Minerals (Nutrition)

Minerals are simple substances your body needs to stay healthy. They come from rocks and soil, but you get them by eating plants and animals that took them in first. Plants pull minerals out of the ground through their roots. When you eat a carrot or drink milk from a cow that ate grass, you are getting minerals that started in the dirt.

Your body cannot make minerals on its own. You have to eat them. About 4 percent of your body weight is made of minerals. For a kid who weighs 75 pounds, that is around 3 pounds of minerals tucked inside bones, blood, muscles, and even teeth.

Scientists split minerals into two groups. Major minerals are the ones your body needs in larger amounts. These include calcium, phosphorus, potassium, sodium, magnesium, chloride, and sulfur. Trace minerals are needed in tiny amounts, but they still matter. These include iron, zinc, iodine, copper, fluoride, and selenium.

Each mineral has its own job. Calcium and phosphorus build strong bones and teeth. About 99 percent of the calcium in your body is stored in your skeleton. Iron helps your blood carry oxygen from your lungs to the rest of your body. Without enough iron, you feel tired and weak. Potassium and sodium help your nerves send signals and your muscles contract. Every time you blink or take a step, those two minerals are at work. Iodine helps a gland in your neck called the thyroid control how fast your body uses energy.

You can find minerals in lots of foods. Milk, yogurt, cheese, and leafy greens like spinach and kale are packed with calcium. Red meat, beans, and dark leafy greens give you iron. Bananas and potatoes are famous for potassium. Seafood and table salt provide iodine. Nuts and seeds carry magnesium and zinc.

Too little of a mineral causes problems, but so does too much. Too little iron leads to a condition called anemia. Too much sodium, which most people get from salty packaged foods, can raise blood pressure over many years. Doctors and scientists still debate exactly how much sodium is safe, and the answer may differ from person to person.

The best way to get the right mix is to eat a variety of foods. A plate with vegetables, fruit, whole grains, and some protein usually covers what your body needs. Pills can help when a doctor recommends them, but real food is where most of your minerals should come from.