What Are Carbohydrates For And Why They Should Not Be Excluded From The Diet

The world is constantly changing – and with it new trends in nutrition are emerging. Now at the peak of popularity are low-carb diets - the number of their adherents is growing exponentially. Bloggers confidently assure their benefits to a wide audience - such a magic wand of health in the hands of every person. But are there pitfalls and, in fact, do we really not need this kind of organic compounds?

What are carbohydrates

Their absence, just like a sharp and significant decrease, negatively affects the entire body, inevitably disturbing inner peace and balance - the preservation of homeostasis is again under threat. So why have low-carbohydrate diets earned such popularity and what are they? Let's figure it out!

Types of carbohydrates

The classification of carbohydrates into “good” and “bad” is not so much primitive from a scientific point of view as it is not justified: everything is poison, and everything is medicine. The famous phrase of the Swiss alchemist Paracelsus best reflects all the subjectivity of such a division.

It would be much more correct to distinguish, based on the structure of these organic compounds, the following two groups: simple (“fast”) and complex (“long”). And the difference between them is as great as between finding the integral and a simple linear equation. However, let's switch our eyes from mathematics back to biochemistry.

This implies the following pattern: in order for the intestinal epithelial cells to absorb "long" carbohydrates, their bulky molecules must be split into constituent units - that is, to simple sugars. In other words, the silk thread of the decoration is cut by specific enzymes, and each bead individually (due to energy-dependent transport) will be delivered inside the enterocyte.

Thus, the cleavage process itself will be different: for example, if glucose (a typical representative of simple sugars) comes with food, it makes no sense for digestive juices to break it down - there is simply no “one” smaller. That is, the cells only need to absorb it. When, for example, starch enters our body with food, the work is much more cumbersome - and therefore lasts longer.

The role of saliva with amylase and maltase, which are contained along with other components in this biological secret, is not so great - especially considering how little we pay attention to the quality of chewing food. However, already getting into the small intestine and being exposed there to the action of various enzymes (as a rule, the pancreas plays the main role), large chains with side branches will be slowly but surely “cut”. Hence the name - "long".

The difference in digestion and absorption between these two types of carbohydrates will also affect insulin production. It is a hormone of protein nature, the main task of which is to ensure glucose homeostasis. That is, its values, being strictly regulated by the legislative code, must be invariably maintained within the specified limits. More - diabetes, less - hypoglycemia.

Insulin seeks to return the concentration of this monosaccharide that has increased after eating (postprandial) - it does this by increasing the density of carriers on the cell surface. The fact is that glucose, already being a monosaccharide (that is, a single brick), still cannot independently pass through the bilipid ball of the membrane - for this it needs a transporter.

It is noteworthy that both types of carbohydrates will affect insulin secretion: we have already said that in the process of abdominal and parietal digestion, complex structures of polysaccharides will be split into monomers, one of which is glucose. That's just the difference will be in the very schedule of the release of this hormone: when simple sugars enter the body, an instant increase in their concentration in the blood occurs, accompanied by an avalanche-like secretion of insulin. At the same time, the decline will be far from uniform. Imagine a hill with a steep ascent and an almost perpendicular descent-cliff - approximately the same is observed in the human body.

Monosaccharides include:

• Galactose or milk sugar - is an integral part of lactose. In the human body, through a series of successive transformations, it is metabolized to glucose. Contained in milk.

• Glucose or grape sugar - found in fruits, confectionery, honey. It is the end product of the breakdown of complex carbohydrates in the body, it is easily fermented. It is a favorite delicacy of bacteria and other pathogenic microflora.

• Fructose or fruit sugar is one of the most common monosaccharides that is actively used in industrial production - and this is not surprising, given that it is 2.5 times sweeter than sucrose and 3 times sweeter than glucose. It does not cause insulin secretion—and therein lies another insidiousness of fructose: this simple sugar bypasses all the ways and mechanisms of satiety.

Oligosaccharides are represented by:

• Sucrose (cane, beet sugar), the molecule of which consists of glucose and fructose. It is found in honey, dates, grapes, figs, persimmons, prunes, raisins.

Its excessive consumption is associated with the development of type 2 diabetes mellitus, obesity, and cardiovascular pathologies.

• Lactose, or milk sugar, is made up of one molecule of lactose and one molecule of galactose. The frequency of its intolerance has increased significantly in the population - and this, as it is not surprising, even with the fact that such a diagnosis was officially recognized only 50 years ago. Pathology is associated with a decrease in lactase activity and is manifested by the following set of symptoms:

1. Bloating.

2. Diarrhea.

3. Flatulence.

It is noteworthy that normally this process is genetically programmed: after all, an adult does not need to consume breast milk - this is why the function of this enzyme decreases.

• Maltose or malt sugar is an intermediate product of starch hydrolysis. Found in wheat, rye, malt extracts, sprouted grains.

So, complex carbohydrates include:

• Starch is stored in the form of grains in plant cells: in their seeds, fruits, and also tubers. It is formed in the process of photosynthesis and is a huge, long chain in which glucose is the building block. The digestion of this polysaccharide begins already in the oral cavity - under the influence of specific salivary enzymes. Contained in cereals (in particular, in wheat and rice), also in potatoes, pumpkins and peas.

   

• Glycogen is another polysaccharide consisting of repeating glucose molecules and also performing a reserve function - but already in the animal body. In humans, its depot is concentrated in the liver - approximately 200-220 grams of this complex carbohydrate occupies the space of its pantry, prudently created in case of a "rainy" day.

Glycogen is also concentrated in skeletal muscles - but those, being a greedy and hard-working tissue, use it for purely their own purposes: to obtain energy that provides contraction mechanisms.

• Cellulose is the main component of the cell wall of higher plants and algae. It does not undergo splitting in the digestive tract: a person does not have the enzymes necessary for this. Unlike homo sapiens, cows (being a representative of ruminants) do not feel this problem so acutely - or rather, they do not feel it at all: all thanks to the specific bacteria that inhabit its intestines and contribute to the digestion and assimilation of this carbohydrate.

I would like to dwell separately on fiber and its beneficial properties:

Dietary fibers undergo bacterial fermentation in the gastrointestinal tract. Some of them can act as prebiotics and, by causing certain changes, both in the composition of the microflora and in its activity, benefit the human body.

Interestingly, pronounced shifts in bacterial diversity are noted as little as 24 hours after eating a fiber-rich meal.

In addition, studies note that low dietary fiber intake is associated with a significant increase in the risk of cardiovascular disease, type 2 diabetes, and even colon cancer.

The use of fiber is also recommended for patients suffering from irritable bowel syndrome, one of the most common diseases in gastroenterology. Psyllium, for example, being a representative of long-chain, moderately fermented and soluble dietary fibers, practically does not lead to gas formation and its characteristic symptoms, stimulates peristalsis, and thereby contributes to the normalization of daily stools.

Dietary fiber increases the binding of bile acids and carcinogens, thereby providing a detoxifying effect in some way. In addition, they inhibit the absorption of estrogen in the intestines - it increases the amount excreted in the feces. And most hormone-dependent tumors are associated precisely with an increased concentration of this hormone. In particular, considering that in the conditions of the modern world, in the environment and the constant intake of various xenobiotics into the body, the mechanisms for neutralizing toxins, neurotransmitters, drugs and hormones are very limited.

Why do we need carbohydrates in the human body?

The functions of carbohydrates are different and very extensive. Let's look at some of them:

1. Energy is the main raw material in the energy production factory. The mechanism of burning glucose in cell furnaces has been perfected for centuries to perfection.

2. Structural - are components of the membrane, are involved in the production of lipids and essential amino acids, glycosaminoglycans, hyaluronic acid.

3. The formation of glucuronic acid is one of the key figures in the second phase of detoxification in the liver, which binds toxic indirect bilirubin.

4. Reserve - small reserves of glycogen are stored in the liver: in case of adverse effects such as starvation (so as not to use amino acids by turning on the processes of muscle protein catabolism).

5. They are part of cell receptors, thus performing a signaling function.

6. Regulate one of the most important parameters of homeostasis: osmotic pressure. Its slightest fluctuation away from the norm leads to a malfunction of the enzymatic systems and entails a number of adverse and life-threatening consequences.

7. They participate in the formation of nucleic acids (DNA and RNA), and are also part of the universal energy source - ATP.

Lack and excess of carbohydrates in the body

With excessive and frequent intake of carbohydrates in the body, relentless secretion of insulin occurs: the concentration of glucose in the blood rises, and it seeks to return everything to its original balance. Such a constant circulation of a protein hormone leads to a loss of sensitivity to it by cellular receptors: it simply bothers them already with its memorized mechanisms of action. Insulin resistance develops.

So, glucose is forced to remain in the blood: without the help that insulin cannot realize in such a situation, it cannot enter the cell. And here the most interesting thing happens: any fasting is equated at the cellular level with death. No energy, no life. Despite all their stubbornness, cells do not want to die, and therefore they find a way out: since they decided not to let glucose through the customs border in the form of a plasma membrane, they synthesize it themselves, inside themselves! The gluconeogenesis factory is activated.

The main symptoms of insulin resistance are:

1. Waist circumference over 80 cm for women and over 90 cm for men.

   This is one of the simplest, but at the same time informative indicators that reflect the presence or absence of NAFLD - non-alcoholic fatty liver disease.

2. Blackening of the skin in the places of the elbows, in the armpits, groin and neck folds - the so-called acanthosis nigricans.

3. Anovulation, excessive male pattern hair growth, alopecia, acne, oily skin and other manifestations of polycystic ovary syndrome, observed with an increase in androgen levels. The fact is that insulin stimulates liver cytochromes responsible for the formation of key enzymes in the synthesis of these hormones.

4. Increased blood pressure: insulin retains sodium, which pulls water with its tail - an increase in the volume of circulating blood occurs.

5. The appearance of vascular angiomas (red dots) and papillomas.

6. Reduced fluidity of bile - due to increased formation of cholesterol.

Norms of consumption of carbohydrates

The norms of carbohydrate consumption are quite individual and largely depend on gender, age and physical activity. Below are the average values:

Carbohydrates

Gram per day

Complex carbohydrates

210

Cellulose

40

Fructose

25

sucrose

25, max 50

Total

300

The essence of carbohydrate metabolism

With an increase in the concentration of glucose in the blood (which occurs naturally after eating), the pancreas begins to actively secrete insulin. The task of the latter is not only to send glucose into the cell, but also to involve the processes of its utilization. Otherwise, she is a capricious lady: if she wants to, she will be able to go back (it is inconvenient for cells to store this carbohydrate: you have to connect further mechanisms to turn it into a more “diligent” form).

There are several such options:

1. Glycolysis is one of the key points in the way of obtaining energy. Occurs, unlike other processes of catabolism, in the cytoplasm. In the absence of oxygen (that is, under anaerobic conditions), it ends with the formation of lactic acid - lactate. This, in fact, is observed in the muscles during their active work. However, given that any shift in pH threatens the body with serious consequences, the accumulation of acidic foods, of course, is not the most reasonable idea, which is a direct path to the development of acidosis. Therefore, lactate from the muscles goes to the liver - and there, passing through the pyruvate stage, it turns back into glucose, which, when it enters the bloodstream, returns back to the skeletal muscles - this is the so-called measles cycle.

   In the presence of oxygen, the pyruvate (pyruvic acid) formed in glycolysis, through the action of a whole complex of enzymes, is transformed into a universal token in the Krebs cycle slot machine - acetyl-CoA.

2. Glycogen synthesis - when an excess of glucose enters, a part will be stored in the liver. However, the square footage of her pantry is very limited - and anything that doesn't fit in will go to the formation of fats.

   It is noteworthy that with an increased concentration of glucose in the blood observed in diabetes mellitus, one of the mechanisms of kidney damage is precisely the synthesis of glycogen: it infiltrates into the epithelial tubules of this parenchymal organ.

3. Pentose phosphate pathway - provides the body with pentoses necessary for the formation of DNA and RNA, as well as NADPH2, which is one of the coenzymatic forms of vitamin B3 (nicotinic acid) and is involved in the synthesis of cholesterol (and, consequently, hormones of the adrenal glands and gonads, as well as vitamin D) and resistance of erythrocytes to hemolysis.

The root causes of carbohydrate metabolism disorders:

• Excess intake of glucose and other simple carbohydrates - there is a constant stimulation of the synthesis and secretion of insulin.

• Sedentary lifestyle, low physical activity.

• Fractional meals and snacks.

• Exposure to stress factors: cortisol stimulates the previously mentioned process of gluconeogenesis (under its influence, three enzymes are formed that catalyze irreversible reactions).

• Violation of sleep hygiene: as you know, melatonin is the main antagonist of cortisol, which, moreover, has a pronounced antioxidant ability. A decrease in its secretion is negatively reflected in the overall resistance of the body to irritating factors and invariably leads to obesity.

In addition, somatotropin (a growth hormone known for its fat-burning effect), as well as leptin and ghrelin, are associated with the sleep-wake cycle, which are responsible for satiety and hunger, respectively.

Principle of a low-carbohydrate diet

All the "magic" of low-carbohydrate nutrition can be expressed in the following theses:

• significantly suppresses the feeling of hunger - due to the high fat content (for comparison: 1 gram of carbohydrates provides us with 4 kilocalories, and 1 g of fat - more than 9!);

• intermittent fasting comes naturally;

• it is easy to stick to 2 or 3 meals a day and exclude all snacks;

• receptors "wean" from sugar addiction, sweet ceases to affect the reward system;

• we fix the result (no hunger - no kickbacks, breakdowns and subsequent weight gain).

LCHF also has positive effects on the regulation of impaired carbohydrate metabolism: in particular, there is a significant decrease in the level of glycated hemoglobin (an important indicator that reflects the average glucose concentration over several months). In addition, adherent patients had significant weight loss. They also had an increase in the level of "good" cholesterol (as part of HDL - high-density lipoproteins), thereby improving their cardiometabolic parameters.

An approximate diet of this diet includes:

1. High-fat dairy products: sour cream, heavy cream and yogurt, cream cheese.

2. Various oils: olive, butter, coconut.

3. Meat and poultry.

4. Fish and seafood.

5. Eggs.

6. Nuts are low in carbs.

7. Seeds.

8. Non-starchy vegetables.

In addition, it is recommended to drink at least six to eight glasses of water a day.

Reducing carbohydrate intake leads to a decrease in glucose levels (and, accordingly, insulin), which activates the mechanisms of lipolysis - that is, the breakdown of fat and the utilization of its components as an energy source.

Allowed and prohibited products

In case of violation of carbohydrate metabolism and obesity accompanying it, it is necessary to exclude:

• Bakery products and pasta.

• Various sweeteners, including honey and dates.

• Dried fruits.

• Sweets, marshmallows, marshmallows, marmalade, marshmallows, chocolate.

• Chips, crackers and other food waste.

• Semi-finished products, including dumplings and pizza.

• Margarine.

• Soy products.

• Freshly squeezed juices (pure sugar and zero fiber).

• Fruit smoothies.

• Ready sauces: ketchup, mayonnaise, mustard and others.

• Alcohol.

• Low fat or low fat foods.

• Ready-made breakfast mixes and instant cereals.

The diet must include:

1. Protein Sources: Add meat, poultry, fish, and organ meats.

   It is important to consider that even with an adequate intake of the proper amount of protein, comorbidities from the gastrointestinal tract will worsen and inhibit its absorption.

    

   In particular, the low acidity of gastric juice negatively affects the process of assimilation, the symptoms of which are:

   • Heartburn.

   • Bloating.

   • Belching.

   • Increased gas formation.

2. Sources of carbohydrates - focus on complex ones:

   • seasonal vegetables: salad, leafy, olives, asparagus, green onions, parsley / dill, artichokes, cabbage, eggplant, tomatoes, zucchini, green beans, peppers;

   • nuts;

   • unsweetened fruits and berries;

   • seaweed.

   Recommended

   "Simple and complex carbohydrates" Read more

   In small quantities allowed:

   • legumes (soaked overnight);

   • tuberous (yam, carrots, onions, beets, Jerusalem artichoke, celery root, potatoes);

   • raw (unpasteurized) honey.

3. Sources of healthy fats:

• Ghee butter and butter.

• Coconut oil.

• Olives, black olives and quality olive oil.

• Avocado.

• Hard cheese.

• Fatty varieties of fish and meat.

• Macadamia nut.

Foods to be careful with

1. Sources of omega-6 polyunsaturated fatty acids with pro-inflammatory effects:

   • margarine;

   • hydrogenated or partially hydrogenated oils;

   • any oils pressed from seeds (rapeseed, soybean, corn, linseed, sesame, grape, sunflower), if they were made at the factory. If they were pressed without high temperatures and you know who made them and how, such oils are available in limited quantities.

2. Dairy products - stimulate the secretion of insulin and insulin-like growth factor-1, which can further aggravate the already disturbed carbohydrate metabolism.

3. Sweeteners: It's not just about replacing refined sugars with a healthier alternative, it's about breaking the addiction entirely. In addition, numerous studies show that the now popular agave syrup and maple syrup are no worse than fructose provoke fatty liver.

Myths about carbohydrates in the human diet

1. Carbohydrates should not be eaten in the evening.

   This judgment is applicable to fast sugars - indeed, it is highly desirable to transfer their consumption to the first half of the day. For dinner, opt for complex carbohydrates, such as grilled vegetables.

2. Carbohydrates make you fat - this is partly true, but it all depends on the amount and type of carbohydrates eaten. It is impossible to put fiber sources and, say, chocolates on the same scale.

3. The brain needs glucose—in fact, although nervous tissue prefers to use this monosaccharide as an energy source, it is not the only raw material for its cellular furnaces. In particular, when carbohydrate intake is limited, ketone bodies are synthesized by the liver, which the brain begins to utilize.

4. When losing weight, carbohydrates must be completely limited - another erroneous, dangerous, but very common opinion. Restrict - yes, but not completely eliminated. So, say, red blood cells are able to utilize only glucose - they simply do not have mitochondrial stoves.