Micronutrient

Micronutrients are the vitamins and minerals needed in milligram or microgram amounts each day. They supply no energy, but the body uses them to make enzymes, hormones and other molecules needed for normal growth, development and immunity. Apart from vitamin D, which skin can make in sunlight, the body cannot produce them, so they must come from food, fortified products or supplements.

Vitamins are organic compounds, while minerals are inorganic elements, split into major minerals such as calcium and potassium and trace minerals such as iron, zinc, copper and iodine. A shortage of a single micronutrient can cause serious disease. Iron deficiency is a leading cause of anemia, iodine deficiency disrupts thyroid hormone production and can harm the developing brain, vitamin A deficiency is a leading preventable cause of blindness in children, and a shortage of folate around conception makes neural tube defects, spina bifida among them, more likely.

These deficiencies, sometimes called hidden hunger, fall hardest on young children and pregnant women in low- and middle-income countries. Public health responses include more varied diets, fortifying staple foods, such as adding iodine to salt, and targeted supplements.