In scientific language, proteins (proteins) are high-molecular organic substances consisting of amino acids. Proteins are found in absolutely all cells of our body, most often they account for 50% of dry mass. Proteins are complex molecules that can participate in a wide variety of interactions and connections. We can say that these are “bricks” that act not only as a building material, but also as a carrier of other substances and even as a “conductor” in complex chemical reactions.

Every protein is made up of amino acids. There are 21 amino acids in the human body, but only 8 of them are vital, and therefore are called essential. These are valine, leucine, isoleucine, lysine, methionine, threonine, tryptophan, phenylalanine. A person is not able to synthesize them on his own, so he must receive them from food.

Why do we need squirrels?

In addition to building material for muscles, proteins perform many other functions in our body.

Protection. Antibodies that help the immune system defend against viruses and bacteria are precisely immunoglobulin proteins.

Regulation. Proteins produce elements necessary for the regulation of many systems in our body.

Transport. Hemoglobin is a transport protein that carries oxygen and carbon dioxide throughout the body.

Energy function. Proteins can act as a source of energy in the absence of sufficient fats and carbohydrates.

In general, not a single reaction occurs in our body without the participation of proteins.

Types of proteins

Depending on their origin, proteins are divided into animal and plant. By the way, the former have a more balanced amino acid composition, so we can say that vegetarians are slightly depleting their diet. But the advantage of plant-based ones is that they are much easier and faster absorbed by our body and do not contain cholesterol.

Main sources of animal protein: meat, fish, dairy products, eggs. If we talk about quantity, the champions are hard cheese (23.4 g of protein per 100 g of product) and meat (18.9 - 20.7 g depending on the variety).

The main sources of plant protein: soy, nuts, legumes, cereals and whole grains. In terms of the amount of protein, soybeans lead here (34.9 g), followed by peas and beans (20.5 and 21 g, respectively); other plant products contain noticeably less protein.

A complete diet should contain a combination of plant and animal proteins.

Protein norm

The recommended daily intake of protein varies from person to person and can be calculated using the formula: 0.84 g per kilogram of body weight. But if you lead an overly active lifestyle or are seriously involved in sports, then the daily intake can be safely increased to 1.6 - 1.8 g per kilogram. This will increase the process of its synthesis in the muscles. If you plan to reduce the amount of fatty tissue in the body, then the daily protein intake can be increased to 2 g per 1 kg of body weight.

In some sports sources you can find information about 3-4 g of protein per kilogram of weight. Allegedly, only with such an amount can truly high-quality muscle growth be ensured. Take, for example, a weightlifter weighing 90 kg. He needs to eat 360 g of protein per day, which in terms of food is approximately 1.7 kg of turkey fillet, more than 50 eggs or 12 liters of milk. We see that it is almost impossible to get such an amount with food, which is why athletes are offered to take special supplements.

But scientists are ready to argue, and urge you not to include so much protein in your diet. The diet of an average person will allow you to reach the norm of 1.4 - 1.8 g; more is not required. And according to American experts, their population consumes too much protein, and this is also not good.

Arginine and alanine, which are conditional (that is, non-essential) amino acids, are most often found in protein shakes. They are presented to us as an additional source of protein, but in fact they are absolutely useless; a balanced diet will allow you to consume more protein than a shake with this composition. In addition, sports nutrition often contains a huge number of other additives and substances that can be hazardous to health. We wrote more about this

If you need protein supplements, it is better to choose those that contain branched chain amino acids (BCAA). It contains some of the essential amino acids (leucine, valine and isoleucine). If you are unable to get the required amount of protein from food, then this supplement will help increase its synthesis in the body and fight fatigue during training. Important: taking protein will be justified only in case of serious sports activities; in all other situations, it would be more correct to simply reconsider your usual diet.

Protein harm

Protein is indeed very important for our body, but, as with everything, moderation is important here. Excess can cause serious harm. For example, excess protein in the diet increases the risk of kidney stones. This is especially important for people who have certain kidney problems; before going on a high-protein diet, they should definitely consult their doctor. A large one-time dose of protein entering the body is especially harmful to the kidneys. Therefore, it is better to change your diet gradually.

Another danger of high amounts of protein in the body is dehydration, but this can be solved by drinking plenty of water throughout the day.

An excess of protein in the body may also be associated with an increased risk of osteoporosis; the situation is aggravated if, against the background of this, too little calcium enters the body. But this applies mainly to animal proteins, but soy protein, on the contrary, protects our bone tissue from damage.

A Yale University study found that too much protein can seriously increase the risk of stomach and bowel cancer. At the same time, consuming plant protein, on the contrary, reduced this risk. These accusations mainly concern red meat (beef and pork), so experts recommend limiting the amount of it on your table.

If you need to eat a lot of protein, give preference to plant sources; this will definitely not harm your health. However, you shouldn’t completely give up animal protein either. Let us repeat that your diet, first of all, should be balanced.

There is no scientifically proven and proven harm from consuming large amounts of protein yet, since not much research has been done on this topic, but there is definitely no benefit to consuming too much. The same statement is true for both fats and carbohydrates. Remember that your body’s resources in terms of the speed of absorption and breakdown of proteins are not at all limitless, and if you constantly test them for strength, health problems cannot be avoided.

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Three fashionable American diets

The abundance of modern diets makes it possible for everyone to choose a nutritional style to suit their taste. Today we will introduce you to three more new American diets that are rapidly gaining popularity.

Anti-food-snob diet

This is not a diet in the generally accepted sense, but rather an attitude towards diet. A few years ago, Dr. Mehmet Oz released a sensational article on food. He stated that there is no point in spending money on expensive organic or farm products. Properly frozen foods contain no less vitamins, minerals and nutrients, so it is better to give preference to them. The author explained that proper nutrition can be inexpensive and accessible, the main thing is to constantly remember the simple rules.

• Choose shock-frozen products and study the ingredients on the label
• Don't eat meat more than 4 times a week; give preference to chicken or turkey.
• Limit the amount of sweets in your diet and look for healthier types, such as peanut butter.

The main idea of ​​such nutrition is that modern methods of freezing and preserving foods allow you to preserve the maximum usefulness in them. Just learn to read labels, and the cost of your diet can decrease significantly.

The Low Fodmap Diet

The main ideas of this healthy diet were formulated by Dr. Sbu Shepard. They consist in excluding from the diet foods that lead to fermentation and bloating. First of all, these are carbohydrates.

Initially, the list includes cabbage, mushrooms, apples, milk, honey, but over time you can expand it, focusing on your own well-being. As a result, you will normalize your metabolism, forget about irritable bowel syndrome and become the owner of a flat stomach.

But what can you replace forbidden products with? Let's try to figure it out

Lactose is present in almost all dairy products and the body of many adults is unable to properly digest this protein. You can replace milk in your diet with plant-based milk, hard cheeses and unpasteurized yogurt.

Fructose is present in many fruits and fruit juices, so you need to find safer varieties. These are blueberries, strawberries, bananas, melon and cranberries.

Legumes They have high nutritional value, but it is still better to limit their consumption. You can replace them with rice, oats, quinoa, wheat, barley.

Food polyols(sugar alcohols) are present in a number of diet products labeled “sugar-free.” Instead, it is better to use maple syrup, molasses, and traditional sugar in small quantities.

Cinch!

The name of this diet can be translated as “grab.” Its author, Cynthia Sass, proposed a new way to combat excess weight in 30 days. The diet begins with a five-day restriction to 5 foods: raspberries, spinach, almonds, eggs and yogurt. Then you will gradually expand your diet and include new foods in it. At the end of the diet you will be able to afford meat and fish. It is also important to exercise during this time. But the main goal is not just to lose weight, but to learn how to properly shape your diet and pay attention to nutrition. The author promises that after a 30-day marathon, you will no longer eat fast food and will begin to approach nutrition more meaningfully.

Three main rules of this diet:

• Eat according to the clock. Breaks should not exceed 3-5 hours; regular meals help speed up metabolism and promote better digestion of food.
• Maintain a balance of nutrients. Every meal should contain protein, fat, carbohydrates and fiber. The absence of at least one will have a bad effect on digestion.
• Use natural spices. They will not only add flavor to dishes, but also speed up metabolism.

Is it possible to cure candidiasis with diet?

Candidiasis (thrush) is a fairly common fungal infection that requires mandatory treatment. But some experts are convinced that with this pathology it is enough to simply follow a certain diet.

Products that provoke the proliferation of Candida yeast are sugar, gluten, alcohol and certain dairy products, so it is recommended to exclude them in case of fungal diseases. However, scientific research has not yet proven the therapeutic effect of this type of nutrition.

Candida includes more than 100 different types of yeast that live on the skin, mouth, intestines, vagina and throat. In small quantities, fungi do not cause any harm to health, but if they grow too actively, then unpleasant symptoms and manifestations occur.

So, signs of oral thrush may be the following: white spots on the mucous membranes, inflammation, dry mouth, pain when eating and swallowing.

Signs of vaginal thrush: itching and soreness, redness, pain when urinating, thick and white discharge with an unpleasant odor.

A diet for candidiasis first of all instructs patients to exclude the potentially dangerous foods and drinks that we listed above. It is also recommended to add vegetables, probiotics, sources of healthy fats, and lean protein. These foods reduce inflammation and reduce the concentration of fungi, primarily in the intestines.

A 2017 study found that too much glucose triggers the growth of Candida fungus, so cutting out sweets should theoretically help reduce the amount of fungus in the body.

And the authors of a review published in 2015 found that simple sugars and dairy products with a high percentage of lactose can activate the growth and reproduction of Candida because they lead to a change in pH in the gastrointestinal tract. But to accurately confirm the hypothesis, additional experiments are required.

As for the ban on gluten, it can damage the intestinal mucosa, which means changing its microbiota. A gluten-free diet is useful for patients with intolerance or celiac disease, but scientists have not yet confirmed its effectiveness against candidiasis.

Scientists tried to check how this or that nutritional system affects the growth of Candida in animal cells, but these studies cannot be applied to people, so the effectiveness of the diet described above has not yet been scientifically confirmed.

What can you eat if you have candidiasis: vegetables, unsweetened fruits, lean protein, fermented foods, nuts and seeds, kefir and yogurt, probiotics and natural sugar substitutes.

What not to eat if you have candidiasis: starchy vegetables, sweet fruits, processed meats, gluten, milk and cheeses, refined oils and sugars, tea, coffee and alcohol.

In conditions when the body does not have enough carbohydrates, it uses fats to obtain energy, that is, it plunges into a state of ketosis. Therefore, the keto diet helps to effectively lose weight and burn excess fat in the body. Typically, the standard diet places more emphasis on animal fats, but as vegetarians and vegans eliminate certain foods from their diet, they emphasize plant sources of protein.

In a 2014 study, researchers examined the effects of the vegan Atkins diet on weight loss and health in volunteers. Participants ate either a low-carbohydrate vegetarian diet or a high-carbohydrate vegetarian diet for 6 months. As a result, those who adhered to a low-carbohydrate diet could boast of more significant weight loss. In addition to losing weight, their levels of cholesterol, low-density lipoprotein and triglycerides decreased.

This suggests that a vegan low-carb diet may reduce the risk of cardiovascular disease. Other benefits include a reduced risk of diabetes, hypertension and cancer.

But still, such a nutritional system has quite a lot of limitations, since it is associated with certain risks, so people should remember them when planning their diet. Possible side effects of the vegetarian keto diet include:

• Constipation (due to lack of fiber)
• Kidney stones
• Decreased blood pressure
• Poor diet.

It is also worth remembering that an unbalanced vegan keto diet can cause a lack of certain vitamins and minerals in the body: calcium, iron, vitamin B12, vitamin D, zinc, omega-3 fatty acids.

The diet of a vegetarian or vegan on a keto diet traditionally includes: soy milk and tofu, coconut yogurt, soy and nut cheeses, nuts and nut oils, seeds, vegetable oils, avocado, berries, fresh vegetables, kelp, stevia, fresh herbs , spices, tea and coffee.

Foods that are prohibited on the keto diet due to their high carbohydrate content: bread and baked goods, pasta, cereals, starchy vegetables, legumes, fruits and juices, sauces, processed foods, alcohol, sugary drinks.

If you decide to follow a vegetarian version of the keto diet, try to plan your diet very carefully and first discuss the possibility of such a diet with your doctor.

On the one hand, of course, the desire of men and women, regardless of age, to meet certain criteria of beauty, in terms of building and shaping their own body, is strongly encouraged. Some approach this with full responsibility, consulting with professional fitness trainers and working under their guidance and supervision, others rely on their own superficial knowledge and proceed from the widespread opinion that the main thing in this matter is protein, and the more you consume, the better. In such situations, as a rule, people do not bother themselves with any calculations, stock up on all kinds of protein products and supplements and eat them without measure.

What is the opinion of scientists about protein consumption? Are there any restrictions on this?

In the NSCA sports nutrition guide, in order to gain lean muscle mass, it is recommended that, along with a caloric excess within 10-15% of the norm, consume 1.3 - 2 g/kg of body weight per day of protein.

During a period of active reduction in fat percentage, for example, when preparing bodybuilders for competitions, scientists allow an increased protein intake of up to 1.8 - 2 g/kg body weight per day. If the goal is to reduce the fat percentage to minimum limits, then protein consumption can be increased to 2.3 - 3.1 g/kg body weight, and the lower the fat percentage, the more protein is required.

How does the body react to increased protein intake?

This primarily concerns the kidneys. If the kidneys are absolutely healthy, then there are no problems. If there are questions, then protein intake definitely needs to be controlled. The norm should be increased to the maximum permissible level gradually, and not according to the principle “take more and throw further away.” Although there is no specific scientific basis, it seems reasonable to recommend increasing water intake with increased protein intake to reduce the risk of developing urolithiasis.

A short-term study lasting only a week showed that urea, creatine, and albumin levels in the urine of active male athletes were within normal limits when protein intake was within the recommended range (1).

A similar conclusion was reached for postmenopausal women (2).

An experiment involving nurses also confirmed the findings, with the caveat that there was no kidney disease and the assumption that non-dairy animal proteins were more harmful to the body than others (3).

Studies in mice in which protein comprised 35–45% of their daily diet suggest that excessive protein intake may cause functional changes and kidney damage (4 – 8).

An experiment on healthy people showed that doubling protein consumption, from 1.2 g/kg body weight to 2.4 g/kg body weight, causes protein metabolism in the blood to exceed the norm. At the same time, an increase in the rate of glomerular filtration was noted, but this adjustment of the body was not enough to equalize the levels of uric acid and urea in the blood within a week (9).

Thus, based on the studies conducted, we can conclude that a sharp increase in protein consumption invariably leads to negative consequences, while a gradual increase in the volume of protein consumption over a long period of time does not cause any deterioration in kidney function (10).

People with kidney problems should limit their protein intake, although uncontrolled consumption can worsen the condition (11, 12).

How does excess protein affect the liver?

Experiments on healthy rats showed that protein included in the main diet does not in any way affect the functioning of the liver. However, significantly increased amounts of protein consumed after a fast for 2 days can cause serious liver injury. When treating liver diseases, it is necessary to reduce protein intake, which is associated with the accumulation of ammonia in the blood and contributes to the development of hepatic encephalopathy (13, 14, 15).

An experiment on one experimental animal showed that liver damage can be traced during a cyclic alternation of 5 days of normal protein intake and insufficient protein intake (16).

A similar result was obtained when consuming food with a casein content of up to 40-50% after a 2-day fast (17).

How does excess protein affect bones?

An analysis of a large observational study found no relationship between protein intake and bone density, which is associated with bone fractures. However, although weak, there is still a risk when, with increased protein intake in the diet, calcium intake is reduced below 400 mg/1000 kcal (26, 27, 28).

Soy protein appears to have an additional bone protective effect in postmenopausal women due to the isoflavones present in soy (30).

Sources

1. Poortmans JR, Dellalieux O Do regular high protein diets have potential health risks on kidney function in athletes. Int J Sport Nutr Exerc Metab. (2000)
2. Beasley JM, et al Higher biomarker-calibrated protein intake is not associated with impaired renal function in postmenopausal women. J Nutr. (2011)
3. Knight EL, et al The impact of protein intake on renal function decline in women with normal renal function or mild renal insufficiency. Ann Intern Med. (2003)
4. Brändle E, Sieberth HG, Hautmann RE Effect of chronic dietary protein intake on the renal function in healthy subjects. Eur J Clin Nutr. (1996)
5. King AJ, Levey AS Dietary protein and renal function. J Am Soc Nephrol. (1993)
6. Dietary protein intake and renal function
7. Wakefield AP, et al A diet with 35% of energy from protein leads to kidney damage in female Sprague-Dawley rats. Br J Nutr. (2011)
8. Aparicio VA, et al Effects of high-whey-protein intake and resistance training on renal, bone and metabolic parameters in rats. Br J Nutr. (2011)
9. Frank H, et al Effect of short-term high-protein compared with normal-protein diets on renal hemodynamics and associated variables in healthy young men. Am J Clin Nutr. (2009)
10. Wiegmann TB, et al Controlled changes in chronic dietary protein intake do not change glomerular filtration rate. Am J Kidney Dis. (1990)
11. Levey AS, et al Effects of dietary protein restriction on the progression of advanced renal disease in the Modification of Diet in Renal Disease Study. Am J Kidney Dis. (1996)
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