Last Updated on 15th March 2019
Dr Noureen Ahmad
General Practitioner, Belgium
In terms of nutrition, minerals are chemical elements that are part of essential nutrients for the body. There are various minerals, but the most important and common mineral deficiencies will be discussed in this article. These include calcium, magnesium, iron, zinc and iodine. Other mineral deficiencies such as copper, chromium, selenium, manganese and fluoride are quite uncommon.
In resource-rich countries, most foods are fortified with these minerals, so deficiencies of these occur in undeveloped countries like Asia and Africa.
The first mineral to be discussed is calcium, which is an essential nutrient that is mostly (98%) present in the bones of our body. Calcium uptake is regulated and coordinated by vitamin D and plays a big role in muscle contraction, nerve conduction and skeleton rigidity. Good sources of calcium are to be found in dairy products (milk, cheese, yoghurt) and vegetables (okra, spinach, soybeans).
There are two medical conditions known for calcium: hypocalcemia (low calcium level in the blood) and hypercalcemia (high calcium level in the blood). Hypocalcemia occurs in people with chronic kidney diseases, vitamin D deficiency and magnesium deficiency. The low calcium in the body can result in muscles cramps, irritability, anxiousness, skin lesions, impaired orientation and confusion. In cases of severe low levels, it can lead to seizures and heart problems. Treatment includes giving calcium supplementation depending on the calcium level, which is determined from blood samples.
Hypercalcaemia occurs mostly in people who suffer from a malignancy (bone related cancers), thus individuals with high levels should be checked thoroughly for this. Hypercalcemia can result in abdominal pain with vomiting, hard stools, weight loss, tiredness, confusion, high blood pressure and kidney stones. Treatment for this condition would include hydration and treating the underlying cause.
The second mineral is magnesium, of which 65% is distributed in the bones and 35% in the cells. Good sources of magnesium are present in many different foods like whole wheat, spinach, quinoa, nuts, black beans, avocado and yoghurt. Due to the good distribution of magnesium in many foods, deficiency of this mineral is uncommon. In specific situations, such as severe diarrhoea and alcohol abuse, magnesium deficiency can occur and can lead to seizures and heart rhythm problems. Treatment for this deficiency would be to take magnesium supplements.
Iron deficiency is really common and affects many people around the world. Most of the iron (75%) is incorporated as haemoglobin (Hb), a protein that is important for the transport of oxygen to cells. The other part of iron is available in myoglobin form, a protein that stores oxygen in the muscles. The remaining part of the iron in the body is stored as ferritin in the liver.
Good sources of iron are found in two forms: haem form (meat, fish and poultry) and non-haem form (many vegetables and fruits). However, the haem form of iron is better absorbed. In some countries, iron is fortified in bread and cereals to prevent this medical problem. Iron deficiency can lead to microcytic anaemia, meaning a lack of adequate red blood cells. This is known as the most common form of anaemia in the UK. Causes of this can be due to blood loss in the gastro-intestinal system or from the gynaecological system or malabsorption.
The symptoms of this deficiency include fatigue, irritability, concentrating problems, weakness, dry skin and multiple lesions in the mouth. In severe anaemia, it can even lead to chest pain and shortness of breath. The iron status in the body can be derived from the blood tests such as serum ferritin and TIBC (total iron binding capacity) as well as other blood tests.
Treatment exists in first treating the underlying cause of iron deficiency and when this is known, iron supplementation can be started as therapy. The guidelines recommend starting with 100-200 milligrams of iron (ferrous sulphate or fumarate). However, these tablets can cause abdominal discomfort, nausea, hard and black stools, so it is recommended to start with a low dose. Taking iron with vitamin C (orange juice) increases the iron absorption and is sometimes medically advised. If iron tablets are impossible to endure due to side effects, supplementation can be given by intravenous (through veins) or intramuscular (through injections in muscles). While giving iron supplementation, it is important to check the Hb concentration regularly in the blood. The iron supplementation should be continued till Hb is normal for at least 3 months to replenish stores.
The next mineral is zinc. Deficiency of zinc is uncommon and occurs in individuals with tube feeding or from a poor diet. Low zinc in the body can result in hair loss, multiple skin lesions near the nose and mouth, night blindness, diarrhoea and can be a cause of complaints of the male reproductive system. Blood levels of zinc are unreliable as it can be influenced by many factors, so it is recommended to start with a trial of zinc supplementation and evaluate the clinical presentation afterwards.
The last mineral to discuss is iodine. This mineral plays an essential role in the synthesis of the thyroid hormones. Low iodine can result in less production of these thyroid hormones, which are required for regulation of basal metabolic rate and can eventually lead to a goiter (thyroid enlargement) and hypothyroidism (less working thyroid). However, iodine is present in many foods like fish, seafood and vegetables but also in drinking water. In most countries, salt is fortified with iodine, so deficiency of this mineral is uncommon.
(Always discuss with your doctor what supplements you want to take or are taking so your health and wellbeing can be properly looked after.)