Nutrition Glossary

An A to Z of everyday nutrition terms

Nutrition has its own vocabulary, and a clear definition often removes the mystery from a food label or a diet plan. This glossary explains the terms you will meet most often across NNWA (Nutrition & Wellness Academy) courses and in day-to-day Indian nutrition, in plain language. Where relevant, definitions follow the ICMR-NIN (Indian Council of Medical Research, National Institute of Nutrition) Dietary Guidelines for Indians.

• Amino acid: the building blocks of protein. Some are essential, meaning the body cannot make them and must obtain them from food such as pulses, dairy and eggs.
• Antioxidant: a compound that helps protect the body's cells from damage by unstable molecules called free radicals; found in fruits, vegetables and many spices.
• Balanced diet: a diet that supplies energy and all essential nutrients in the right proportions, built around cereals, pulses, vegetables, fruit, dairy and healthy fats.
• Basal metabolic rate (BMR): the number of calories the body needs at complete rest to keep vital functions running, such as breathing and circulation.
• Body mass index (BMI): a simple screening number calculated from weight and height, used to categorise underweight, healthy weight, overweight and obesity at a population level.
• Calorie: a unit of energy in food. The calorie shown on food labels is technically a kilocalorie (kcal), the energy that fuels every activity.
• Carbohydrate: a macronutrient and the body's main energy source, found in cereals, millets, pulses, fruit and vegetables; grouped into simple and complex carbohydrates.
• Cholesterol: a fatty substance the body needs in small amounts; dietary patterns influence blood levels of low-density (LDL) and high-density (HDL) cholesterol.
• Dietary fibre: the indigestible part of plant foods that supports digestion and gut health; found in whole grains, millets, pulses, fruit and vegetables.
• Dietitian: a qualified professional who assesses, diagnoses and treats diet-related conditions. In India this requires a relevant degree and Indian Dietetic Association (IDA) registration.
• Electrolyte: a mineral such as sodium, potassium or chloride that carries an electrical charge and helps regulate fluid balance, nerve signals and muscle function.
• Enzyme: a protein that speeds up chemical reactions in the body, including the digestive enzymes that break food down into absorbable nutrients.
• Essential nutrient: a nutrient the body cannot make in sufficient amounts and must get from food, including certain amino acids, fatty acids, vitamins and minerals.
• Glycaemic index (GI): a ranking of carbohydrate foods by how quickly they raise blood glucose; low-GI foods such as whole pulses and millets release energy more gradually.
• Glycaemic load (GL): a measure combining a food's glycaemic index with the amount of carbohydrate in a serving, giving a fuller picture of its effect on blood glucose.
• Hydration: the state of having enough water in the body to support temperature control, circulation, digestion and the transport of nutrients.
• Macronutrient: a nutrient the body needs in large amounts for energy and structure, namely carbohydrate, protein and fat.
• Metabolism: the sum of all chemical processes that convert food into energy and building materials for the body.
• Micronutrient: vitamins and minerals the body needs in small amounts; deficiencies, such as iron or vitamin B12, can affect health significantly.
• Mineral: an inorganic nutrient such as calcium, iron, iodine or zinc, needed for bones, blood, hormones and many other functions.
• National Credit Framework (NCrF): an Indian framework that brings school, higher and vocational education onto a single credit scale, so credits can be earned and accumulated across learning routes.
• Nutritionist: a professional who advises on food and healthy eating. The title is not statutorily protected in India, so qualifications and scope vary; nutritionists do not provide clinical medical nutrition therapy unless separately qualified.
• Obesity: a condition of excess body fat that raises the risk of several health problems; assessed using measures such as body mass index and waist circumference.
• Prebiotic: a type of dietary fibre that feeds beneficial gut bacteria; found in foods such as onion, garlic, banana and whole grains.
• Probiotic: a live beneficial micro-organism, found in foods such as curd (dahi), that supports a healthy balance of gut bacteria.
• Protein: a macronutrient made of amino acids, needed to build and repair tissues; sources include pulses, dairy, eggs, soya, fish and meat.
• Recommended dietary allowance (RDA): the average daily intake of a nutrient judged enough to meet the needs of most healthy people, as set for Indians by ICMR-NIN.
• Registered Dietitian (RD): a dietitian who has met the education, training and examination standards of the Indian Dietetic Association (IDA) and holds RD registration.
• Saturated fat: a type of fat, mostly from animal foods and some oils, that is usually solid at room temperature; guidelines advise keeping intake moderate.
• Trans fat: an unhealthy fat formed when oils are partially hydrogenated; FSSAI (Food Safety and Standards Authority of India) limits its use in the food supply.
• Vitamin: an organic micronutrient needed in small amounts for normal function; grouped into fat-soluble (A, D, E, K) and water-soluble (B-complex and C) vitamins.
• Whole grain: a grain that keeps all its natural parts (bran, germ and endosperm) such as whole wheat, brown rice, bajra and jowar, retaining more fibre and nutrients.

To go deeper than definitions, the Diploma in Nutrition, Dietetics & Public Health and NNWA's short courses teach how these concepts fit together in real Indian diets.