Macronutrients In Diet Plans

Nutrients are divided into two major classes, macronutrients and micronutrients, based on how much of them you need to eat on a daily basis. Macronutrients are needed in much larger amounts than micronutrients, although it is imperative to note that the importance of these nutrients is not determined by recommended intake. The macronutrients include carbohydrates, protein and fat.

Carbohydrates

The main role of carbohydrates is to supply the body with energy. When you eat carbohydrates, your body breaks them down into the simple sugar glucose, which is the default source of energy for your body -- the energy source it draws on first. Complex carbohydrates also provide various vitamins and minerals, as well as fiber and phytochemicals, which help keep you healthy. Plant-based foods, such as grains, nuts, legumes, fruits and vegetables, are the main source of carbohydrates in the diet.

Protein

Proteins make up the structural foundation of every cell in your body. Proteins also help keep your immune system healthy, transport various substances through your cell membranes, help build enzymes and hormones, and play a role in maintaining the acid-base balance in your body. Proteins also act as an energy source in the absence of carbohydrates. The richest sources of protein are animal-based foods, such as meat, poultry, fish, dairy products and eggs. Nuts and beans also provide a significant amount of protein.

Fat

Although fat has a bad reputation, it actually plays a number of important roles in your health. Fat provides you with insulation, which helps your body maintain body temperature. Fat also acts as a cushion to keep your major organs safe from harm. Without the presence of dietary fat, you would not be able to absorb and store the fat-soluble vitamins A, D, E and K. Fat can also provide you with energy in between meals when your body does not have access to carbohydrates. Different types of fats affect your body differently, however. Saturated fats, which are found in full-fat dairy products, cheese and fatty cuts of meat, are thought to promote heart disease. Most of the fat you eat should come from unsaturated fats, which can be found in vegetable oils, seeds and nuts.

Amounts

The daily recommendations for the macronutrients are given as an acceptable macronutrient distribution range, or AMDR. The AMDR represents the percentage of your total calories that should come from a specific macronutrient. According to "Nutrition and You" by Joan Salge Blake, if you consume the macronutrients within the recommended ranges, you should meet your nutrient needs and reduce your risk of developing certain chronic disease. Carbohydrates and proteins each provide four calories per gram. The AMDR for carbohydrates is 45 to 65 percent of your daily calories and the AMDR for protein is 10 to 35 percent. Fats should comprise 20 to 35 percent of your daily calorie intake.