Despite its name, vitamin D is not a vitamin, but a prohormone, or precursor of a hormone. Vitamin D promotes calcium absorption in the gut and maintains adequate serum calcium and phosphate concentrations to enable normal bone mineralisation and to prevent hypercalcaemic tetany (involuntary contraction of muscles, leading to cramps and spasms), the National Institutes of Health Office of Dietary Supplements (NIH-ODS) advised. “It is also needed for bone growth and bone remodelling by osteoblasts and osteoclasts. Without sufficient vitamin D, bones can become thin, brittle, or misshapen. Vitamin D sufficiency prevents rickets in children and osteomalacia in adults. Together with calcium, vitamin D also helps protect older adults from osteoporosis.
According to NIH-ODS, vitamin D also has other roles in the body, including reduction of inflammation as well as modulation of such processes as cell growth, neuromuscular and immune function, and glucose metabolism. “Many genes encoding proteins that regulate cell proliferation, differentiation, and apoptosis are modulated in part by vitamin D.”
Magnesium plays an important role in assisting more than 300 enzymes to carry out various chemical reactions in the body. These include building proteins and strong bones, and regulating blood sugar, blood pressure, and muscle and nerve functions. According to the Harvard School of Public Health (HSPH), magnesium also acts as an electrical conductor that contracts muscles and makes the heartbeat steadily. “Getting enough magnesium can help prevent or treat chronic diseases, including Alzheimer’s disease, type 2 diabetes, cardiovascular disease, and migraine,” registered dietitian nutritionist, Megan Ware, reported for Medical News Today.
A true deficiency occurs with a long-term low magnesium diet, malabsorption, and large losses from alcohol abuse or use of medications that deplete magnesium (some diuretics, proton pump inhibitors, and antibiotics). NIH-ODS cautioned that early signs of magnesium deficiency include loss of appetite, nausea, vomiting, fatigue, and weakness. “As magnesium deficiency worsens, numbness, tingling, muscle contractions and cramps, seizures, personality changes, abnormal heart rhythms, and coronary spasms can occur. Severe magnesium deficiency can result in hypocalcaemia or hypokalaemia (low serum calcium or potassium levels, respectively) because mineral homeostasis is disrupted.”
Calcium is the most abundant mineral in the body, and it is vital for bone health. “Calcium makes up much of the structure of bones and teeth and allows normal bodily movement by keeping tissue rigid, strong, and flexible,” said NIH-ODS. “The small, ionised pool of calcium in the circulatory system, extracellular fluid, and various tissues mediates blood vessel contraction and dilation, muscle function, blood clotting, nerve transmission, and hormonal secretion.” Evidence suggests calcium might play a role in bone health in older adults, cancer, cardiovascular disease (CVD), preeclampsia, weight management, and metabolic syndrome.
Calcium deficiencies can affect all parts of the body, resulting in weak nails, slower hair growth, and fragile, thin skin. Hypocalcaemia, or calcium deficiency disease, occurs when the blood has low levels of calcium. This is usually a result of “diseases such as kidney failure, surgeries of the digestive tract like gastric bypass, or medications like diuretics that interfere with absorption,” HSPH explained. Complications from calcium deficiency disease include eye damage, an abnormal heartbeat, and osteoporosis.
An essential mineral, zinc is involved in numerous aspects of cellular metabolism. The NIH-ODS advised that “it is required for the catalytic activity of approximately 100 enzymes, and it plays a role in immune function, protein synthesis, wound healing, DNA synthesis, and cell division. Zinc also supports normal growth and development during pregnancy, childhood, and adolescence, and is required for proper sense of taste and smell. A daily intake of zinc is required to maintain a steady-state because the body has no specialized zinc storage system.”
Because excess zinc can interfere with the absorption of iron and copper, and high doses of zinc can cause nausea and even vomiting, HSPH warned that supplemental zinc should not be taken by patients unless it is known that the diet is low in foods containing zinc or a zinc deficiency is confirmed.
According to Prof Steven Abrams (Professor, Department of Paediatrics at Dell Medical School at the University of Texas at Austin, and UpToDate.com author), zinc deficiency is an important component of nutritionally related morbidity worldwide. “Symptoms attributable to severe zinc depletion include growth failure, primary hypogonadism, skin disease, impaired taste and smell, and impaired immunity and resistance to infection.” Fortunately, zinc supplementation in populations at risk for zinc deficiency appears to have beneficial effects on the incidence and outcome of serious childhood infectious diseases,” Prof Abrams advised.
Iron is a mineral vital to the proper function of haemoglobin, a protein needed to transport oxygen in the blood, Ware advised. “Iron helps to preserve many vital functions in the body, including general energy and focus, gastrointestinal processes, the immune system, and the regulation of body temperature.” As a component of myoglobin, another protein that provides oxygen, NIH-ODS explained that iron supports muscle metabolism and healthy connective tissue and is also necessary for physical growth, neurological development, cellular functioning, and synthesis of some hormones. Furthermore iron promotes a healthy pregnancy as expectant mothers face an increased demand for new red blood cells to supply the growing foetus with oxygen and nutrients. In fact, according to a study by HSPH, taking even a small amount of iron during pregnancy cuts a woman’s risk of developing anaemia and decreases the risk that her baby will be born with low birth weight.
Affecting 3-5 billion people, iron deficiency is one of the most common nutritional disorders in the world. A shortage of iron in the blood can lead to a range of serious health problems, including iron deficiency anaemia. “Challenges in the treatment of iron deficiency include finding and addressing the underlying cause and the selection of an iron replacement product that meets the needs of the patient,” reported Dr Jacquelyn Powers (Assistant Professor of Paediatrics at Baylor College of Medicine, and UpToDate.com author).