Nutrients are substances needed for growth, energy provision and other body functions. Macronutrients are those nutrients required in large amounts that provide the energy needed to maintain body functions and carry out the activities of daily life. There are 3 macronutrients – carbohydrates, proteins, and fats.
We need energy to enable growth and repair of tissues, to maintain body temperature and to fuel physical activity. Energy comes from foods rich in carbohydrate, protein, and fat. 
Protein should consist of about 10 to 35 percent of your diet. Amino acids are the building blocks of protein. They are linked together in complex formations. There are 20 different amino acids, 9 of which are considered essential because our bodies cannot produce them naturally, and therefore they must be obtained through the diet. Proteins crucial role in the body includes building, maintaining and repairing body tissue. It is especially important to physically active individuals whose muscle tissue is constantly in need of repair.
The misconception about fat is that it is always bad for you. In fact, fat is essential for maintaining a healthy body. Your diet should consist of about 20 percent fat. The trick is to eat more of the good fats and less of the bad fats. Saturated and trans fats should be avoided while increases levels of unsaturated and the essential fatty acids, such as omega 3 and omega 6, can be good for you.
Carbohydrates are the main energy source of the body. They are chains of small, simple sugars that are broken down and enter the body as glucose. Glucose is essential for the body, as it is the preferred source of energy in our brain, heart, and central nervous system. For this reason, your diet should consist of at least 45 to 65 percent carbohydrates.
Carbohydrates are found in many foods. However, you should stay away from sweet foods with excess sugar. Instead, opt for healthier options like fruits, vegetables, beans, and nuts, as well as whole grains.