Nutrition Glossary
Learn the key terms in dietetics, nutrition and health. Every definition prepared by e-dietetyk.com specialists.
Nutrition basics
BMI (Body Mass Index)
A ratio of body weight (kg) to height squared (m). Used for initial assessment of whether body weight is within a healthy range. Values: <18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight, ≥30 obese. Does not account for body composition (muscle vs fat mass).
BMR (Basal Metabolic Rate)
The minimum amount of energy (kcal) the body needs at rest to maintain vital functions — breathing, circulation, thermoregulation. Calculated based on sex, age, body weight and height (e.g. Harris-Benedict or Mifflin-St Jeor equation).
TDEE (Total Daily Energy Expenditure)
Total daily energy requirement, calculated as BMR multiplied by the physical activity level (PAL). Accounts for daily activities, exercise and the thermic effect of food. The basis for setting diet calorie targets.
Caloric balance
The difference between energy consumed from food and energy expended by the body. A positive balance (surplus) leads to weight gain, a negative balance (deficit) to weight loss. A zero balance maintains current weight.
Caloric deficit
A state where you consume fewer calories than your TDEE. A safe deficit is typically 300–500 kcal/day, allowing loss of 0.5–1 kg per week. An excessive deficit can lead to muscle loss and metabolic slowdown.
Caloric surplus
A state where you consume more calories than your TDEE. A controlled surplus (200–400 kcal/day) is used for muscle building. An uncontrolled surplus leads to fat tissue gain.
Diet
A way of eating — the overall pattern of food products and eating habits. In a clinical context: a planned menu tailored to individual health needs, goals and preferences. Diet is not only about weight loss — it also includes therapeutic, sports and preventive diets.
Nutrition plan
A detailed menu for a set period (e.g. a week, a month) containing specific meals, recipes, product weights and nutritional values. At e-dietetyk.com, plans are generated by AI and verified by a clinical dietitian.
Macronutrients
Protein
A building macronutrient — made of amino acids, essential for building and repairing muscles, producing enzymes and hormones, and immune function. Daily requirement: 0.8–2.0 g/kg body weight (depending on activity). Sources: meat, fish, eggs, dairy, legumes, tofu.
Simple carbohydrates
Easily absorbed sugars — glucose, fructose, sucrose. They raise blood glucose levels quickly (high glycemic index). Sources: sugar, honey, sweets, white bread, fruits. Should make up no more than 10% of daily energy.
Complex carbohydrates
Polysaccharides (starch, glycogen) — digested more slowly, providing stable energy. They have a lower glycemic index than simple sugars. Sources: groats, wholegrain bread, brown rice, potatoes, legumes.
Saturated fats
Fatty acids with no double bonds in the carbon chain. Excess raises LDL cholesterol levels and increases cardiovascular disease risk. Sources: butter, lard, fatty meats, palm oil, coconut oil. Recommended intake: <10% of daily energy.
Unsaturated fats
Fatty acids with one (monounsaturated, MUFA) or multiple (polyunsaturated, PUFA) double bonds. Beneficial for the cardiovascular system. Sources: olive oil, avocado, nuts, oily fish. Includes omega-3 and omega-6 fatty acids.
Fibre (dietary fibre)
An indigestible fraction of carbohydrates — regulates bowel movements, supports gut microbiota, lowers cholesterol and stabilizes blood sugar. Daily requirement: 25–40 g. Sources: vegetables, fruits, whole grains, seeds, legumes.
Essential amino acids
Amino acids the body cannot produce on its own — they must come from the diet. There are 9: leucine, isoleucine, valine, lysine, methionine, phenylalanine, threonine, tryptophan, histidine. Complete sources: meat, eggs, dairy, soy, quinoa.
Omega-3 fatty acids
Polyunsaturated fatty acids (EPA, DHA, ALA) with anti-inflammatory effects. Support brain, heart and nervous system function. Sources: oily fish (salmon, mackerel, sardines), flaxseed, walnuts, rapeseed oil. Recommended: 250–500 mg EPA+DHA daily.
Micronutrients
Iron (Fe)
A micronutrient essential for oxygen transport (haemoglobin) and energy production. Deficiency leads to anaemia. Haem iron (meat, fish) is better absorbed than non-haem iron (legumes, spinach). Vitamin C enhances iron absorption.
Calcium (Ca)
The main building material for bones and teeth, essential for muscle contractions, blood clotting and nerve conduction. Daily requirement: 1000–1200 mg. Sources: dairy, sardines, calcium-set tofu, broccoli, mineral water. Absorption requires vitamin D.
Vitamin D
A fat-soluble vitamin crucial for calcium absorption, bone health, immunity and muscle function. Synthesized in the skin under UV-B radiation. Supplementation widely recommended (800–2000 IU/day). Dietary sources: oily fish, eggs, mushrooms.
Folic acid (vitamin B9)
Essential for DNA synthesis, cell division and proper fetal development. Critical in pregnancy — deficiency increases neural tube defect risk. Recommended intake: 400 µg/day (600 µg in pregnancy). Sources: dark leafy greens, legumes, liver.
Vitamin B12 (cobalamin)
Essential for red blood cell formation, nervous system function and DNA synthesis. Found exclusively in animal products — vegetarians and vegans must supplement. Deficiency leads to megaloblastic anaemia and neuropathy. Sources: meat, fish, eggs, dairy.
Zinc (Zn)
A micronutrient involved in over 300 enzymatic reactions. Supports immunity, wound healing, taste and smell, and protein synthesis. Daily requirement: 8–11 mg. Sources: red meat, seafood (oysters), pumpkin seeds, nuts, whole grains.
Magnesium (Mg)
Involved in over 600 metabolic processes — blood pressure regulation, muscle and nerve function, protein synthesis, glucose metabolism. Deficiency manifests as muscle cramps, fatigue, irritability. Sources: nuts, seeds, dark chocolate, spinach, avocado.
Potassium (K)
An electrolyte regulating blood pressure, fluid-electrolyte balance and muscle function (including the heart). A potassium-rich diet reduces hypertension risk. Daily requirement: 3500–4700 mg. Sources: bananas, potatoes, tomatoes, avocado, legumes.
Sodium (Na)
An electrolyte essential for osmotic pressure regulation and neuromuscular function. Excess (>2000 mg/day) increases hypertension risk. Main source: table salt and processed foods. WHO recommends limiting intake to 5 g of salt/day.
Vitamin C (ascorbic acid)
A potent antioxidant, essential for collagen synthesis, non-haem iron absorption and immune function. The body cannot synthesize it. Daily requirement: 75–90 mg. Sources: bell peppers, citrus fruits, kiwi, blackcurrant, broccoli.
Indices & indicators
Glycemic index (GI)
A classification of foods by their effect on blood glucose levels after consumption, on a scale of 0–100 (glucose = 100). Low GI (<55): groats, legumes. Medium (56–69): basmati rice, rye bread. High (>70): white bread, potatoes, sweets. A key parameter in diabetic diets.
Glycemic load (GL)
Takes into account both the glycemic index and the amount of carbohydrates in a serving. Better reflects the actual impact of a meal on blood sugar than GI alone. Formula: GL = (GI × g carbs in serving) / 100. Low GL: <10, medium: 11–19, high: ≥20.
Insulin index (II)
Measures the body's insulin response to consuming a given food, independent of the glycemic index. Some foods (e.g. dairy, whey protein) trigger a strong insulin response despite a low GI. Important for managing insulin resistance.
WHR (Waist-to-Hip Ratio)
The ratio of waist circumference to hip circumference — an indicator of fat distribution. Abdominal obesity (WHR >0.9 in men, >0.85 in women) is associated with increased risk of metabolic disease, type 2 diabetes and cardiovascular disease.
Diets & health conditions
Insulin resistance
A condition where the body's cells respond poorly to insulin, leading to elevated blood glucose and insulin levels. A risk factor for type 2 diabetes, PCOS and fatty liver disease. Dietary treatment: low-glycemic diet, regular meals, fibre, physical activity.
Celiac disease
An autoimmune disease where consuming gluten (a protein in wheat, rye, barley) damages intestinal villi and impairs nutrient absorption. The only treatment: a strict lifelong gluten-free diet. Diagnosis: antibody testing + intestinal biopsy.
SIBO (Small Intestinal Bacterial Overgrowth)
Excessive bacterial growth in the small intestine, causing bloating, abdominal pain, diarrhoea and malabsorption. Treatment includes antibiotics and a low-FODMAP diet. Diagnosis: hydrogen-methane breath test.
Elimination diet
A diagnostic and therapeutic strategy involving temporary exclusion of suspected foods (e.g. dairy, gluten, eggs) from the menu, followed by gradual reintroduction to identify a food allergen or intolerance.
Ketogenic diet (keto)
A high-fat, low-carbohydrate diet (<50 g carbs/day) that forces ketosis — a metabolic state where the body uses ketone bodies as its main energy source instead of glucose. Used for epilepsy, weight loss and insulin resistance. Requires specialist supervision.
Mediterranean diet
A dietary pattern based on traditional cuisine of Mediterranean countries. Rich in vegetables, fruits, whole grains, olive oil, fish and nuts. Limits red meat and processed foods. Proven benefits: reduced risk of heart disease, diabetes and cancer.
DASH diet
Dietary Approaches to Stop Hypertension — a diet designed to lower blood pressure. Based on vegetables, fruits, low-fat dairy and whole grains. Limits sodium (<2300 mg/day), saturated fats and sugar. Clinically proven effectiveness for hypertension.
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