Carbohydrates and essential fats, along with proteins, are macro-nutrients that provide the human body with its main source of energy needed for all bodily functions, including metabolic function. Carbohydrates are easy for the body to break down and use as an energy source, and essential fats are the most concentrated source of energy.
Carbohydrates are a macro-nutrient the human body needs in the largest amount each day. They are the body’s main source of fuel, used by every tissue and cell in the body after being converted to glucose for energy. Carbohydrates are needed for a properly functioning nervous system, including the brain. The kidneys and heart also rely on carbohydrates to function. Carbohydrates are also essential in the function of the digestive system and waste elimination. Healthy carbohydrates are found in foods like vegetables, beans and nuts.
There are three kinds of fat: saturated, unsaturated and trans fat. The healthiest fat comes from unsaturated fat found in olive oil, avocados and nuts. Some fat is essential for the human body to survive. Twenty-five to 35 percent of daily calories should be healthy fats, which are required for normal growth and development, energy, maintaining cell membranes and the absorption of many vitamins such as A, D and E.