Writer Sonia Rafiq
“The process of taking in food, essential for growth and health is called Nutrition”
Nutrients are the chemical substances that are found in food used by the body to provide energy, maintain structure, and regulate chemical processes.
Nutritional stages are:
There are more than 40 different types of nutrients in food that can generally be divided into the following 7 groups:
3. Dietary Fiber
Classification of essential nutrients
These nutrients can be divided as either macronutrients (nutrients that are needed in large amounts) or micronutrients (nutrients that are needed in smaller quantities)
Macronutrients are carbohydrates, fats, fiber, proteins, and water.
Micronutrients are minerals and vitamins
In this section, we’ll discuss the classification of nutrients in detail.
‘Macro’ means large; as their name shows that these are the nutrients that are needed in large amounts.
Classes of Macronutrients
There are three classes of macronutrients:
Water is also a macronutrient because you require a large amount of water but unlike the other macronutrients, it doesn’t produce energy.
Why Are They Essential?
These substances are required for the supply of energy and growth for metabolism and so many other body functions.
Metabolism is the process that is involved in the generation of energy and all the ‘building blocks that are required to maintain the body and its other functions.
Macronutrients are also a source of calories but the amount of calories provided varies, depending on the food source.
For example, Each gram of carbohydrate provides four calories whereas fat provides nine calories for each gram.
As their name shows that ‘micro’ means small so micronutrients are the nutrients that are needed in only small amounts but they’re still important for carrying out bodily functions.
They include minerals and vitamins.
There are 13 important vitamins and 16 essential minerals.
Difference between micronutrients and Macronutrients
As compared to macronutrients, micronutrients are not a source of energy, but they help in the process of energy metabolism as components of enzymes that are known as coenzymes.
To stay healthy, you need to eat a balanced diet that is a mixed diet consists different foods which contain the exact amount of nutrients.
In this section, we are going to discuss 6 types of macronutrients and their classification in a bit more detail.
Macronutrients in detail
Carbohydrates are molecules that are consist of carbon, hydrogen, and oxygen.
They are also known as energy-giving foods. They give energy in the form of calories that the body needs to support other functions.
Carbohydrates are required in large quantities. About 65% of our energy comes from carbohydrates. They are the body’s main source of fuel because they can easily be converted into energy that is in the form of glucose, which all tissues and cells of our bodies use.
Sources of Carbohydrates
The main sources of carbohydrates are bread, wheat, potatoes, maize, rice, cassava,, pasta, macaroni, banana, sweets, sugar cane, sweet fruits, and honey. Other foods like vegetables, nuts, and seeds contain carbohydrates but in a lesser quantity.
Classification of carbohydrates
Carbohydrates are further classified into two groups depending on their chemical structure: simple carbohydrates. They are often called simple sugars.
Complex carbohydrates include fiber, starch, and glycogen.
Depending on the number of sugar units, carbohydrates are divided into three groups; these are:
Monosaccharides and disaccharides
Monosaccharides and disaccharides are known as simple sugars or simple carbohydrates that our body can easily utilize. Why people with diabetes mellitus should avoid these carbohydrates.
Examples are sugar, honey, sweet fruits, and sugar cane.
Polysaccharides are also called complex carbohydrates. They are needed to be broken down into simple sugars to be used by our body.
Examples: Starch and cellulose.
Proteins are large molecules composed of chains of amino acids. Amino Acids are simple subunits that are made of carbon, oxygen, hydrogen, and nitrogen.
About 10–35% of calories should come from protein. Proteins are very important for growth, especially they have great importance for children, teens, and pregnant ladies as well as to improve immune functions. They also play a vital role in making essential hormones and enzymes, in tissue repair, preserving lean muscle mass, and supplying energy when carbohydrates are not available.
Proteins have significant importance for pregnant women who need protein to build their bodies and that of the babies and placentas that is essential to make extra blood and for fat storage. Breastfeeding mothers also need protein to make breastmilk.
Sources of protein
The main sources of proteins are meats, eggs, breastmilk, beans, lentils, fish, cheese, and milk.
Especially animal foods contain more protein than plants. Although plant proteins are not that much good for body-building as animal proteins they can become more effective nutritionally when both of them are mixed with each other.
Meat is also a good source of protein
Fats and oils
Fats and oils are concentrated sources of energy that’s why they are important nutrients for young children as they’d a lot of energy-rich food. Fats also make meals more delicious and satisfying. Fat is found in meat, milk products, butter, avocado, cooking oils, fish and fats, cheese, and groundnuts.
Classification of Fats
Fats are further classified into saturated and unsaturated fats.
They are usually solid at cool temperatures. Too much use of saturated fat is not good for a person’s health because it can lead to heart and blood vessel problems.
They are liquid at room temperature. Such kind of fats is considered healthy fats.
Examples are fats from oilseeds, maize oil, groundnut, and breastmilk.
Plant sources of fats are good for a person’s health than animal sources because animal fats contain more saturated fats.
There is another nutrient that we should have in large quantity and that is water. Water does not contain carbon but yes it consists of two hydrogens and one oxygen per molecule of water.
According to a study a 50 kg adult contains about 31 liters of water whereas a one-year-old child with 10 kg weight contains nearly 8 liters of water. Almost every part of the body contains large amounts of water.
People can live without food for a few weeks but without water, for more than a few days they can’t survive. An adult needs about 2–3 liters of water daily.
Water is crucial for life. We need water for so many reasons:
- To make cells and fluids such as tears, digestive juices, and breastmilk
- To maintain body processes — most take place in water
- To keep the lining of the mouth, eyelids, and lungs wet and healthy
- To produce urine that carries waste from the body.
Dietary fiber is the indigestible part. M is found in plants. It helps maintain sugar, promotes gastrointestinal health, and prevents constipation. Dietary fiber can be further divided into the soluble and insoluble fiber.
Sources of Fiber
Sources of fiber are vegetables like cabbage and carrots, fruits like banana and avocado; peas and beans, and whole-grain cereals.
Fiber should be added to the diet for the following reasons:
- They make blood bulky that can help a person who is overweight to eat less food
- They make the faces soft and bulky that can help prevent constipation
- Fiber slows the absorption of nutrients, which helps nutrients to enter the bloodstream slowly. This is important for patients with diabetes mellitus.
In this section we have learned about the classification of nutrients in carbohydrates fats, proteins, water, and fiber as well as their importance that how they help in the nourishment of the body. Now we will learn more about vitamins and minerals that are very important micronutrients.
Micronutrients in detail
Minerals are the substances that are basically needed to ensure the health and proper working of soft tissues, fluids, and skeleton.
Examples of minerals are calcium, iron, iodine, fluorine, phosphorus, potassium, zinc, selenium, and sodium.
Vitamins are also called protective foods. They are groups of related substances that are present in small quantities in foodstuffs which play a vital role in proper body functioning.
Classification of vitamins
Vitamins are divided into two groups:
Fat-soluble vitamins are A, D, E, and K. They are soluble in fats and fat solvents. They are insoluble in water. So these are used only when there is enough fat in the body.
They include vitamins B and C, and folic acid. They are soluble in water and cannot be stored in the body.
Sources of Micronutrients
Fruits and vegetables are the best sources of micronutrients in our diets. They both contain important vitamins and minerals. Animal sources of food are also good sources of micronutrients. To ensure good health a balanced diet is very important that includes plenty of fruits and vegetables.