The WHO estimates that over a third of the population in the world from sea to sea is affected by vitamin deficiencies. Vitamins are essential compounds for the body and are mostly obtained from dietary sources. Vitamins are used by the body for various functions such as cell and tissue growth and regulating metabolism.
The forms of folate are folic acid and vitamin B9. Folic acid reduces the risk of neural tube defects in pregnant women. The element promotes fertility and reduces stroke. The deficiency of folate can manifest as anemia, depression, fetal neural tube defects, confusion, brain defects during pregnancy, glossitis, fatigue, swollen tongue, mouth sores, and gray hair. Foods with the highest amounts of folate include liver, avocado, sprouts, spinach, asparagus, and Brussels sprouts. It further occurs in dairy products, fruits, dark green vegetables, seafood, grains, peas, beans, nuts, poultry, and grains.
Over 300 different enzymes present in the body need zinc to function optimally. Zinc is required for the digestive and immune systems to function properly and it also controls diabetes, improves metabolism, and reduces stress levels. Zinc is essential in protein synthesis, and it also regulates the production of cells. High concentrations of zinc are stored in the eye retina, pancreas, liver, red and white blood cells, and kidney. Meat has been identified as the primary source of zinc along with oats, oysters, whole wheat grain, almonds, peas, and turnips. Zinc deficiency symptoms include low blood pressure, depression, stunted bone growth, general growth retardation, and loss of appetite. An estimated 2.2 billion people are affected by zinc deficiency in the world.
8. Vitamin K
Vitamin K encompasses a group of compounds, the most important of which are Vitamin K1 and Vitamin K2. Vitamin K1 is acquired from leafy greens and other vegetables while K2 is mainly obtained from eggs, meat, and cheese. Vitamin K is critical in preventing excessive bleeding and is responsible for blood clotting. Vitamin K deficiency increases the risk of excessive bleeding, and a supplement may be recommended.
Magnesium is an essential mineral needed for teeth and bone structure. It takes part in more than 300 enzyme reactions, and it plays a role in preventing heart attacks, migraines, and cardiovascular diseases. Low intake of magnesium is commonly associated with diseases such as diabetes, osteoporosis, heart disease, and metabolic syndrome. A diet rich in magnesium includes dark-green vegetables, seeds, nuts, beans, avocados, and dark chocolate. 57% of the American population does not obtain the US RDA for magnesium's dietary intake.
Calcium is critical for bone maintenance, and it also mineralizes teeth and bone. The amount of calcium in the blood is strictly regulated, and the excess is stored in the bones. Calcium performs several functions as a signaling molecule and thus contributes to the healthy functioning of the body. The most common disorder of calcium deficiency is osteoporosis where the bones become soft and fragile. Good sources of this vitamin are dark green vegetables such as spinach and kale, boned fish, and dairy products. Low calcium intake is common in the elderly and young women.
5. Vitamin B12
Vitamin B12 is a water-soluble vitamin essential for nerve and brain function and blood formation. The element is almost exclusively found in animal foods such as dairy, organ meat, eggs, shellfish, and meat. The absorption of vitamin B12 in the body requires the aid of a protein named intrinsic factor. Vitamin B12 causes the blood disorder known as megaloblastic anemia where red blood cells become enlarged. In developed countries, Vitamin B12 deficiency is mostly reported among elderly populations while in developing countries, it begins in early age and persists throughout the life.
4. Vitamin D
Vitamin D is a fat-soluble type of vitamin which is present in few dietary sources. The vitamin is also produced when ultraviolet rays from the sun strike the skin and facilitate its synthesis. Vitamin D is necessary for bone growth, calcium absorption in the gut, reduction of inflammation, modulation of genes, and immune function. Lack of adequate Vitamin D in children results in soft bones, rickets, delayed growth, bone loss, and muscle weakness in adults. Dietary sources for the element include egg yolks, cod liver oil, and fatty fish. People inhabiting regions far from the equator are at risk of Vitamin D deficiency due to limited sun exposure.
Iron deficiency is a common nutritional disorder in many developing nations where it affects mainly women and children. Iron binds with hemoglobin and subsequently transports oxygen to cells. Iron is divided into two dietary categories. Heme iron is the more easily-absorbed of the two types, and it is present in animal products while the non-heme iron is obtained from both plant and animal foods, but it is not as well-absorbed. Vegetarians stand a higher risk of iron-deficiency since they eat only non-heme iron. Iron deficiency mainly manifests as anemia whose symptoms include impaired brain function, weakness, and a weakened immune function. Red meat, organ meat, beans, broccoli, seeds, and canned sardines are good sources of iron.
2. Vitamin A
Vitamin A consists of several fat-soluble retinoids such as retinal and retinol. The element is critical in vision, immune function, reproduction, and formation and maintenance of healthy bones, teeth, cell membranes, and skin. There are two groups of dietary Vitamin A. Preformed Vitamin A is obtained from animal products such as dairy, fish, and meat while Pro-Vitamin A is acquired from plant-based products mainly fruits and vegetables. Vitamin A deficiency is mostly reported in developing nations where it causes temporary and permanent blindness and suppressed immunity.
Iodine is necessary for the production of thyroid hormone like thyroxine and the proper functioning of the thyroid gland. Thyroid hormones aid the body to regulate metabolic rate, stimulate brain development, and overall growth among other processes. Iodine deficiency affects about one-third of the world's population. The deficiency commonly manifests as goiter, which is the swelling of the thyroid gland, shortness of breath as well as increased heart rate. The symptoms of iodine deficiency in children include developmental abnormalities and mental retardation. Iodine deficiency is a major concern in developing countries in Africa, the western Pacific, and South-East Asia. Australia and New Zealand also report significant cases of the condition. Iodine can be obtained from seaweed, dairy, fish, and eggs. The addition of iodine to salt has also helped several countries curb the deficiency.