This post is about three major macronutrients. There are carbohydrates, proteins, and fat.
First of all, carbohydrates are used for energy, for instant use or for later use and each gram of carbohydrates gives you four calories. When there is a lack of carbohydrates taken in, your body uses proteins for energy and may even use muscle tissues. This is why it is important to always have a good supply of carbohydrates in you; about 55-60% of your diet should be made up of carbs. Your body breaks down carbohydrates into glucose; it can be immediately used or stored as glycogen. The muscles are used to store the glycogen. The bloodstream is also used to store broken down carbohydrates called glucose. If both are filled, then the excess carbohydrates are turned to fats, where they’re stored for future usage. There are four types of carbohydrates, these including, mono-saccharides, disaccharides, polysaccharides, and fibers. First, mono-saccharides are simple sugars like glucose, fructose. They are the basic building block of carbohydrates and are the smallest forms of carbohydrates. The next type of carbohydrates, disaccharides are made of two mono-saccharides like sucrose, which is made up of glucose and fructose. The last carbohydrate is polysaccharides are made up of many mono-saccharides, healthy examples of these include starches (bread, grains, rice etc.). Another form of carbohydrates are fibers, around 20 grams of dietary fiber is necessary in our diet and you can get fiber from eating whole grain items like some cereal. Fibers are used to many things in your body from excrement elimination or for the absorption of cholesterol in the bloodstream. You may think carbohydrates are bad and make you gain weight, but they’re really important in an everyday diet.
Proteins are primarily the basic structure of living cells. They are used to make hormones, plasma, enzymes, and in some case (in the lack of carbohydrates) they are used to provide energy (four calories per gram.) Proteins are made up of amino acids strung together. There are 20 amino acids, 9 are considered essential amino acids, because your body cannot make them. A person should consume these 9 amino acids from other foods in their diet. Amino acids are critical parts of assisting the function of the Central Nervous System (CNS). Protein is broken down into all the tissues in our bodies, but the liver and muscles use most of these. Proteins that contain the 9 essential amino acids are called complete proteins, while ones that don’t are called incomplete proteins. Meats, milk, cheese fish and eggs are all complete proteins. Examples of incomplete proteins are vegetables, grains, nuts, and seeds. Although you can eat different types of incomplete proteins to gain all nine of the essential amino acids, hence eating one incomplete protein for breakfast and one for lunch is comprised of a completed protein. Proteins are used to build tissues and/or as energy storage. When a person fasts, the body can break down the tissues, muscles and even organs as an energy source. Protein intake is determined by the individual and daily activities you perform. Tissue growth is determined to injury, weight training, or pregnancy. If you don’t eat enough proteins, your body can go through hair loss and/or brittle and discolored fingernails. The muscles in your body will start to weaken and decrease in size and your body won’t be as strong. Your diet should consist of roughly 15-20% proteins.
The last macronutrient is fat, fats are required to produce cell membranes, body fats, bile, steroids and vitamin D. Fats are made of glycerol and fatty acids. Body fat is important for the body temperature regulation (insulation). Fats also are used to transport and absorb vitamins, to supply energy (9 calories per gram) when there is a shortage of carbs, and to aid in skin growth and conservation. Fat molecules are made up of a glycerol backbone and several fatty acid chains. About 25-30% of you diet should be made up of them. Fats are digested in the small intestines, they then are transported through the blood and stored as glycerol and other fatty acids in fat cells. When they are needed, they are released into the bloodstream as fatty acids for energy. You may think that fats, essentially make you fat. But fats are actually essential to survive. If you eat no fats, this leads to severe internal as well as external problems. Fats control chemicals that manage blood pressure, contractions (child birth), blood clots, gut motion and your immune system. These chemicals are only manufactured as needed. Cholesterol is closely related to fats, it is important for producing cell membranes, sex hormones, bile and vitamin D. Although cholesterol is good for the maintaining of the body, too much cholesterol can be very hazardous to you. You should maintain the amount of fats you eat as too much can result in your arterial walls being clogged. HDL is the good cholesterol, it transports cholesterol to the liver, while LDL is caused by large intake of saturated fats and puts you at risk of heart disease. Unsaturated fats consists of two groups, monounsaturated fats, and polyunsaturated. The monounsaturated fats have been shown to actually lower the chance of heart disease. Arteriosclerosis is when your arteries are clogged, this can lead to a decrease of blood flow and can cause blood clots. If your arteries become too clogged, the blood stops flowing to your heart and you can die of a heart attack. Cardiovascular health is good and proper diet helps protect from this. Some of the healthiest foods that you can find fat in are dairy products like milk and some cheese. Fat can be found in many other healthy foods also though but in much smaller amounts.
Overall, a good intake of each macronutrient is good for your body. The body needs all the macronutrients to retain good health. This is because carbohydrates, proteins and fats all contain different types of nutrients your body needs to survive.
http://www.shapefit.com/macronutrients.html
http://www.dietitian.com/fatlower.html