Encyclopedia

What You'll Find in the Nutrition Encyclopedia: Macros, Micronutrients, and Terminology

Here, we've compiled everything important about nutrition, presented clearly and comprehensibly. We will explore the fundamental building blocks of food—macronutrients and micronutrients. These include proteins, carbohydrates, fats, vitamins, and minerals. You will understand how they function in your body.

We will also explain key terms you often hear at the gym or online, such as glycemic index, the thermic effect of food, or nitrogen balance. Each definition is supported by specific numbers and facts. Our goal is to provide you with practical information that you can apply immediately.

Our aim is for this encyclopedia to become your go-to reference. Whenever you have a question about nutrition, you will find a quick and accurate answer here. No complex jargon, no confusion—just pure, useful information to help you train better and eat more mindfully.

Core Topics

Macronutrients

Macronutrients are the nutrients your body needs in large amounts. They provide energy and are the building blocks of the body. There are three main types: proteins, carbohydrates, and fats.

Proteins

Proteins are the building blocks of muscles, skin, hair, and nearly all tissues in the body. They play a key role in recovery and the regulation of many processes. They are composed of amino acids.

• Energy Value: 4 kcal/gram.
• Functions: Building and repairing tissues, producing enzymes and hormones, transporting nutrients.
• Recommended Intake: For individuals who train actively, an intake of 1.6-2.2 grams of protein per kilogram of body weight per day is recommended. This can increase to 2.5-3.0 grams per kilogram during phases of extreme caloric deficits.
• Sources: Meat, fish, eggs, dairy products, legumes, nuts, seeds.
• Nitrogen Balance: An indicator of the ratio between nitrogen intake (from protein) and nitrogen excretion. A positive nitrogen balance—consuming more than you lose—is essential for muscle growth.
• Essential Amino Acids (EAA): The nine amino acids that the body cannot produce on its own and must be obtained from food. These are: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. Leucine, isoleucine, and valine are known as branched-chain amino acids (BCAA).

Carbohydrates

Carbohydrates are the primary source of energy for the body and brain. They are broken down into glucose, which is used directly for energy or stored as glycogen in the muscles and liver.

• Energy Value: 4 kcal/gram.
• Functions: Primary energy source, support brain function, glycogen storage for intense workouts.
• Types:
  • Simple Carbohydrates: Fast-digesting, with a high glycemic index. Examples: sugar, honey, fruits.
  • Complex Carbohydrates: Slow-digesting, with a lower glycemic index. Examples: whole grains, rice, potatoes, legumes.
  • Fiber: A special type of carbohydrate that is not digested but aids in digestion and satiety. Recommended daily intake: 25-30 grams.
• Glycemic Index (GI): A measure of how quickly a food raises blood sugar levels. Foods with a high GI (above 70) cause a rapid spike, while those with a low GI (below 55) lead to a more gradual increase.
• Recommended Intake: Depends on the level of physical activity. For active individuals, it can range from 3-5 grams per kilogram of body weight to over 6-8 grams per kilogram for very intense training.
• Sources: Rice, potatoes, oats, bread, fruits, vegetables.

Fats

Fats are a concentrated source of energy and are vital for numerous bodily functions. They are involved in the absorption of fat-soluble vitamins and the production of hormones. They constitute about 20-30% of total caloric intake.

• Energy Value: 9 kcal/gram.
• Functions: Energy source, absorption of vitamins (A, D, E, K), hormone production, organ protection, thermal insulation.
• Types:
  • Saturated Fats: Found mostly in animal products. Moderate intake is advised.
  • Unsaturated Fats: Beneficial for the cardiovascular system.
    • Monounsaturated: Olive oil, avocado, nuts.
    • Polyunsaturated: Omega-3 (fish, flaxseed) and Omega-6 (vegetable oils). The ratio of Omega-3 to Omega-6 is important.
  • Trans Fats: Avoid them. They are industrially produced and harmful to health.
• Recommended Intake: Typically 0.8-1.2 grams per kilogram of body weight per day. Never go below 0.5 g/kg, as this can compromise hormonal function.
• Sources: Avocado, nuts, fish (salmon, mackerel), olive oil, coconut oil.

Micronutrients

Micronutrients are vitamins and minerals that the body needs in small amounts. They do not provide energy but are crucial for almost every biochemical process. A deficiency can lead to serious health problems.

Vitamins

Vitamins are organic compounds that the body cannot produce on its own (or in sufficient quantities) and are necessary for normal functioning. They are divided into fat-soluble and water-soluble.

• Fat-Soluble (A, D, E, K): Stored in fatty tissues and the liver. They can accumulate in the body.
  • Vitamin A: Vision, immunity. Recommended Daily Allowance (RDA): 700-900 micrograms.
  • Vitamin D: Bone health, immunity, hormonal function. RDA: 600-800 IU (15-20 micrograms).
  • Vitamin E: Antioxidant. RDA: 15 milligrams.
  • Vitamin K: Blood clotting, bone health. RDA: 90-120 micrograms.
• Water-Soluble (B-complex, C): Not stored in the body and must be consumed daily. Excess is excreted through urine.
  • Vitamin C: Immunity, skin health. RDA: 75-90 milligrams.
  • B-Vitamins: Energy metabolism, nervous system function. Examples: B1 (thiamine) – 1.1-1.2 mg; B2 (riboflavin) – 1.1-1.3 mg; B3 (niacin) – 14-16 mg; B6 (pyridoxine) – 1.3 mg; B9 (folate) – 400 mcg; B12 (cobalamin) – 2.4 mcg.

Minerals

Minerals are inorganic substances involved in many bodily functions and are necessary for bone and tooth health, nervous system function, and fluid balance. They are divided into macrominerals (needed in larger amounts) and trace minerals (needed in very small amounts).

• Macrominerals:
  • Calcium: Bones, teeth, muscle contractions. RDA: 1000-1200 milligrams.
  • Magnesium: Muscle and nerve function, energy production. RDA: 310-420 milligrams.
  • Potassium: Fluid balance, nerve impulses. RDA: 2600-4700 milligrams.
  • Sodium: Fluid balance, nerve impulses (but be cautious with excessive intake). RDA: under 2300 milligrams.
  • Phosphorus: Bones, teeth, energy metabolism. RDA: 700 milligrams.
• Trace Minerals:
  • Iron: Oxygen transport. RDA: 8-18 milligrams (depends on sex and age).
  • Zinc: Immunity, wound healing. RDA: 8-11 milligrams.
  • Selenium: Antioxidant. RDA: 55 micrograms.
  • Iodine: Thyroid gland function. RDA: 150 micrograms.

Digestion and Metabolism Terminology

Thermic Effect of Food (TEF)

This is the energy your body expends to digest, absorb, and metabolize the food you have eaten. Different macronutrients have different thermic effects.

• Proteins: Approximately 20-30% of ingested calories. The highest TEF.
• Carbohydrates: Approximately 5-10% of ingested calories.
• Fats: Approximately 0-3% of ingested calories. The lowest TEF.
• Practical Significance: Diets with a higher percentage of protein lead to a slightly increased total energy expenditure, which can aid in weight loss.

Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE)

Basal Metabolic Rate (BMR): The energy your body burns at rest to maintain its basic functions—breathing, heart rate, maintaining body temperature. This is the minimum energy required for life, not including digestion or physical activity.

Total Daily Energy Expenditure (TDEE): The total energy your body burns in one day. It includes BMR, the thermic effect of food (TEF), and the energy expended during physical activity (workouts, daily life). TDEE is the most important metric when planning caloric intake.

Nutritional Supplements – Basic Concepts

BCAA (Branched-Chain Amino Acids)

BCAAs are the three essential amino acids—leucine, isoleucine, and valine. They are unique because they are metabolized directly in the muscles, rather than the liver, and play a key role in muscle protein synthesis and reducing muscle fatigue. Recommended ratio: 2:1:1 (leucine:isoleucine:valine). An effective intake is 5 to 10 grams before, during, or after a workout.

EAA (Essential Amino Acids)

EAAs are the nine amino acids that the body cannot produce on its own and must be obtained through food or supplements. They include the BCAAs, as well as six other amino acids (histidine, lysine, methionine, phenylalanine, threonine, tryptophan). They are absolutely essential for complete protein synthesis and recovery. They have been proven to be more effective than BCAAs for stimulating muscle protein synthesis.

Who Is This Encyclopedia For?

• For fitness beginners who want to understand the fundamentals of nutrition.
• For active trainees who aim to optimize their diet.
• For anyone who wants to eat healthier and make informed choices.
• For people who want to quickly look up the meanings of terms.
• For those interested in numbers, recommended daily allowances, and energy values.

How to Use These Materials

Browse the individual articles when you have a specific question or want to learn more about a particular nutrient. Use the search bar or the table of contents to quickly find the information you need. We strive to maintain current and scientifically-backed information. Read actively, compare, and apply what you learn to your daily life.