MacronutrientsMacronutrients are nutrients that provide calories or energy. Nutrients are substances needed for growth, metabolism, and for other body functions. Since “macro” means large, macronutrients are nutrients needed in large amounts, these are; carbohydrates, protein and fat.
CarbohydratesCarbohydrate is a macronutrient that our bodies need in the largest quantity.
We need carbohydrates for:
• Fuel- they are the body’s main fuel source
• Proper functioning of the central nervous system, kidneys, brain, Red Blood Cells and muscles (including the heart)
• Energy storage in the liver and muscles
• Intestinal health and waste elimination
Carbohydrates are mainly found in grains and starches like rice, beans, breads, pastas, starchy vegetables such as potatoes, peas, corn and yams, fruits, milk, yogurt and sugars. Carbohydrates provide four calories per gram.
ProteinMost Americans get plenty of protein, and easily meet this need by consuming a balanced diet.
We need protein for:
• Growth (especially important for children, teens, and pregnant women)
• Tissue repair
• Immune function
• Making essential hormones and enzymes
• Energy when carbohydrates aren’t available
• Preserving lean muscle mass
Protein is found in meat, poultry, fish, meat substitutes, cheese, milk, nuts, and legumes. It can also be found to a lesser degree in starchy foods and vegetables. When we eat these types of foods, our bodies break down the protein in them and form amino acids (the building blocks of protein). Some amino acids are essential, which means that we need to get them from our diet. Others are nonessential, meaning our body can make them. Protein that comes from animal sources contains all of the essential amino acids that we need. Plant sources of protein, on the other hand, do not contain all of the essential amino acids, which is why it important for vegetarians to combine vegetable proteins to ensure all needs are met. Proteins provide four calories per gram.
FatAlthough fats have received a bad reputation for causing weight gain, some fat is essential for survival.
We need fat for:
• Normal growth and development
• Energy (fat is the most concentrated source of energy)
• Absorbing certain vitamins (vitamins A, D, E, K, and carotenoids)
• Providing cushioning for the organs
• Maintaining cell membranes
• Providing taste, consistency, and stability to foods
Fat is found in meat, poultry, nuts, milk products, butters and margarines, oils, lard, fish, and grain products. There are three main types of fat: saturated fat, unsaturated fat, and trans fat. Saturated fat (found in meat, butter, lard, and cream) and trans fat (found in baked goods, snack foods, fried foods, and margarines) have been shown to increase your risk for heart disease. Replacing saturated and trans fat in your diet with unsaturated fat (found in foods like olive oil, avocados, nuts, and canola oil) has been shown to decrease the risk of developing heart disease. Fat provides 9 calories per gram.
Although macronutrients are very important, they are not the only things needed for survival. Our bodies also need water and micronutrients. Micronutrients are nutrients that our bodies need in smaller amounts. They come from vitamins and minerals. You can obtain your vitamin and mineral needs by eating a wide variety of foods from all of the food groups. Your RD can assist you in meeting your micronutrient needs and will decide if you are a candidate for a supplement pill.