Minerals: where to get them and how to take them

Nutrition articles often talk about vitamins and minerals as crucial components of a healthy diet. While the importance of vitamins is well understood, minerals can be more confusing. It’s unclear whether they’re necessary, if we get enough from our daily food intake, or if supplements are needed. To clear up these questions, I investigated the need for mineral supplements and their effectiveness, leading to a discovery that the sales of zinc supplements increased by 370.3% this year.

This article will provide an overview of the following minerals:

• Calcium
• Phosphorus
• Magnesium
• Potassium
• Sodium and chlorine
• Chromium
• Copper
• Fluoride
• Iodine
• Iron
• Manganese
• Molybdenum
• Selenium
• Zinc

What minerals are and why they are important

What are Minerals?

The human body is made up of 29 chemical elements, but not all are essential. The four main elements, carbon, hydrogen, oxygen, and nitrogen, make up 96% of our body weight and are the fundamental components of all proteins, fats, and carbohydrates. These elements are essential for our survival, but some other elements in our bodies are still not well understood for their health significance. Cadmium, nickel, silicon, tin, vanadium, and aluminum might play important roles, while others like gold, mercury, cyanide, and lead are not useful.

Basic minerals are the inorganic substances that make up about 2% of our body weight and are vital for transforming proteins, fats, and carbohydrates into living matter. These minerals are divided into two categories: macronutrients and micronutrients.

Macronutrients: A healthy diet must include more than 100 mg per day of each of the following macronutrients: calcium, chlorine, magnesium, phosphorus, potassium, and sodium. These substances are essential to the concentration levels in our organs and systems such as bones, muscles, heart, and brain.

Micronutrients: Our daily diet requires less than 100 mg of the following micronutrients: chromium, copper, fluorine, iodine, iron, manganese, molybdenum, selenium, and zinc. These micronutrients are found in enzymes, which control vital biochemical reactions. For example, iron contributes to the hemoglobin enzyme that carries oxygen to cells and removes carbon dioxide from them.

Biochemical reactions in the body may go wrong or stop if a person is not getting enough minerals from their diet, due to malnutrition, a monotonous diet, or health problems that prevent mineral absorption.

Different people have different mineral needs based on their sex, age, and health conditions. Government guidelines for daily mineral intake vary by country, but generally follow WHO guidelines. Minerals, like vitamins, only treat deficiencies that cause associated diseases. Iodine supplements, for example, can help those with thyroid problems due to iodine deficiency. However, supplements can’t cure other diseases or enhance physical and mental abilities in healthy people.

Calcium

Macronutrients are present in the body in two forms: solid and free.

99% of all minerals in the body are mineralized calcium. It is the building block of bones and teeth. The remaining 1% is calcium-free. Free calcium helps muscles contract, hormones flow, nerve impulses are transmitted in neurons, and certain proteins, such as blood clotting factors, are activated.

The products that contain. Calcium is found in many foods, such as milk, hard cheese, cottage cheese, yogurt, and green veggies such as cabbage and broccoli.

Macronutrients exist in two forms in the body: solid and free. 99% of all minerals in the body are mineralized calcium, which is the building block of bones and teeth. The remaining 1% of calcium-free minerals help regulate muscle contraction, hormone flow, nerve impulses, and activation of certain proteins like blood clotting factors. Calcium is abundant in foods such as milk, cheese, yogurt, and green vegetables like cabbage and broccoli.

Daily Requirements: The recommended daily dose for adults is 1000 mg, for people over 60 years old it’s 1200 mg, and for children it ranges from 400-1200 mg.

Symptoms of Deficiency: Healthy individuals who have a balanced diet usually do not have a calcium deficiency. The human body efficiently manages calcium, using only the amount necessary for functions and storing the excess in bones or excreting it through urine.

However, individuals with an increased calcium requirement, such as pregnant women and breastfeeding mothers, may develop a deficiency. This is often seen in people with calcium metabolism issues, such as excretion of too much calcium through the kidneys due to illness or patients with hypoparathyroidism, where the parathyroid glands do not produce enough hormone to regulate calcium levels in the body.

In most cases, low calcium levels in the blood do not cause any symptoms. However, if calcium is unavailable for an extended period, hypocalcemia may develop, causing dry and flaky skin, brittle nails and hair, back or leg cramps, and minor skin hemorrhages.

Low calcium levels in the body can result in depression, memory loss, and hallucinations. Some symptoms of severe calcium deficiency include tingling in the tongue, lips, fingers, and feet, muscle pain, cramps in the throat, and irregular heartbeats.

Excess calcium symptoms can manifest in various ways. Since calcium is excreted in urine, healthy individuals will not suffer from an overdose even if they excessively use calcium supplements, which are also ineffective. Only individuals taking high amounts of vitamin D – which aids calcium absorption – and those with conditions that affect calcium metabolism will have elevated calcium levels in their blood. For instance, hyperparathyroidism or Paget’s disease can cause an increase in blood calcium levels as bones are broken down. Supplements are not typically prescribed for healthy adults, as they receive enough calcium through their diet. However, people at risk of calcium deficiency may be given 500 mg of calcium in supplements, which are best absorbed at this dose. Pregnant, lactating, or elderly women are at a high risk of developing osteoporosis, a condition that results in rapid calcium loss from bones.

For those with serious illnesses causing calcium deficiency or excess, intravenous drugs or high-concentration supplements may be prescribed. Dosage is determined on a case-by-case basis and in some instances, vitamin D supplements may be given alongside calcium supplements to enhance absorption.

When to test? A test may be ordered for serious diseases causing calcium deficiency or excess, including urolithiasis, bone diseases, hypertension, gout, myopathy, stomach ulcers, and pancreatitis, among others.

Normal Range. Normal blood calcium levels range from 2.15 – 2.5 mmol/l.

Combining calcium with vitamin D is an option. Magnesium supplements and medications can decrease calcium absorption and should not be taken at the same time as calcium. Food is the best source of calcium. Calcium supplements are most effectively absorbed when taken with food and in combination with vitamin D supplements.”

Phosphorus

This is a macroelement, with about 85% of it found in hydroxyapatite crystals primarily in bones and teeth, and the remaining found in compounds used for energy, cell membranes, DNA, and RNA. Products containing phosphorus include meat and poultry, dairy products, fish, eggs, nuts, legumes, vegetables, and grains. It is easier to absorb phosphorus from animal sources.

Daily Allowance Recommendations. Adults should aim for 800 mg of phosphorus daily, while children’s requirements range from 300 to 1200 mg.

Deficiency Symptoms. Healthy individuals who have a balanced diet are unlikely to experience phosphorus deficiency. However, those with hypothyroidism, alcoholism, severe burns, or rare genetic diseases may have low levels of phosphorus in their blood. Severe deficiency can lead to muscle weakness, osteomalacia, anemia, and even seizures.

Excess Symptoms. The effects of excess phosphorus (above 1000 mg per day) are controversial. While some studies suggest a link to heart, kidney, and bone diseases, others do not support this. On the other hand, taking 6600 mg of sodium phosphate twice a day can lead to poisoning and calcification in the soft tissues, particularly the kidneys. Most cases of high phosphate levels are due to kidney failure to eliminate excess phosphorus caused by diseases or injuries.

Medical Uses of Supplements. Phosphorus supplements are prescribed for those with medical conditions leading to phosphorus deficiency. Dosage is determined by a doctor.

Testing Recommendations. Testing for phosphorus levels should be done when managing a condition that causes deficiency, such as severe burns or alcoholism.

Blood phosphorus levels vary with age, but a healthy adult’s concentration should fall between 0.87-1.45 mmol/l. Phosphorus can be better absorbed with vitamin D. Avoid Combining with calcium from supplements can interfere with phosphorus digestion, so it is best to take them separately. The best way to get adequate phosphorus is through food, as it is easily absorbed by the body. Healthy individuals do not typically require supplements.

Magnesium

Approximately 25 g of magnesium can be found in the human body, with over half stored in the bones and the rest in soft tissues. Magnesium is crucial for transmitting nerve impulses and participating in 300 biochemistry reactions such as energy production, protein synthesis, DNA synthesis, and blood sugar regulation.

Sources of magnesium include various foods, particularly dark green leafy vegetables, bananas, dried apricots, avocados, nuts, beans, legumes, whole grains, and milk.

Daily recommended intake of magnesium is 400 mg for adults and 55-400 mg for children. In healthy people who eat a normal diet, magnesium deficiency is rare as the mineral is found in many foods. The kidneys will excrete less magnesium if there is not enough in the diet, but this only works to a certain point. People with alcohol addiction and those whose intestines and kidneys excrete too much magnesium are more likely to have a magnesium deficiency.

A decrease in magnesium concentration in the blood does not cause symptoms, but severely low magnesium levels can cause nausea, vomiting, drowsiness, weakness, and muscle cramps. The body is able to regulate the amount of magnesium consumed, and if there is too much, the kidneys will excrete it along with urine. Therefore, magnesium levels only rise in people who take supplements or medication containing magnesium.

In the case of a severe overdose, muscle weakness, low blood pressure, impaired breathing, and a potential heart stoppage can occur. Magnesium supplements and medications are usually prescribed for people suffering from alcoholism, for those who have lost a lot of fluids, and for patients suffering from diseases in which the body excretes too much magnesium in the urine. Blood tests for magnesium levels are recommended only for patients taking magnesium-containing medications to avoid poisoning.

Because vitamin D improves the absorption of magnesium from food, they are often given together to patients. However, supplementing with high doses of zinc, more than 142 mg, interferes with the absorption of magnesium and is not recommended. Food sources such as nuts, fruits, or milk are better sources of the mineral as they provide optimal concentrations of the mineral and are absorbed gradually without the risk of harm to health.

Potassium

Potassium is an essential macronutrient that plays a crucial role in the functioning of all cells in the body. It helps to recharge cell membranes and enables nerves to transmit electrical signals and muscles to contract. Maintaining the proper level of potassium in the blood is critical for heart health, as disruptions to potassium levels can lead to heart dysfunction.

When it comes to sources of potassium, there are many foods that are high in this important mineral. These include meat, chicken, fish, broccoli, peas, beans, and tomatoes.

The daily recommended allowance of potassium for adults is 2500 mg, while for children it ranges from 400-2500 mg. Potassium levels in the blood are regulated by the kidneys, so healthy people generally don’t have a deficiency and don’t need supplements. A deficiency can occur due to high urine potassium levels, excessive loss from the gastrointestinal tract, or excessive removal from cells, which can be seen in conditions such as thyrotoxicosis.

If potassium levels drop below 3 mmol/L, muscle weakness can occur and serious conditions such as paralysis, respiratory failure, spasms, and intestinal obstructions may result. Excess potassium in the blood is not common in healthy people and is usually caused by an underlying illness or medication. A slight increase in potassium concentration doesn’t cause symptoms, but a high level can lead to life-threatening arrhythmias.

Potassium supplements and medications are only prescribed to patients who experience significant potassium loss due to an underlying illness or medication. The amount of potassium in a medication must be individually selected by a physician. A potassium level test is usually prescribed to patients in the hospital and on potassium medications to prevent overdose. A normal potassium level in the blood is between 3.5-5 mmol/L. Potassium is best obtained through food and healthy people don’t require supplements.

Sodium and chlorine

The functioning of all cells in the body depends on sodium. Sodium, similar to potassium, helps in recharging the cell membrane but it is present outside rather than inside. Sodium plays a crucial role in enabling nerves, muscles and all organs and tissues in our body to work. The body uses chlorine to regulate fluid balance and produce gastric juice.

Sources of these elements are abundant and can be found everywhere, including drinking water. The majority of sodium and chlorine can be found in processed and canned foods, as table salt, which consists of 40% sodium and 60% chloride, is added to these products.

The recommended daily intake of sodium and chlorine is 1300mg for adults and 200-1300mg for children. The kidneys regulate the levels of these minerals in the blood by retaining them if there is a deficiency in the diet and excreting them if there is a surplus. However, there are situations where even a healthy individual can lose too much of these minerals, such as excessive sweating or vomiting. People with certain diseases, such as kidney inflammation or liver cirrhosis, or taking certain medications can also experience a decrease in blood sodium levels.

A lack of sodium in the blood can lead to a number of symptoms, with the brain being the most sensitive. The first symptoms are lethargy and confusion, followed by muscle cramps and eventually, if not treated, a coma. Excess levels of sodium and chlorine in the blood can also occur due to overconsumption of salt in food, dehydration, or other health conditions such as hypothyroidism and uncompensated type 2 diabetes. This can result in increased blood pressure, intense thirst, and potentially, seizures, a coma, or death.

For people who have lost a lot of sodium through their body fluids, saline tablets or rehydration solutions are typically prescribed. A sodium and chlorine test is recommended for those with diseases associated with changes in mineral levels in the blood. A normal blood level is considered to be 135-145 mmol/l.

In order to maintain healthy levels of sodium and chlorine, it is recommended to eat fresh food, limit the use of salty sauces, and undersalt foods if possible. This can help reduce hypertension and other cardiovascular diseases, leading to overall better health. Medical organizations generally believe that we are getting too much salt, so reducing salt intake is crucial for maintaining good health.

Chromium

Chromium is a component of an enzyme that accelerates insulin’s action, which moves glucose from blood to cells. The impact of chromium on insulin is established, but the exact mechanism is not yet understood by scientists.

Brewer’s yeast has the highest amount of chromium, but it is not a common source. Chromium can be easily obtained from sources like meat, whole grains, liver, eggs, broccoli, onions, and tomatoes. Processed meats like sausages contain more chromium compared to unprocessed meat.

The recommended daily amount for adults is 50 mcg and for children is 11-35 mcg. A balanced diet is usually sufficient to prevent chromium deficiency in healthy individuals. However, it is more common in individuals suffering from serious illnesses such as extensive burns, trauma, short bowel syndrome, and severe diabetes. Symptoms of chromium deficiency include rapid weight loss, impaired coordination, and difficulties with spatial orientation.

Excessive intake of chromium is not a concern as it is not easily absorbed and is largely excreted in feces. However, it may pose a threat to individuals with kidney disease.

Chromium deficiencies associated with intravenous nutrition can be treated with medications containing 10-15 mcg of chromium. The benefits of chromium supplements for patients with type 2 diabetes are still being debated by researchers. As a general rule, it is advisable to consult with a doctor before taking chromium supplements. Chromium levels in the blood cannot be measured with standard tests.

Vitamins C and B3 can improve the absorption of chromium from the intestine. Iron and zinc, on the other hand, interfere with chromium absorption, so it is best to avoid taking them together. Supplement manufacturers recommend taking chromium picolinate to lose weight and increase muscle strength, however, there is no scientific evidence supporting these claims. To maximize absorption, it is best to take chromium with a meal.

Copper

Copper is an essential mineral that plays a critical role in the body. It is involved in several enzymatic processes, such as forming connective tissue, bones, and assisting in the metabolism of iron. Additionally, it is also important for blood clotting.

If you’re looking to incorporate more copper into your diet, there are several food sources that are rich in this mineral. Some of these include oysters, whole grains, legumes, nuts, potatoes, kidneys, and liver.

Recommended Dosage: Adults should consume 1 mg daily, while children should take 0.5-1.0 mg.

Deficiency Symptoms: Copper deficiency is uncommon in healthy adults due to ceruloplasmin protein storing copper in the body. Deficiency mainly occurs in newborn boys with Menkes syndrome, a genetic disorder that hinders proper copper absorption. Copper deficiency in adults is usually due to malabsorption issues such as Crohn’s or cystic fibrosis. Lack of copper leads to weakness, fatigue, depression, irritability, tingling, coordination loss, anemia, high cholesterol, connective tissue and osteoporosis disorders.

Excess Symptoms: In healthy individuals without metabolic problems, excess copper is eliminated from the body. Copper poisoning is rare and caused by drinking water from copper-containing pipes. Only people with Wilson disease, a hereditary disorder in which copper is not excreted properly and accumulates in tissues, are at risk of copper poisoning from food/supplements. Wilson disease patients face neurological disorders and liver damage that could result in hepatitis or cirrhosis.

Copper supplements or injections are only recommended for illnesses that result in copper deficiency, and the appropriate dosage is determined by a physician.

Normal copper blood levels are between 85-180 micrograms per deciliter (mcg/dL). In certain countries, copper content is determined through examination of ceruloplasmin, a protein that stores copper, with normal levels ranging from 180-450 mg/L. Zinc hinders copper absorption, therefore, these supplements should not be taken simultaneously.

Fluoride

Fluoride: A macronutrient for Strong Bones and Teeth.

Sources of Fluoride: The main source of fluoride is tap water. Seafood is also a rich source of fluoride due to its high fluoride compounds found in seawater. Tea also contains fluoride.

Recommended Daily Intake: The recommended dose for adults is 4 mg and for children, 1.0-4.0 mg.

Symptoms of Deficiency and Excess: In areas with a fluoride content of 0.7-1.2 mg/l in drinking water, deficiencies are unlikely to occur. But if the fluoride content is low, it can lead to tooth decay or osteoporosis. On the other hand, excessive fluoride intake can cause fluorosis, which results in white spots on the teeth.

Fluoride toothpaste and mouthwash are recommended for those who drink water low in fluoride. Some children may require supplements, but a doctor’s prescription is necessary to adjust the dose. There is limited evidence that fluoride supplements improve bone health.

Testing for fluoride levels is rare and typically not necessary.

The best way to consume fluoride is through tap water. Using fluoridated toothpaste or mouthwash is recommended for those with low fluoride content in water. A toothpaste with 1350 ppm fluoride is sufficient and rinses are not needed. In the case of excessive fluoride in water, avoiding fluoridated toothpaste and rinse aids can help prevent fluorosis.

Iodine

Iodine is a trace element crucial for the creation of thyroxine (T4) and triiodothyronine (T3) hormones that regulate metabolism, body temperature, appetite and metabolism. It can be found in fish such as cod, sea bass, and haddock, in algae, dairy products and fortified foods like iodized salt.

An adult’s recommended intake is 150 mcg, while children’s is between 60-150 mcg.

Signs of Deficiency: Iodine shortage is prevalent in individuals residing in areas away from the ocean. The deficiency is rarely obvious through appearance or health. A prolonged lack of iodine can result in goiter, a swelling in the neck due to an enlarged thyroid gland as the body tries to acquire more of the element from food.

Insufficient iodine levels can lead to an inactive thyroid gland and result in symptoms such as swelling, weight gain, decreased performance, hoarse voice, dry and flaky skin, and thin, coarse hair.

Pregnant women are at a higher risk of iodine deficiency, which can inhibit the development of the fetus. To prevent this, the thyroid gland is checked during the first trimester.

While the thyroid gland can regulate the amount of iodine received from food in healthy individuals, excessive intake of iodine through supplements or medications can lead to poisoning. This can result in either hyperthyroidism or hypothyroidism, both of which can cause the gradual development of a goiter. In the case of hyperthyroidism, additional symptoms such as rapid heartbeat, trembling hands, excessive sweating, nervousness, and sleep disturbances may occur.

Hypothyroidism caused by iodine deficiency can be treated with supplements or drugs, but it’s crucial that the doctor selects the right level of iodine as too much can also be harmful.

Iodine levels cannot be evaluated through blood tests, but a urine test for iodine can be performed to monitor the treatment of thyroid disorders. Normal urine content ranges from 100-500 mcg/l.

Seafood is the best source of iodine for individuals without thyroid problems, while iodized salt can be a suitable alternative for those living far from the sea. Taking iodine supplements without a prescription can be dangerous and can result in hyperthyroidism.

Iron

Iron, a trace element, is an essential component of enzymes that regulate respiration, energy production, and DNA synthesis. It plays a crucial role in the formation of red blood cells – erythrocytes.

Food sources. Iron can be found in various foods such as liver, beef, dark meat poultry, oysters, salmon, tuna, beans, dried fruit, and whole grains. Although iron from plant-based foods is not easily absorbed, its absorption is increased by three times when combined with animal-based foods.

Adult males require 10 mg of iron daily, while adult females need 18 mg, and children require 4-18 mg.

Iron deficiency is common in women, especially pregnant women, young children, and strict vegans. Menstruating women can experience significant iron loss and have trouble replenishing their iron stores through food. In pregnancy, iron is used to form the fetus, while in childhood, it is necessary for growth. Adults may lose iron due to bleeding or bowel diseases that interfere with nutrient absorption, such as celiac disease. If iron stores are severely depleted, iron deficiency anemia can occur, causing symptoms like paleness, weakness, difficulty paying attention, and reduced ability to learn.

On the other hand, a healthy person cannot be poisoned by iron from food or supplements. However, in individuals with hereditary hemochromatosis, who are unable to handle excess iron, iron can deposit in soft tissues and lead to heart disease, diabetes, arthritis, cirrhosis, and an increased risk of liver cancer.

Iron deficiency anemia is treated with iron supplements, and it is up to the physician to select the best medications and supplements. The best way to measure iron levels in the blood is to measure ferritin levels, the protein in which iron is stored. Blood ferritin levels should be within the range of 20-250 mcg/l for men and 10-120 mcg/l for women. Vitamin C can enhance iron absorption, so it is recommended to consume iron-rich animal products with vegetables and fruit. However, taking iron and manganese together is not recommended as it impairs manganese absorption. Healthy adults should be able to get enough iron from food and do not need additional iron supplements. Those with iron deficiency anemia should follow the dosage prescribed by their doctor.

Manganese

Manganese is an important trace element that plays a key role in various metabolic processes within the body. It is a component of enzymes responsible for glucose production, protein synthesis, and protection of mitochondria, the energy centers of cells, from oxidation.

The mineral can be easily obtained through a balanced diet that includes a variety of food sources. Good sources of manganese include nuts, legumes, seeds, whole grains, green leafy vegetables, shellfish, meat, fish, and poultry. Tea is a rich source of manganese, but its absorption by the body is limited.

The recommended daily intake for adults is 2 mg, while the recommended dose for children has yet to be established.

Deficiency of manganese is rare, occurring only in individuals with a very limited diet. Its symptoms include slowed growth and weakened bones in children, skin rashes and premature graying in men, and premenstrual pain in women. Despite the widespread occurrence of manganese in food items such as nuts, legumes, whole grains, vegetables, shellfish, and meats, manganese poisoning is still unknown. However, manganese dust can be toxic, as seen in miners and welders, and excess manganese can be eliminated from the body through bile excretion. People with chronic liver disease, who have impaired bile production, may accumulate manganese in their tissues, leading to coordination disorders, headaches, and vomiting.

There are currently no reliable tests to diagnose manganese deficiency, and there is limited evidence supporting the effectiveness of manganese supplementation for any medical conditions. The concentration of manganese in the blood is not usually measured in clinical practice, but its normal range is believed to be 4-15 mg/L. It is important to note that iron foods and supplements can reduce the intestinal absorption of manganese, while zinc may increase it.

Manganese supplementation has not yet been proven to be beneficial, and the best way to obtain this mineral is through food.

Molybdenum

As a trace element, it participates in enzymes responsible for protein synthesis/breakdown, urea formation, and DNA disposal. Foods that contain it: nuts, legumes, whole grains, beef liver.

Daily recommended requirement for molybdenum is 70 mcg for adults. There are no established norms for children.

A deficiency in molybdenum is extremely rare, with only one recorded case in a person with severe Crohn’s disease who was receiving intravenous nutrition. The symptoms of deficiency include rapid breathing, headaches, night blindness, and a coma. Once molybdenum was added to the patient’s nutrient solution, they regained consciousness.

Molybdenum deficiency can also occur as a result of very rare genetic disorders, but these cases usually result in the death of the affected individual shortly after birth.

There have been very few recorded cases of molybdenum poisoning from food, with the most notable case being residents of one Armenian village who consumed excessive amounts (10-15 mg per day) leading to a disease similar to gout.

Molybdenum supplements are mainly prescribed to individuals with genetic disorders and are added to fluids given to IV fed patients. A mineral test for molybdenum is very rarely needed as a deficiency is so rare that there is no established blood level for a healthy individual.

The best way to ensure proper absorption of molybdenum is through a balanced diet that includes foods such as legumes, grains, and leafy vegetables.

Selenium

Selenium is an essential trace element required by enzymes in the human body to protect cell membranes from damage and to facilitate thyroid hormone synthesis. It can be found in veggies and fruits, fish and shellfish, red meat, grains, eggs, chicken, liver, and garlic.

Daily recommended intake: Women: 55 mcg; Men: 70 mcg; Children: 10-50 mcg. Deficiency is rare in well-nourished individuals; mostly affects those living in areas with scarce selenium soil, causing Keshan and Kashin-Beck diseases.

The Coxsackie virus can cause heart muscle damage in individuals with Keshan disease, a potentially fatal condition. On the other hand, those with Kasin-Beck disease face joint deformities and dwarfism due to the destruction of articular cartilage.

People undergoing hemodialysis and those with cystic fibrosis are at risk of selenium deficiency. Excessive selenium intake can lead to toxicity, causing symptoms like metallic taste in the mouth, nausea, vomiting, and diarrhea. Continuous consumption of high selenium foods can result in hair loss, nail breakage, skin rashes, and tooth discoloration. Note that selenium toxicity can occur not only from supplements but also from eating Brazil nuts grown in selenium-rich soil. Hence, moderation is key if you enjoy eating these nuts.

Supplements are often used to treat Keshan and Kasin-Beck diseases and sometimes cystic fibrosis. However, the concentration of selenium should be carefully selected by a doctor as it can be toxic in large doses.

Regular monitoring of selenium levels in the blood is important, and the normal level is 8 mg/dL. Taking selenium supplements without a medical indication is not recommended and can be harmful to health. It is best to obtain selenium through a balanced diet and regular products for optimal absorption.

Zinc

“Zinc, a trace element, plays a crucial role in the functioning of over 100 enzymes, including those involved in immunity, protein synthesis, and wound healing. Good dietary sources of zinc include beef, pork, lamb, and dark poultry. However, zinc intake from fruits and vegetables is often low.

Adults should take 12 mg of zinc, while children should take 3-12 mg. Zinc deficiency is rare in individuals consuming a normal diet, including vegetables and meat. However, strict vegans may experience it. Deficiency occurs in people with poor zinc absorption or rapid excretion, such as those with diabetes, liver or kidney disease, or on diuretic therapy. Symptoms include hair loss, frequent colds, dermatitis, and slow wound healing.

Acute or chronic zinc poisoning can occur with symptoms of nausea, vomiting, abdominal cramps, diarrhea, and headaches in acute poisoning. Chronic poisoning may result from daily consumption of 150-450 mg of zinc supplements and may cause frequent illness, low blood iron levels, and possible diseases of the genitourinary system.

Zinc supplements are prescribed when deficiency is confirmed, at a dosage of 15-120 mg per day, to be selected by the doctor. There is insufficient evidence that zinc helps with colds or COVID-19, despite being studied since 1984. Diagnosing zinc levels is difficult through blood tests and is usually based on clinical manifestations such as symptoms and appearance. Zinc supplements should be taken with caution and with a doctor’s prescription. The best source of zinc is food.

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