How are nutrients used by the body?
by Neila Forssberg
This is the original form of the article as it appeared on Answers.com.
The body uses three main nutrients to function — carbohydrates, protein, and fat. When we ingest food, the digestion process starts. The body breaks foods down into nutrients and uses those nutrients for energy, growth and cell repair.
Essential nutrients are compounds that the body can’t produce at all or can’t produce in sufficient quantities. Therefore, these nutrients must come from food.
While there are many essential nutrients, they can be divided into two categories: macronutrients and micronutrients.
Macronutrients are eaten in large amounts and provide your body with energy. They include the primary building blocks of your diet — protein, carbohydrates, and fat.
Vitamins and minerals are micronutrients, and small doses go a long way. There are six main groups of essential micronutrients and macronutrients: protein, carbohydrates, fats, vitamins, minerals, and water.
Protein
Protein provides the building blocks of the body, and not just for muscle. Every cell, from bone to skin to hair, contains protein.
A startling 16 percent of the average person’s body weight is from protein. Protein is used primarily for growth, health, and body maintenance.
All of your hormones, antibodies, and other important substances are composed of protein. Protein is not used to fuel the body unless necessary.
Proteins are made of up different amino acids. While the body can create some amino acids on its own, many essential amino acids can only come from food. You need a variety of amino acids for your body to function properly.
Carbohydrates
Carbohydrates are necessary for a healthy body. Carbs fuel your body, especially your central nervous system and brain, and protect against disease, according to the Mayo Clinic.
Carbohydrates should make up 45 to 65 percent of your total daily calories, according to the Dietary Guidelines for Americans.
Fats
According to Harvard Medical School, fat supports many of your body’s functions such as vitamin and mineral absorption, blood clotting, building cells, and muscle movement. The Dietary Guidelines for Americans recommend that 20 to 35 percent of your daily calories come from fat, but the World Health Organization suggests keeping it under 30 percent of your calories.
Including healthy fats in your diet can help you to balance your blood sugar, decrease your risk of heart disease and type 2 diabetes, and improve brain function. They’re also powerful anti-inflammatories, and they may lower your risk of arthritis, cancer, and Alzheimer’s disease.
Vitamins
Vitamins are vital for warding off disease and staying healthy. The body needs these micronutrients to support its functions. There are thirteen essential vitamins that the body needs to function properly, including vitamins A, C, B6, and D.
Each vitamin plays an important role in the body, and not getting enough of them can cause health problems and disease. Many Americans do not get enough of many essential vitamins. Vitamins are crucial for healthy vision, skin, and bones.
Vitamins may lower the risk of lung and prostate cancer, and they’re powerful antioxidants. Vitamins such as vitamin C boost the immune system and help the body heal.
Minerals
Much like vitamins, minerals help support the body. They’re essential for many body functions, including building strong bones and teeth, regulating the metabolism, and staying properly hydrated. Some of the most common minerals are calcium, iron, and zinc.
In addition to strengthening bones, calcium helps with nerve signal transmission, maintaining healthy blood pressure, and muscle contraction and relaxation. Iron supports your red blood cells and hormone creation, while zinc boosts your immune system and promotes wound healing.
Water
You can go for weeks without food, but you can’t last more than a few days without water. Water is absolutely crucial for every system in the body. It’s also the main thing you are made of. About 62 percent of your body weight is water.
Water improves your brain function and mood. It acts as a shock absorber and a lubricant in the body. It also helps flush out toxins, carry nutrients to cells, hydrate the body, and prevent constipation.
Even mild dehydration can make you feel tired and impair your concentration and physical performance.