Nutrition and health: what do we eat

Chapter 1: Macronutrients – the basis of our existence

1. 1 Squirrels: Building blocks of life

   Proteins, also known as proteins, play a key role in every cell of our body. They are fundamental building blocks for fabrics, organs, enzymes, hormones and antibodies. Without sufficient protein consumption, the body cannot function normally, recover and grow.

   • Amino acids: bricks of protein
     Proteins consist of amino acids, 20 of which are important for the human body. Nine of these amino acids are called indispensable (or essential), because the body cannot synthesize them independently, and we must receive them from food. These indispensable amino acids include: histidine, isolacin, leucine, lysine, methionine, phenylalanine, Treonin, Triptofan and Valin. The remaining 11 amino acids are called replaceable (or non -essential), since the body can produce them from other sources.

   • Protein functions in the body
     The functions of proteins are extensive and vital:

     • Structural function: Collagen, keratin and elastin are structural proteins that provide support and structure of the skin, hair, nails, bones and cartilage.
     • Enzymes: Proteins act as enzymes that catalyze biochemical reactions in the body. They accelerate digestion, metabolism and other critical processes.
     • Hormones: Many hormones, such as insulin and growth hormone, are proteins. They regulate many physiological functions, including blood sugar, growth and development.
     • Transport: Proteins transport substances throughout the body. Hemoglobin, for example, tolerates oxygen in the blood, and lipoproteins transport fats.
     • Immune function: Antibodies (immunoglobulins) are proteins that help protect the body from infections, identifying and neutralizing foreign substances, such as bacteria and viruses.
     • Socratic function: Case and myosine are proteins responsible for muscle contraction, providing movement.

   • Sources of protein in food
     Proteins can be found in various products of animal and plant origin.

     • Animal sources: Meat (beef, pork, poultry), fish, eggs and dairy products (milk, cheese, yogurt) are excellent sources of full protein containing all nine essential amino acids.
     • Plant sources: Legumes (beans, lentils, chickpeas), tofu, pace, film, nuts and seeds are good sources of protein for vegetarians and vegan. However, some plant proteins can be incomplete, that is, they lack one or more essential amino acids. It is important to combine various plant sources of protein in order to get all the necessary amino acids. For example, a combination of legumes (lesin) and grain (methionine) provides a full protein.

   • Protein consumption recommendations
     The recommended daily protein (RSN) protein is approximately 0.8 grams per kilogram of body weight for adults. However, the need for protein can vary depending on the age, level of activity, state of health and goals. Athletes, pregnant women and people who recover after illness or injury may require more protein. Protein deficiency can lead to loss of muscle mass, weakening of immunity and growth retardation. Excessive protein consumption, especially from animal sources, may be associated with an increased risk of kidney diseases and certain types of cancer.

   • Protein and weight control
     Protein plays an important role in weight control. It contributes to saturation, reducing the feeling of hunger and helping to control the consumption of calories. Protein also requires more energy for digestion, assimilation and metabolism (thermal effect of food) than carbohydrates or fats, which can contribute to a slight increase in calories.

2. 2 Carbohydrates: the main energy source

   Carbohydrates are the main source of energy for the body. They break down into glucose, which is used by nutrition cells. Carbohydrates are contained in a wide range of food products, including fruits, vegetables, grain and dairy products.

   • Classification of carbohydrates
     Carbohydrates can be classified into simple and complex.

     • Simple carbohydrates: Include monosaccharides (glucose, fructose, galactose) and disaccharides (sucrose, lactose, maltose). They are quickly absorbed and can cause a rapid increase in blood sugar. Sources of simple carbohydrates include sugar, honey, fruits and dairy products.
     • Complex carbohydrates: Include oligosaccharides and polysaccharides (starch and fiber). They are absorbed more slowly than simple carbohydrates, and provide a more stable energy source. Sources of complex carbohydrates include whole grain products, vegetables and legumes.

   • Glycemic index (GI) and glycemic load (GN)
     Guy is a measure of how quickly the product increases blood sugar. High GI products quickly increase blood sugar, and low GI products do it slower. The GN takes into account both the gut of the product and the amount of carbohydrates in a portion. GN is a more accurate measure of the effect of food on blood sugar than gi. The choice of products with low GI and GN can help control blood sugar, maintain healthy weight and reduce the risk of chronic diseases.

   • Fiber: indigestible, but vital carbohydrate
     Fiber is a type of carbohydrate that is not digested by the body. It is found in plant products, such as fruits, vegetables, whole grain products and legumes. Fiber plays an important role in maintaining the health of the digestive system, regulating blood sugar and reduce cholesterol.

     • Soluble fiber: Dissolves in water, forming a gel -like substance. Helps reduce cholesterol and control blood sugar. Sources include oats, apples, citrus and legumes.
     • Insoluble fiber: It does not dissolve in water and adds volume to the chair. Helps prevent constipation and maintain the regularity of the chair. Sources include whole grain products, bran and vegetables.

   • The role of carbohydrates in the body
     Carbohydrates perform many important functions in the body:

     • Energy: The main source of energy for cells, especially for the brain and muscles.
     • Saving protein: Enough consumption of carbohydrates allows the body to use protein to restore and growth of tissues, and not for energy production.
     • Noter health: Fiber supports a healthy digestive system and prevents constipation.
     • Blood sugar regulation: Fiber slows down sugar into the blood, helping to maintain a stable blood sugar.

   • Sources of carbohydrates in food
     Carbohydrates are contained in a wide range of food:

     • Grain: Rice, wheat, corn, oats, barley, Kinoa. It is important to choose whole grains, as they contain more fiber and nutrients than refined grains.
     • Fruits: Apples, bananas, berries, oranges, pears and others.
     • Vegetables: Potatoes, carrots, broccoli, spinach and others.
     • Legumes: Beans, lentils, chickpeas.
     • Dairy products: Milk, yogurt.

   • Recommendations on carbohydrate consumption
     The recommended carbohydrate consumption is 45-65% of the total number of calories per day. It is important to choose complex carbohydrates with a high fiber content and limit the consumption of simple carbohydrates, especially added sugars. Excessive consumption of simple carbohydrates can lead to weight gain, increased blood sugar and an increase in the risk of developing chronic diseases.

3. 3 Fat: the necessary source of energy and much more

   Fats, also known as lipids, are an important macronutrian necessary for the health and normal functioning of the body. They are a concentrated source of energy, provide organs depreciation, help to absorb fat -soluble vitamins and participate in the production of hormones. However, not all fats are the same. It is important to choose healthy fats and limit the consumption of harmful fats.

   • Fat classification
     Fat can be classified into saturated, unsaturated and trans fats.

     • Saturated fats: Usually solid at room temperature. They are mainly contained in animal products, such as meat, dairy products and eggs. Excessive consumption of saturated fats can increase the level of LDL cholesterol (poor cholesterol) and increase the risk of developing cardiovascular diseases.
     • Unsaturated fats: Usually liquid at room temperature. Contained in vegetable oils, nuts, seeds and fish. Unsaturated fats are divided into mono -saturated and polyunsaturated.
       • Mononasized fats: Useful for the health of the heart. Contained in olive oil, avocados and nuts.
       • Paul -Eathed out fats: It is necessary for the body and should come from food. Omega-3 and omega-6 fatty acids are polyunsaturated fats.
         • Omega-3 fatty acids: They have an anti -inflammatory effect and are useful for the health of the heart, brain and eyes. Contained in fatty fish (salmon, tuna, sardines), linen seeds, chia seeds and walnuts.
         • Omega-6 fatty acids: Important for growth and development. Contained in vegetable oils (sunflower, corn, soybean). It is important to maintain the balance between the consumption of omega-3 and omega-6 fatty acids.
     • Transjir’s: Artificially created fats formed during the hydrogenation of vegetable oils. Contained in some processed products, such as pastries, fried foods and margarine. Transfiders increase LDL cholesterol and reduce the level of HDL cholesterol (good cholesterol), significantly increasing the risk of cardiovascular disease. Most countries currently limit or prohibit the use of trans fats in the food industry.

   • Fat functions in the body
     Fat perform many important functions in the body:

     • Energy: Concentrated energy source.
     • Assimilation of vitamins: Necessary for the assimilation of fat -soluble vitamins (a, d, e and k).
     • Organs protection: Provide the depreciation and protection of organs.
     • Hormone production: Participate in the production of hormones.
     • Cell structure: Are an important part of cell membranes.
     • Taste and saturation: Improve the taste of food and contribute to saturation.

   • Sources of fat in food
     Fat contained in various foods:

     • Animal sources: Meat, dairy products, eggs.
     • Vegetable oils: Olive oil, coconut oil, avocad oil, sunflower oil, corn oil, soy oil.
     • Nuts and seeds: Almonds, walnuts, chia seeds, linen seed, sunflower seeds.
     • Avocado:
     • Fat fish: Salmon, tuna, sardins, mackerel.

   • Fat consumption recommendations
     Recommended fat consumption is 20-35% of the total number of calories per day. It is important to give preference to unsaturated fats, limit the consumption of saturated fats and avoid trans fats. Choose useful sources of fat, such as olive oil, avocados, nuts, seeds and oily fish.

Chapter 2: Micronutrients – small, but important assistants

2. 1 Vitamins: vital compounds

   Vitamins are organic compounds necessary in small quantities to maintain health and normal functioning of the body. They are not produced by the body (or produced in insufficient quantities), so we should receive them from food or additives. Vitamins are involved in many biochemical processes, including metabolism, immune function and cell growth.

   • Classification of vitamins
     Vitamins are divided into two main groups: fat -soluble and water -soluble.

     • Fat -soluble vitamins: Dissolved in fats and stored in the body, mainly in the liver and adipose tissue. Fat -soluble vitamins include vitamins A, D, E and K. Excessive consumption of fat -soluble vitamins can lead to toxicity, as they can accumulate in the body.
       • Vitamin A: It is important for vision, immune function, cell growth and skin health. Contained in carrots, sweet potatoes, spinach, liver and eggs.
       • Vitamin D: It is important for bone health, the absorption of calcium and immune function. It is produced in the skin under the influence of sunlight. Contained in oily fish, egg yolks and enriched products. Vitamin D deficiency is widespread, especially in the winter months and in people with limited stay in the sun.
       • Vitamin E: Antioxidant that protects cells from damage by free radicals. Contained in vegetable oils, nuts, seeds and green leafy vegetables.
       • Vitamin K: It is important for coagulation of blood and bone health. Contained in green leafy vegetables, broccoli and Brussels cabbage.
     • Water -soluble vitamins: They dissolve in water and are not stored in the body in large quantities. Excess water -soluble vitamins are usually excreted in urine. Water -soluble vitamins include group B vitamins (thiamine, riboflavin, niacin, panthenic acid, pyridoxine, biotin, folic acid and cobalamin) and vitamin C. It is important to regularly receive water -soluble vitamins from food.
       • B vitamins B: Participate in the metabolism of energy, the functioning of the nervous system and the formation of red blood cells. Various B vitamins are found in various foods, including whole grain products, meat, fish, eggs, dairy products, legumes and green leafy vegetables.
       • Vitamin C: Antioxidant, important for immune function, collagen formation and iron assimilation. Contained in citrus fruits, berries, pepper and broccoli.

   • The role of vitamins in the body
     Vitamins play a decisive role in many body functions:

     • Metabolism: Participate in the metabolism of carbohydrates, fats and proteins.
     • Immune function: They support the immune system and help fight infections.
     • Growth and development: Necessary for the growth and development of cells.
     • Bone health: Vitamins D and K are important for bone health.
     • Vision: Vitamin A is important for vision.
     • Antioxidant protection: Vitamins C and E protect cells from damage by free radicals.

   • Sources of vitamins in food
     Vitamins are contained in various foods:

     • Fruits and vegetables: Great sources of many vitamins.
     • Whole grain products: Contain B vitamins B.
     • Meat and fish: Contain vitamins of group B and vitamin D.
     • Dairy products: Contain vitamins A, D and B12.
     • Nuts and seeds: Contain vitamin E.

   • Recommendations for vitamin consumption
     Recommended daily consumption standards (RSN) vitamins vary depending on age, gender and health. It is important to adhere to a balanced diet rich in fruits, vegetables, whole grain products, low -fat protein and healthy fats to get all the necessary vitamins. In some cases, vitamin additives may be required, especially with vitamin deficiency or in certain diseases. Consult a doctor or nutritionist before taking vitamin additives.

3. 2 Minerals: inorganic elements for health

   Minerals are inorganic substances necessary for the health and normal functioning of the body. They are not produced by the body and should come from food or additives. Minerals are involved in many biochemical processes, including bone formation, muscle contraction, transmission of nerve impulses and maintaining the balance of fluid.

   • Classification of minerals
     Minerals are divided into two main groups: macrominerals and microminerals (or trace elements).

     • Macrominerals: Required in large quantities (more than 100 mg per day). Macrominerals include calcium, phosphorus, magnesium, sodium, potassium, chloride and sulfur.

       • Calcium: It is important for the health of bones and teeth, muscle contraction, transmission of nerve impulses and blood coagulation. Contained in dairy products, green leafy vegetables, enriched products and tofu.
       • Phosphorus: It is important for the health of bones and teeth, energy and functioning of cells. Contained in dairy products, meat, fish, eggs and nuts.
       • Magnesium: It is important for the functioning of muscles and nerves, the regulation of blood sugar, blood pressure and protein synthesis. Contained in green leafy vegetables, nuts, seeds, whole grains and legumes.
       • Sodium: It is important for maintaining the balance of fluid, transmitting nerve impulses and muscle contraction. Contained in table salt, processed products and some vegetables. It is important to limit sodium consumption, since excessive consumption can increase blood pressure.
       • Potassium: It is important for maintaining the balance of fluid, transmitting nerve impulses and muscle contraction. Contained in fruits, vegetables, legumes and dairy products.
       • Chloride: It is important for maintaining the balance of liquid and acid-base balance. Contained in table salt and many foods.
       • Sulfur: It is part of amino acids and vitamins. Contained in protein products.

     • Microminerals (trace elements): It is necessary in small quantities (less than 100 mg per day). Microminerals include iron, zinc, iodine, selenium, copper, manganese, fluorine, chrome and molybdenum.

       • Iron: It is important for the transfer of oxygen in the blood (hemoglobin) and the functioning of the immune system. Contained in meat, fish, poultry, legumes, green leafy vegetables and enriched products. Iron deficiency can lead to anemia.
       • Zinc: It is important for immune function, healing of wounds, cell growth and reproductive function. Contained in meat, seafood, nuts, seeds and legumes.
       • Iodine: It is important for the functioning of the thyroid gland and the production of thyroid hormones, which regulate metabolism. Contained in iodized salt, seafood and dairy products. Iodine deficiency can lead to thyroid diseases.
       • Selenium: Antioxidant that protects cells from damage by free radicals. It is important for the immune function and functioning of the thyroid gland. Contained in Brazilian nuts, seafood, meat and poultry.
       • Copper: Important for the formation of red blood cells, the functioning of the nervous system and the formation of bones. Contained in seafood, nuts, seeds and legumes.
       • Manganese: It is important for metabolism, the functioning of enzymes and bone formation. Contained in whole grain products, nuts, seeds and tea.
       • Fluorine: It is important for the health of teeth and bones. Contained in fluorine water and toothpaste.
       • Chromium: It is important for regulating blood sugar and metabolism of carbohydrates, fats and proteins. Contained in broccoli, mushrooms, beer yeast and whole grain products.
       • Molybden: It is important for the functioning of enzymes and metabolism of sulfur. Contained in legumes, whole grains and nuts.

   • The role of minerals in the body
     Minerals play an important role in many body functions:

     • Bone formation: Calcium, phosphorus and magnesium are important to the health of bones and teeth.
     • Muscle contraction: Calcium, magnesium, sodium and potassium are important for muscle contraction.
     • Transfer of nerve impulses: Sodium, potassium and chloride are important for transmitting nerve impulses.
     • Fluid balance: Sodium, potassium and chloride are important for maintaining the balance of liquid.
     • Metabolism: Many minerals participate in metabolic processes.
     • Immune function: Zinc, iron and selenium are important for immune function.

   • Sources of minerals in food
     Minerals are contained in various foods:

     • Dairy products: Contain calcium, phosphorus and potassium.
     • Meat and fish: Contain iron, zinc and selenium.
     • Fruits and vegetables: Contain potassium, magnesium and other minerals.
     • Whole grain products: Contain magnesium, iron and manganese.
     • Nuts and seeds: Contain magnesium, zinc and selenium.
     • Legumes: Contain magnesium, iron and zinc.

   • Mineral consumption recommendations
     Recommended daily consumption standards (RSN) of minerals vary depending on age, gender and health. It is important to adhere to a balanced diet rich in various foods in order to get all the necessary minerals. In some cases, mineral additives may be required, especially with mineral deficiency or with certain diseases. Consult a doctor or nutritionist before taking mineral additives.

Chapter 3: Water – Elixir of Life

3. 1 The role of water in the body

   Water is the most important nutrient for life. It accounts for about 50-70% of body weight and is involved in many vital functions of the body. Without water, the body cannot function normally.

   • Water functions in the body
     Water performs many important functions in the body:

     • Transport: It transports nutrients, oxygen and hormones to cells and removes waste from the body.
     • Temperature regulation: Helps adjust body temperature through sweating.
     • Lubrication: Lubricates joints and organs, facilitating movement and preventing friction.
     • Chemical reactions: Participates in many chemical reactions, including digestion.
     • Cell structure: It is an important part of cell structure.
     • Organs protection: Protects organs and tissue from damage.

   • Regulation of the water balance
     The body regulates the water balance after several mechanisms:

     • Thirst: A sense of thirst is the signal of the body about the need to make up for water reserves.
     • Kidneys: The kidneys regulate the amount of water removed in the urine.
     • Hormones: Hormones, such as vasopressin, regulate the retention of water by the kidneys.

   • Factors affecting the need for water
     The need for water varies depending on several factors:

     • Level of activity: People engaged in physical activity need more water.
     • Climate: In hot climate, the need for water increases.
     • Age: Babies and elderly people are more susceptible to dehydration.
     • Health status: Some diseases may affect the need for water.
     • Diet: A high salt or protein diet can increase the need for water.

   • Signs of dehydration
     Signs of dehydration include:

     • Thirst:
     • Dry mouth:
     • Dark urine color:
     • Dizziness:
     • Fatigue:
     • Headache:
     • Constipation:

   • Sources of water
     Water can be obtained from various sources:

     • Drinking water: The most important source of water.
     • Other drinks: Tea, coffee, juice, milk and other drinks also contain water.
     • Food: Fruits and vegetables contain a significant amount of water.

   • Water consumption recommendations
     General recommendations for water consumption are about 8 glasses (2 liters) per day. However, individual needs may vary. It is important to drink enough water during the day, especially during and after physical activity. Focus on the color of urine – it should be light yellow.

Chapter 4: digestion – how the body processes food

4. 1 Stages of digestion

   Digestion is the process of splitting food into smaller molecules that the body can learn and use to obtain energy, growth and recovery. Digestion includes several stages that occur in various organs of the digestive system.

   • The role of the digestive system
     The digestive system is responsible for:

     • Eating:
     • Mechanical grinding of food:
     • Chemical splitting of food:
     • Nutritional absorption:
     • Removing waste:

   • The organs of the digestive system
     The main organs of the digestive system include:

     • Mouth: The beginning of the digestive tract. The food is chopped with teeth and mixed with saliva. The saliva contains an amylase enzyme that begins to split starch.
     • Esophagus: The tube connecting the mouth to the stomach. Food moves through the esophagus in the stomach through peristalsis (wave -like muscle contractions).
     • Stomach: The muscular organ in which the food is mixed with gastric juice containing hydrochloric acid and pepsin enzyme. Solic acid helps to break down proteins and kills bacteria. Pepsin breaks down proteins into smaller peptides.
     • Small intestine: The main body of digestion and absorption of nutrients. The small intestine consists of three departments: duodenum, spinning intestine and ileum. In the duodenum, the food is mixed with bile (produced by liver and stored in the gall bladder) and pancreatic juice (produced by the pancreas). Bile emulsifies fats, facilitating their digestion. Pancreatic juice contains enzymes that split carbohydrates, proteins and fats. The walls of the small intestine are lined with villi and microse, which increase the surface area for the absorption of nutrients.
     • Bulshose intestines: In the large intestine, water and electrolytes are absorbed. The undigested food remains and waste turn into feces. The large intestine contains bacteria that help break down the fiber and produce some vitamins (for example, vitamin K).
     • Rectum: The final section of the large intestine, where feces are stored before defecation.
     • Anus: The hole through which the feces are excreted from the body.
     • Liver: It produces bile necessary for digestion of fats. Plays an important role in the metabolism of nutrients.
     • Gall bladder: Keeps bile.
     • Pancreas: It produces pancreatic juice containing enzymes that split carbohydrates, proteins and fats. Also produces insulin and glucagon that regulate blood sugar.

   • Digestive process
     Digestion includes the following processes:

     • Mechanical digestion: Grinding with teeth, peristalsis in the esophagus and stomach contractions.
     • Chemical digestion: Food splitting with enzymes.
     • Suction: Nutrients are absorbed into the blood through the walls of the small intestine.
     • Removing: The undigested food remnants and waste are excreted from the body through the anus.

   • Digestive enzymes
     Enzymes play a key role in chemical breakdown of food:

     • Amylase: It breaks down starch into simpler sugars.
     • Proteases (Pepsin, Tripsin, Hyotripsin): The proteins are split into amino acids.
     • Lipase: It breaks down fats into fatty acids and glycerin.
     • Lactase: It breaks down lactose (milk sugar) into glucose and galactose.

   • Factors affecting digestion
     Various factors can affect digestion:

     • Food: Fatty food is digested longer than carbohydrate.
     • Age: With age, digestion can slow down.
     • Health status: Some diseases can affect digestion.
     • Stress level: Stress can affect the digish