I stressed in a previous entry on macronutrients that carbohydrates, fats, and proteins are all essential components of a healthy diet. But some other substances found in food - vitamins, minerals, and trace elements called micronutrients - are equally important for a balanced diet.
Micronutrients are crucial to maintaining health but, as their name implies, are needed in only very small amounts. While these substances do not provide the body with energy, they do help it produce the hormones and enzymes needed for normal function, growth, and development.
Just about any vitamin or mineral required in small amounts by the body (generally less than 100 milligrams per day) can be considered a micronutrient. Here are just two of many important micronutrients that we may take for granted:
Vitamin A, with a recommended daily intake of 900 micrograms per day, is typically found in yellow, dark orange, and green fruits and vegetables such as oranges, sweet potatoes, and spinach, and in animal sources like liver, eggs, and kidneys.
In addition, most fat-free milk products and dried nonfat milk solids sold in the United States are fortified with vitamin A to replace the amounts lost when the fat is removed. When adding vitamin A to your diet, it is important to remember that animal sources of vitamin A are better absorbed and used more efficiently by the body than plant sources of vitamin A. Vitamin A plays an important role in vision, bone growth, and immune system health.