Nutrition:
Nutrition is the study of nutrients from both plants and animals, and the body’s subsequent handling of them for energy, growth, and development.
Nutrition can determine our quality of life. It can largely determine how we look, feel and work. Nutrition also focuses on how people can use dietary choices to reduce the risk of diseases, what happens if a person gets too much or too little of a nutrient and how different nutrients are used by the body to do various functions.
Essential Nutrients:
Food contains nutrients which are then used by the body. Nutrients are absorbable components of food. The nutrients that food must supply are known as essential nutrients. When used with reference to nutrients, the word essential means more than just necessary, it means it must be obtained from outside the body as our body cannot produce it on its own.
The 6 essential nutrients are:
1. Carbohydrates
2. Protein
3. Fats
4. Vitamins
5. Minerals
6. Water
In the body, the first three of the above nutrients can be described as “macronutrients”. Macronutrients means nutrients which we need in large amounts. Carbohydrates, proteins & fats are macronutrients which provide energy to the body.
1 gram of carbohydrate= 4 kilocalories.
1 gram of protein= 4 kilocalories
1 gram of fat= 9 kilocalories.
They can also be termed as organic. Organic nutrients contain carbon, hydrogen, and oxygen. Vitamins and minerals are known as “micronutrients” which means we require it in less amounts. However, it doesn’t mean that they are less important for the body. Micronutrients does not provide us energy but helps in the release of energy from macronutrients and helps in various physiological process of the body which keeps us healthy and disease free. Vitamins are organic nutrient whereas minerals are inorganic as they do not contain carbon. The last nutrient is water which can also be termed as a “forgotten nutrient” as there are many few people who remember to drink water in adequate amounts. Water is the largest component of our body and roughly 60-70% of our body is made up of water. Water does not contain carbon hence it is termed as an inorganic nutrient. Water does not give us energy, but it is very important for us to drink water and stay hydrated throughout the day for our body to function efficiently.
These six essential nutrients can be consumed by eating a balanced diet which contains different types of foods from all food groups like vegetables, eggs, lean poultry & meat products, fish, non-fat/low fat dairy products, pulses & legumes, whole grains, nuts & seeds, fats & oils and water.
Macronutrients:
1. Carbohydrates
Carbohydrate is a macronutrient which is made up of different molecules of sugar. It mostly contains sugars, starches & fiber. Carbohydrates are primary source of energy for the body. It provides fuel to brain & nervous system, red blood cells and muscles in the body. The fiber in carbohydrate promotes healthy digestion, stable blood glucose and normal cholesterol levels.
1 gram of carbohydrate provides 4 kilocalories of energy.
Healthy sources:
Some healthy sources of carbohydrates are non-starchy and starchy vegetables, fruits, pulses & legumes, whole-grain cereals, and non-fat/low fat dairy products.
2. Protein
Protein is a macronutrient made up of 20 different amino acids. 9 of them are essential amino acids which we need from diet or supplement and the rest of the 11 amino acids are non-essential which our body can manufacture on its own. Protein is important for building tissues like muscle, skin, hair, nails, bones, ligaments,
cartilage and for making enzymes, hormones & antibodies.
1 gram of protein provides 4 kilocalories of energy.
Healthy sources:
Some healthy sources of protein are lean meat & poultry products, fish, eggs, non-fat/low fat dairy products, pulses & legumes, and nuts & seeds.
3. Fats
Fat is a macronutrient which is made up of fatty acids and glycerol. It is a much more concentrated source of energy when compared to carbohydrates and protein. Fat acts as a secondary source of energy to the body and helps in the absorption of fat-soluble vitamins (A, D, E & K), builds cell membranes, supports healthy heart & brain functioning, gives satiety, produces sex hormones, synthesizes vitamin-d, makes bile acids & helps in healthy reproductive & immune function.
1 gram of fat provides 9 kilocalories of energy.
Healthy sources:
Some healthy sources of fats include fatty fishes like salmon and tuna, nuts & seeds, avocado, olive oil & coconut oil.
Micronutrients:
1. Vitamins
Vitamins can be further classified as either water-soluble or fat-soluble vitamins. There are total 13 vitamins out of which 9 are water-soluble vitamins and 4 are fat-soluble vitamins. Vitamin-b1, b2, b3, b5, b6, b7, b9, b12 & vitamin-c are water soluble vitamins which means they are stored in the water molecules inside the body and should be replenished daily. Vitamin-a, d, e & k are fat-soluble vitamins which are stored in the liver, fatty tissue and skeletal muscle and are released whenever needed by the body.
Some important functions of vitamins include immune system function, collagen synthesis, blood clotting, red blood cell production, absorption of calcium & iron, brain & nervous system functioning and for energy metabolism.
Each of the 13 vitamins have different functions in the body and should be consumed adequately through diet or supplementation for optimal health.
Healthy sources:
Vegetables, fruits, whole grain cereals, pulses & legumes, lean meat & poultry products, eggs, fish, low-fat/non-fat dairy products, and nuts & seeds.
2. Minerals:
16 Minerals are classified into two groups. 1) Major minerals or Macro minerals and 2) Minor minerals or Trace minerals. 7 major minerals include calcium, phosphorous, sodium, chloride, potassium, magnesium & sulfur. 9 trace minerals include selenium, zinc, iron, iodine, copper, manganese, fluoride, molybdenum & chromium. Some important functions of minerals include fluid balance, nerve transmission, muscle contraction & relaxation, bone & teeth development, hemoglobin synthesis, oxygen transport & immune system function.
Each of the 16 minerals have various physiological functions in the body and should be consumed adequately through diet or supplementation for optimal health.
Healthy sources:
Vegetables, fruits, whole grain cereals, pulses & legumes, lean meat & poultry products, fish, eggs, low-fat/non-fat dairy products, and nuts & seeds.
Water:
Water is essential and the largest component of the body. Roughly 60-70% of the body is water depending on the muscle to adipose tissue ratio. Water acts as a universal solvent and makes many solutes available for cell function. It is a major part of body fluids like blood, lymph, digestive enzymes, mucous etc. It helps in proper digestion, absorption, and excretion. It maintains fluid balance between intra cellular and extra cellular fluids and helps maintain core body temperature.
At least 12-16 glasses of water should be consumed on a daily basis and should be increased for people involved in heavy physical activity and people living in hot climates.
Summary:
Nutrition is the study of nutrients from plants & animals. Carbohydrates, protein, fats, vitamins, minerals, and water are six essential nutrients which our body needs to function efficiently. It is important to get all of them in adequate amounts by consuming a balanced diet which contains different types of foods from all food groups and drinking enough water throughout the day.
