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What is balanced diet?Elucidate its any four constituents.

The human body needs a long list of nutrients every day. The essentials, though, are called “macronutrients,” and your body needs them to stay healthy and perform optimally. They include the following five:

1.Carbohydrates
Main function: Provide energy
“Carbohydrates are the body’s main energy source and the brain’s only source of fuel,” says Kate Patton, MEd, RD, a registered dietitian at the Cleveland Clinic in Ohio. Your body breaks carbohydrates down into glucose, which cells require to create energy.
Get more: The best sources of carbohydrates are whole grains and foods made from those grains, such as whole-wheat bread, bulgur, barley, oatmeal, brown rice, and cornmeal. Limit your intake of sugar and refined grains (including white pasta, white rice, and white breads), the U.S. Department of Agriculture (USDA) recommends.

2. Protein
Main function: Build and repair tissue
“Protein is another important source of energy for the body,” Solomon says. Protein consists of amino acids that act as the body’s main building blocks for tissues, such as muscle, skin, bone, and hair. Proteins also assist in many reactions in the body, including the production of enzymes (the catalysts that keep all body processes running smoothly), hormones, and antibodies, Solomon explains.
Get more: The best protein sources are lean meats, poultry and seafood, beans and peas, nuts and seeds, eggs, and soy products, according to the USDA.

3. Fats
Main function: Provide backup energy
“Your body uses fats for energy when carbohydrates aren’t available,” Patton says. “You also need fats as insulation, to help your body absorb fat-soluble vitamins, and to protect your organs.”
Get more: Fats come in both liquid and solid forms. The USDA notes that the best sources of healthful fats are the liquid monounsaturated and polyunsaturated fats found in olive oil, canola oil, sunflower oil, soybean oil, corn oil, nuts, seeds, and avocados, as well as fatty fish rich in omega-3 fatty acids. Limit foods high in unhealthy saturated fats (red meat, cheese, butter, and ice cream) and trans fats (processed products that contain partially hydrogenated oil), which increase your risk for disease.

4. Vitamins and Minerals
Main function: Maintain optimal health
“You need vitamins and minerals for numerous physiological functions that help you survive,” Patton says. They’re essential for normal growth and development, and each one plays a unique role in helping to maintain optimal health. For example, calcium and vitamin D a
Get more: Vitamins and minerals come from a variety of foods, including fruits and vegetables, dairy products, and lean protein sources. “Eat a selection of colorful fruits and vegetables every day, and vary the types of proteins you eat,” Solomon says.

5. Water
Main function: Enables vital bodily functions
You’ve probably heard that you can live for weeks without food but only days without water. That’s because water is the most important essential nutrient. It is involved in many of your body’s vital functions, and it distributes other essential nutrients to your cells.