Micronutrients are substances such as vitamins and minerals that are essential for healthy growth and development. Although micronutrients are required only in tiny quantities by the body, a micronutrient deficiency can cause serious problems. Vitamin A, folic acid, iodine, iron and zinc deficiencies are prevalent worldwide and can have grave consequences for children, pregnant women and women of childbearing age.
Vitamin A, or retinol, is a fat-soluble vitamin needed for good vision and healthy skin, teeth, bones and soft tissue. Vitamin A is present in red meat, liver, kidney, fish oil, eggs, dairy products and fortified foods. Beta-carotene, found in yellow and orange fruits and vegetables, as well as green leafy vegetables, is converted into vitamin A by the body. Vitamin A deficiency can lead to vision problems and increase the likelihood of infections.
Folic acid, also known as folate or vitamin B-9, is a water-soluble vitamin important for DNA synthesis, cell growth, the formation of body tissues and the prevention of birth defects. Folic acid is found in green leafy vegetables such as spinach and kale, orange juice and fortified breakfast cereals. Taking 400 mcg of folic acid daily before conception and during the early stages of pregnancy helps prevent neural tube defects in a developing baby.
Iodine is an essential mineral needed to make thyroid hormones, which are needed for healthy growth. The main dietary source of iodine is table salt, but it is also found in fish, kelp, garlic, sesame seeds, spinach and squash. An iodine deficiency can cause delayed growth and development, fatigue, weight gain, sensitivity to fluctuating temperatures and dry skin. At least 1 billion people in developing countries might be at risk for iodine deficiency, notes the University of Maryland Medical Center.
Iron is an essential mineral needed for the formation of hemoglobin, a protein present in red blood cells that transports oxygen around the body. Iron is present in red meat, liver, poultry, salmon, tuna, egg yolk, dried beans, dried fruits, whole grains, nuts and green leafy vegetables. An iron deficiency can lead to iron deficiency anemia, a condition characterized by fatigue, shortness of breath, dizziness, weight loss and headaches. Pregnant and menstruating women and young children are at increased risk of iron deficiency.
Zinc is an essential mineral required for normal growth and development, healthy skin, infection prevention and wound healing. Zinc is found in red meat, poultry, oysters, beans, nuts, whole grains and fortified breakfast cereals. A zinc deficiency might cause delayed growth and development in children and adolescents, hair loss, diarrhea, delayed wound healing, loss of appetite and weight loss. Children in developing countries who are zinc deficient might be at increased risk of infections such as pneumonia.