Saturday, November 13, 2021

The Functions of Nutrients

Picture of a food pyramid with vegetables at the bottom and fats and oils at the top
Food Pyramid

Proteins, carbohydrates and fats are the most well-known categories of nutrients, but vitamins, minerals, fiber and water have important roles to play as well in how our bodies function.  Proteins, carbohydrates and fats are called macronutrients; vitamins and minerals are micronutrients.


     Proteins are chemicals found in all living things. They are composed of long strings of a small number of different amino acids. Different proteins have unique arrangements of these amino acids.

     Amino acids are either nonessential or essential. Nonessential amino acids can be manufactured by cells in the body; essential amino acids can not be manufactured, and must be acquired through the diet.

     Proteins have many functions in living things. They build and repair most cell and body structures. They regulate the processes that produce various chemicals in cells. They also transport the products to other places within the body.

     Protein in the diet may be from animal or plant sources. Animal-derived proteins, such as meat, milk, or eggs are reliable sources of all the amino acids necessary to sustain life. Individual plant sources of protein do not always contain all the necessary amino acids. Plant protein sources are often paired in order to provide all necessary amino acids. For example, beans and rice are a common combination.

     If you eat more protein than your body needs the excess can be metabolized to provide calories or energy.



     Carbohydrates are simpler molecules than proteins. Their chemical formulas contain only the elements carbon, hydrogen and oxygen. Their chemical names often end in ose.” Carbohydrates are either simple or complex.

     Simple carbohydrates are sugars. They may be found naturally in fruits, honey, and milk. The sugars added to refined and processed foods are also simple sugars. This form of carbohydrate is easily absorbed and metabolized for quick energy.

     Complex carbohydrates are starches. They are found in grains and products made from grains, potatoes and other vegetables. Starches can also be used by the body as energy, but must be digested first. Foods containing complex carbohydrates are often refined, removing many of the other nutrients such as vitamins, minerals and fiber, leaving only the carbohydrates.



     Fats may be in a solid or liquid form. Liquid fats are called oils. Fats from animals include fat in meat and fish, poultry, and dairy products. Fats from plants are found in nuts, avocados, and olives.

     Fats contain lots of calories and are an important source of energy in the body. Some vitamins require the presence of fats to be absorbed from the digestive system.


     Vitamins are organic compounds required in very small amounts for body processes. Different vitamins have letter names—A, B complex, C, D, E, and K.

     Vitamins help your body use the three main nutrients (carbohydrates, fats, and proteins). They are also ingredients in the production of blood cells, hormones, genetic material, and nervous system messaging chemicals. Vitamin deficiencies cause diseases such as scurvy and rickets.

     Processing many foods removes nutrients such as vitamins. Enriched or fortified foods had added vitamins to replace those lost during processing. However, fresh natural foods contain vitamins in their preferred natural state.


     Minerals are elements found in soil that are nonorganic and can not be synthesized by living organisms. They perform a variety of functions in the body.

     Calcium, phosphorous and magnesium form part of bones and teeth. Sodium, chlorine (as chloride) and potassium regulate the balance of water and other chemicals in the body; they are known as electrolytes.

     Some minerals such as copper, fluoride, iodine, iron, manganese, selenium and zinc are only needed in tiny amounts. These are called trace minerals.


     Fiber is the part of plant foods that the body doesn't absorb from the digestive tract. The two main varieties of fiber are soluble and insoluble.

     Soluble fiber is found in many fruits including citrus fruits, grains such as barley and oats, and legumes such as beans and peas. Soluble fiber slows the rise of blood sugar following digestion of carbohydrates, helps lower blood cholesterol after ingestion of fats, and adds bulk to stools.

     Insoluble fiber is found in many vegetables such as cabbage and celery, wheat bran, and whole-grain products. It stimulates the gastrointestinal tract, adds bulk to stools and helps prevent constipation.


     You may not think of water as important to nutrition, but it plays a part in almost every major body function. Water forms the basis of blood, which takes nutrients and oxygen to every cell and carries away their waste products. Water regulates body temperature, and cushions and protects joints and organs. It is involved in many of the chemical processes that take place in living cells.

    Many foods contain a lot of water, especially fruits. Watery foods are also known as low-caloric-density foods.

     It's important to fuel your body with the calories from carbohydrates, proteins and fats, which are the macronutrients. Although they do not supply calories, the micronutrients—vitamins and minerals—are necessary for the cells to carry out their chemical processes.

    Pay attention to the food you eat. Be sure you have a varied diet with adequate nutrition from all sources.

No comments:

Post a Comment

Got a Comment?