in honey, molasses, confectionery, malt and beer.
Complex carbohydrates
Now let's discuss the types of complex carbohydrates. These are all polysaccharides that are found in the human diet. With rare exceptions, glucose polymers can be found among them.
Starch. It is the main carbohydrate digested by humans. It accounts for 80% of carbohydrates consumed in food. Starch is found in potatoes and cereal products, namely: cereals, flour, bread. Most of this substance can be found in rice - 70% and buckwheat - 60%. Among cereals, the lowest starch content is observed in oatmeal - 49%. Pasta contains up to 68% of this carbohydrate. Wheat bread contains 30-50% starch, and rye bread contains 33-49%. This carbohydrate is also found in legumes - 40-44%. Potatoes contain up to 18% starch, so nutritionists sometimes classify them not as vegetables, but as starchy foods, like grains and legumes.
Inulin. This polysaccharide is a polymer of fructose, which is found in Jerusalem artichoke and, to a lesser extent, in other plants. Products containing inulin are prescribed for diabetes and its prevention.
Glycogen. It is often called "animal starch". It consists of branched glucose molecules and is found in animal products, namely: liver - up to 10% and meat - up to 1%.
Conclusion
Today we looked at the main types of carbohydrates and found out what functions they perform. Now our approach to nutrition will be more meaningful. Brief summary of the above:
- Carbohydrates are an important source of energy for humans.
- Too much of them is just as bad as too little.
- Simple ones include mono- and disaccharides, and complex ones include polysaccharides.
It's no secret that any, even the most gastronomically sophisticated and exotic food, can be broken down into its component elements, the general name of which is macronutrients. The list of them is very short and well known:
- proteins;
- fats;
- carbohydrates.
In addition, each product contains water, vitamins and microelements in different proportions. It is in this disassembled form that food is absorbed by the body. Each meal, depending on the percentage of macronutrients, has a different effect on a person’s well-being. The thing is that each “brick” has its own function and serves different purposes. This article will take a closer look at carbohydrates and their functions.
Energy-dense foods are often associated with calories. Recently, it has become fashionable to exclude carbohydrate-containing foods from the diet, as it is believed that this reduces calorie intake. There is, of course, some truth in this approach. Especially if you are a professional athlete. However, first things first.
Science knows two types of them: monosaccharides and disaccharides. Among the monosaccharides, the most common and found in free form in nature are glucose and fructose. They are found in freshly squeezed juices and fruits. The chain of monosaccharides, as the name suggests, is the simplest, which facilitates their rapid absorption by the body. The formula of disaccharides (sucrose, maltose, lactose) is a chain of residues of several monosaccharides. Disaccharides are found in dairy products (lactose), (sucrose) and some cereals (maltose).
Another name for them is polysaccharides; they consist of several thousand monosaccharide residues, that is, they have a long and branched chain of simpler carbohydrates. The most famous representatives of this group are pectin, cellulose, starch and glycogen. Carbohydrates of this group are not absorbed by the body in their original form. Breaking them down into simple and easily digestible forms requires significant energy expenditure. Some types (fiber) are not digested at all. This helps to use them as a stimulant for the activity of the gastrointestinal tract and its cleansing of toxins. In addition, glycogen, for example, is a building material for the body (liver, muscles).
After we have found out what carbohydrates are, it makes sense to return to the question of their benefits for the body. It is obvious that their complex forms are useful and even necessary for the proper functioning of the body due to the fact that they perform a construction and nutritional function.
Due to the fact that polysaccharides are broken down with greater energy consumption and are absorbed more slowly, they are practically not deposited as fat, because they simply don't make it. Monosaccharides, on the contrary, are absorbed much faster and enter directly into the blood, causing a so-called “carbohydrate jump,” that is, they sharply increase energy. And their excessive consumption, in the absence of high energy consumption, leads to the processing of carbohydrates and their accumulation in the form of fat.
You need to know what carbohydrates are to build a healthy diet. The use of complex and simple forms is mandatory for the body, otherwise processes (including mental ones) slow down, lethargy and apathy occur.
