Essential minerals are inorganic compounds that help the body function properly. They are involved in everything from the composition of bones, blood and teeth to muscle function. There are seven macrominerals that the body requires in large amounts; they are calcium, chloride, magnesium, potassium, sodium, sulfur and phosphorous. There are also several minerals needed in smaller amounts, called trace minerals. Trace minerals include chromium, copper, fluoride, iodine, iron, manganese, molybdenum, selenium and zinc. This article will cover the minerals, how they are obtained and their role in the body.
Calcium is the most abundant mineral in the body. It is found in some foods, added to others, available in supplement form as well as present in many medicines, namely antacids. Calcium is required for vascular contraction, vasodilation, muscle function and nerve transmission. The vast majority of the calcium in the body is stored in the bones and teeth.
Dairy products are the food sources highest in calcium; these include milk, cheese and yogurt. Top non-dairy sources of calcium are canned sardines, turnip greens, kale, bok choi and broccoli. There are much lower concentrations of calcium in these leafy greens than there are in dairy.
Calcium carbonate, one of the available forms of calcium, can be used to neutralize stomach acid. Due to this it is very prevalent in over the counter antacids.
Consuming low quantities of calcium results in no noticeable symptoms in the short term, but over time inadequate calcium can result in osteoporosis. Groups at highest risk of calcium deficiency are postmenopausal women, individuals with lactose intolerance or dairy allergy, and vegans who don’t consume dairy products.
The most important role that calcium plays in the body is related to bone health. Bones keep growing through childhood and adolescence with maximum bone mass peaking around the age of 30. The greater the peak bone mass, the longer serious bone loss can be delayed as the aging process progresses. For this reason it is important that children, adolescents and young adults consume adequate calcium and Vitamin D. Approximately 10 million Americans have osteoporosis, around 80% of which are women.
Bone loss occurs as part of the natural aging process, when calcium intake is low or it is poorly absorbed the body uses stored calcium for its regular functions which leads to the breakdown and weakening of bones. Bone loss can affect anyone but women are at the highest risk due to the bone loss than accompanies menopause. The FDA has approved supplement labeling stating that “adequate calcium and Vitamin D as part of a healthful diet, along with physical activity, may reduce the risk of osteoporosis in later life”.
Observational and experimental studies are highly suggestive that calcium may provide a protective effect against colorectal cancer.
There are some potential risks of consuming too much calcium. Too much dietary calcium can cause constipation, while too much supplemental calcium can result in kidney stones. Studies have also shown that high intakes of calcium and dairy products may be associated with a higher risk of prostrate cancer, although thus far studies are inconclusive.
Chloride is an essential mineral that aids in nerve and muscle function, electrolyte balance and acid based balance. Sufficient chloride is easily obtained through a typical balanced diet.
Chloride is found in many foods in the modern diet, as it is a major part of sea salt and table. It is also present in some fruits and vegetables, including celery, tomatoes, lettuce and olives.
Chloride is an electrolyte, and if too little is consumed it can cause excess fluid loss through sweating, diarrhea and vomiting. Too much dietary chloride tends to be a much bigger problem in developed nations, as salt from processed foods is linked to a litany of health problems. These include increased blood pressure and hypertension, which can ultimately lead to congestive heart failure and kidney disease.
Magnesium is found naturally in many different foods, fortified in others and available as a supplement and in some medications. It plays roles in muscle and nerve function, blood pressure regulation and protein synthesis. Magnesium is also needed for energy production and the synthesis of DNA and RNA. The body stores relatively large amounts of magnesium, around half of which is stored in the bones.
Magnesium is present in a wide variety of different foods from both plant and animal sources. The process of refining grains tends to lower magnesium significantly. The foods with highest concentration of magnesium include almonds, cashews, peanuts, black beans, soymilk, spinach, whole wheat bread, peanut butter, potatoes, avocadoes, bananas, kidney beans, ground beef and chicken breast. Magnesium is also the primary ingredient in some laxatives and a secondary ingredient in heartburn medications.
Magnesium deficiency is relatively rare in healthy adults with varied diets as ingested magnesium is stored in the kidneys. Groups with the highest risk of developing magnesium deficiency include people with malabsorption disorders, chronic alcoholics, people with type 2 diabetes and older adults. All of these groups have varying issues with proper kidney function which leads to problems with processing dietary magnesium.
Higher intakes of magnesium have been shown to reduce blood pressure and the risk of developing coronary heart disease. It may also help to reduce the risk of stroke. Diets high in magnesium have also been shown through trials to significantly reduce the risk of developing type 2 diabetes, likely because magnesium plays a role in the metabolism of glucose. It also has been indicated in studies to play a beneficial role in helping to treat osteoporosis. Magnesium deficiency also may lead to the development of migraines, although studies are limited as to whether supplementation plays a role in their treatment.
There are no dangers from consuming too much magnesium from dietary sources as excess is excreted through the kidneys. Large supplemental doses of magnesium can cause diarrhea, nausea, vomiting, extreme hypertension and sudden cardiac arrest. There have been a few documented fatal cases of magnesium toxicity, so it important not to overuse it in its supplemental forms.
Potassium is found naturally in many foods and also available as a supplement. Potassium is absorbed in the small intestine at a rate of approximately 90%, and is excreted primarily through the urine. Potassium levels in the body are directly related to sodium levels, as sodium is responsible for regulating the body’s fluid levels. Potassium is found in all of the body’s tissues and is necessary for normal cell function.
Dietary potassium is available in a wide range of food sources, with the highest concentrations being found in plant based sources. Foods with the highest levels of potassium include apricots, bananas, prunes, raisins, acorn squash, lentils, potatoes, orange juice, kidney beans, spinach, chicken breast and tomatoes.
Low intakes of potassium can raise blood pressure, increase the risk of kidney stones and make it more likely that changes in sodium intake have a greater affect on blood pressure. Extreme deficiency leads to a condition called hypokalemia, in its milder form this condition is characterized by muscle weakness, fatigue, glucose intolerance and trouble breathing. At its most severe hypokalemia can result in cardiac arrest and death.
Sodium is found in nearly every food in the typical American diet. It serves several functions in the body, its most important function relates to balancing the body’s fluids. It also aids with muscle and nerve function. Sodium is processed through the kidneys, when there is too much of it in the diet it enters the bloodstream and can lead to elevated blood pressure. High blood pressure, also known as hypertension, is linked to a large number of chronic diseases including heart disease, stroke, dementia, metabolic syndrome and weakened or torn blood vessels.
Sodium is present in all processed foods, usually in large quantities. Over 90% of Americans consume more sodium than is recommended. It is an essential mineral for the body, but it is exceedingly rare not to consume enough of it in the developed world, and focusing on limiting intake is the best strategy for long term health.
Sulfur is an essential mineral that is found in many foods. It plays an important role in metabolism, and is also helpful in reducing inflammation. It also is a part of insulin, which is responsible for maintaining healthy blood sugar levels. Low sulfur levels in the body have also been linked to memory and attention issues.
Most of the sulfur in the body is found in the skin, muscles and bones. It is also present in cartilage.
Red meat is the best dietary source of sulfur, though it should be consumed in moderation to avoid other health problems. Other good sources of sulfur include eggs, poultry, dairy, broccoli, cabbage, kale, mustard greens, collards, arugula, garlic and onions.
Moderate sulfur deficiency is relatively common for those who follow a typical Western diet that is high in grains and processed foods. Symptoms of sulfur deficiency include fatigue, joint pain, problems concentrating, inability to handle stress and depression.
Phosphorus is a mineral that is present in some foods and available in supplement form, usually paired with others. Phosphorus is a component of cells, is a part of both DNA and RNA and is also responsible for balancing most of the body’s fluids. Phosphorus also plays a major role in bone and calcium metabolism; approximately 80% of the body’s phosphorus stores are concentrated in the bones.
Phosphorus is available in a wide variety of foods, both plant and animal products. The body is much better equipped to convert phosphorous from animal products into usable form. The best sources of dietary phosphorus include chicken, turkey, fish such as salmon and pollock, shellfish such as clams, shrimp and scallops, milk, cheese, sunflower seeds, pumpkin seeds, nuts, beans and lentils.
Phosphorus deficiency is very rare in the developed world. Some symptoms of phosphorus deficiency include stiffness of the joints, fatigue, anxiety, changes in body weight and breathing problems. The most common causes of deficiency include chronic alcoholism, diabetes, and eating disorders. It can take a long time for deficiency symptoms to appear, as the body will convert phosphorus stored in the blood and the bones into usable form, it is only after these stores have been depleted that serious deficiency sets in.
Chromium is a trace element that helps to aid insulin, the hormone that is critical to metabolism. Chromium is available in two different forms, one of which is found in foods and is necessary for life, and the other which is toxic and forms as a result of industrial pollution. Chromium is found in many foods, but is not concentrated in large amounts in any of them.
Chromium is found in small amounts in both plant and animal food sources. The foods with the highest amount of chromium include broccoli, potatoes, garlic, basil, beef, red wine, grape juice, turkey breast, and orange juice. The body does not absorb chromium very efficiently, it absorbs it better when consumed with Vitamin C and Niacin.
Chromium is widely available in supplements with claims that it helps to decrease body weight and increase muscle mass. Studies have shown some correlation, although the difference shown between chromium and placebo is rather negligible.
Copper is a trace mineral that is involved in metabolism, protein synthesis, proper immune function and the growth and development of bone and connective tissue. The body stores most of its copper in the liver.
Dietary copper is available from a wide spectrum of foods. Those with the highest concentration include seafood, organ meats, nuts, beans, lentils, whole grains, lemons, leafy greens and some fruits. Most healthy adults receive enough copper from foods if they have a relatively varied, balanced diet.
Copper deficiency is linked to a wide variety of health problems including osteoporosis, arthritis, cardiovascular disease and bone and connective tissue maladies. Those who are at the highest risk of copper deficiency include people with malabsorption disorders, chronic alcoholics, diabetics and those with eating disorders. Athletes may need to consume larger amounts of copper than the average population as they will metabolize it faster, and vegetarians are at higher risk of deficiency because it is more difficult to derive copper from plant based sources.
Excess copper can cause nausea and stomach problems, at higher levels copper is toxic and can cause oxidative damage and even death. Copper toxicity is usually caused by accidental ingestion of very large amounts, if the body is functioning properly excess dietary copper will be expelled through normal processes.
Fluoride is a trace mineral that occurs naturally in the body, and is found primarily in the teeth and bones. Fluoride’s main function is to discourage the onset of tooth decay.
The vast majority of fluoride comes from consuming water from community systems, to which it is added. It is found naturally in ocean water, so seafood contains it in some amount. There are also small amounts present in tea and gelatin. Fluoride deficiency leads to weaker bones and teeth and an increased risk of cavities.
Iodine is a trace element found in some foods, fortified in others and also available in supplement form. Its most important role in the body is to help promote regular functioning of the thyroid, which is responsible for protein synthesis and ensuring proper metabolism. Iodine is found in soil, which affects the iodine content of the food that is grown in it. Soil with diminished iodine is common in many parts of the world, table salt is regularly fortified with it to reduce the prevalence of deficiency.
Iodine is found in a variety of foods, many of which have widely varied amounts due to production techniques. The foods with the largest amount of iodine include seaweed, cod, shrimp, prunes, lima beans and iodized salt. Iodized salt and enriched grains tend to be the major sources of dietary iodine in the typical American diet. Salt manufacturers in the U.S. have been fortifying their product with iodine since the 1920s.
Iodine deficiency used to be very common in mountainous regions of the United States as well as around the Great Lakes, as those areas tend to have soils with low iodine content. Deficiency is now very uncommon in developed countries but remains a problem in much of the developing world. The groups of people who are most likely to consume insufficient iodine include those who live in areas with low soil iodine content, people who do not have access to iodized salt, and pregnant women.
Iodine is essential to proper fetal and infant development, so it is important that pregnant and breast feeding women consume sufficient levels. Severe iodine deficiency during childhood has been shown to reduce cognitive function as measured by IQ by 13 points on average. Even mild iodine deficiency in children can cause cognitive problems. Health problems related to too much iodine intake mirror those caused by insufficient intake, as it causes the thyroid to quit functioning properly.
Iron is a trace mineral that contributes to growth, development, and normal cell function. It is found naturally in foods, fortified in others and is also available as a supplement. Iron is major part of hemoglobin, which is a protein that transfers oxygen from the lungs to the body’s tissues. Most of the iron stored in the body is in the form of hemoglobin.
Iron is most prevalent in seafood and lean meats, smaller amounts are available in many different plant sources. Much of the dietary iron in the typical diet in the developed world comes from consumption of fortified grains and breads. The best dietary sources of iron include oysters, beef, sardines, tuna, chicken breast, beans, lentils, spinach, chickpeas and turkey. Most multivitamins, especially those formulated for women, contain 100% of the recommended daily value.
Iron deficiency on its own is fairly rare, it is usually combined with deficiency of other vitamins and minerals. There are several groups of people who are at risk of iron deficiency, they include pregnant women, infants and young children, menstruating women, people who are frequent blood donors, people with cancer and those with chronic heart problems.
Anemia is the most common condition associated with iron deficiency, it is fairly common in pregnant women and is associated with low birthweight, premature birth, and impaired behavioral and cognitive development. Anemia is also found in a significant number of infants and toddlers which leads to attention and social problems that can be irreversible.
Too much iron in the diet is rarely an issue in healthy adults, as it is easily digested. Too much supplemental iron can cause digestive issues, and in high enough doses has even been linked to death. Iron also interacts with several different prescription medications, and some medicines can deplete iron levels.
Manganese is a trace element that is found in some foods, fortified in others and also available as a supplement. It plays an important role in metabolism, bone formation and in the defense of free radicals in the body. Most of the manganese in the body is stored in the bones.
Dietary manganese is found in a wide variety of foods sources. Some of the best sources include almonds, pecans, pinto beans, oatmeal, brown rice, dark chocolate, shellfish, and leafy greens like kale and spinach.
Manganese deficiency is rare in the developed world. While rare, it does carry many side effects including skeletal problems, impaired growth, metabolic and fertility problems and problems maintaining proper glucose levels. Manganese deficiency is most likely to occur when there is an underlying chronic illness such as diabetes, epilepsy or osteoporosis.
Manganese is toxic when consumed in too large amounts. It is also present in some aerosols and metal compounds that can become airborne and be ingested into the lungs. If exposure is at high levels for an extended period of time it can lead to neurotoxicity, symptoms of which can include motor function and psychological problems. If exposure continues it can lead to death.
Molybdenum is a trace mineral found in many foods and available in supplements. It is used by the body to help metabolize proteins, it is also involved in conjunction with other minerals for many bodily functions including development of the nervous system and cell production. The majority of molybdenum in the body is stored in the liver, kidneys and bones.
Dietary molybdenum is found in both plant and animal sources. The amount of molybdenum found in plant sources can vary widely due to the amount of the mineral in the soil. The best sources of molybdenum include almonds, cashews, kidney beans, navy beans, liver, eggs, tomatoes, leafy greens, and whole grains.
Molybdenum deficiency is extremely uncommon and can be treated through supplementation. Molybdenum can be a byproduct of industrial production, and airborne molybdenum can have toxic effects on the body. Excess dietary molybdenum is generally easily expelled by the body, too much supplemental molybdenum can have many adverse effects, the most common being an increase in the frequency and intensity of gout.
Selenium is a trace mineral that is found in many foods, fortified in others and also available as a supplement. Most of the body’s selenium is stored in the skeletal muscles. It plays and important role in many different functions including DNA synthesis, thyroid metabolism, reproduction and protecting from infection.
Dietary selenium is found in a variety of foods, the best sources tend to be seafood and organ meats. The foods with the highest levels of selenium include Brazil nuts, ham, halibut, tuna, shrimp, beef steak and liver, turkey, sardines, chicken and brown rice.
Selenium deficiency is extremely rare in the U.S., and by itself it rarely leads to any symptoms. Deficiency can make the body more susceptible to certain diseases, and chronic deficiency has been linked to male infertility in regions where selenium levels in the soil are low. Kidney dialysis can lead to lower levels of selenium, as the dialysis process removes selenium from the blood. People with HIV are also more likely to have low selenium levels due to malabsorption.
Selenium has been shown in some studies to reduce the occurrence of certain forms of cancer, this is due to its role in the immune system as well as its antioxidant properties and role in DNA repair. It also reduces inflammation keeps blood platelets from building up which helps to prevent cardiovascular disease. Some studies have also shown that selenium supplementation may help to treat or prevent cognitive decline and related diseases like Alzheimer’s, although results are mixed.
Excessive selenium intake can lead to hair loss and brittle nails. If a large enough quantity is consumed in a short period of time toxicity can occur, symptoms of which include respiratory issues, kidney and heart failure. This is extremely rare, but has been documented as having happened from supplements that mistakenly had several hundred times the recommended daily upper limit.
Zinc is an essential trace mineral that is found in some foods, fortified in others and available as a supplement. Its major function in the body is its role in cellular metabolism. It is also involved in immune function, DNA synthesis, cell division and protein synthesis. The body does not store zinc, so a steady supply from either the diet or supplements is necessary for proper health.
Zinc is found in a variety of foods, with shellfish, meat and poultry providing the largest amounts per serving. The best dietary sources of zinc include oysters, chuck roast, crab, lobster, ground beef, chicken, cashews, pork chops, chickpeas, kidney beans and flounder. There are very few plant-based sources of zinc unless they are fortified.
Symptoms of zinc deficiency include loss of appetite, slowed growth and problems with the immune system. Severe deficiency can cause sexual problems, hair loss, weight loss and lethargy. Since these symptoms can be associated with many other health problems it is not easy to attribute them to zinc levels. Zinc is also dispersed throughout the body and not stored at high levels, making it rather difficult to accurately test. Groups at highest risk of zinc deficiency include vegetarians and vegans, chronic alcoholics and those with malabsorption disorders.
Some studies have shown that when zinc supplements in the form of lozenges are taken at the first sign of symptoms of the common cold that they can speed recovery. These studies have also been refuted, so more study is needed to determine conclusively. Zinc also plays a role in slowing the advancement of age related macular degeneration, although it has only been shown to slow the process once it has already started and does not appear to be able to halt its formation in the first place.
Consuming too much zinc can lead to toxicity, and too much zinc can also lead to problems with absorbing dietary copper. Several adverse health effects are related to supplemental zinc, so it is recommended that diligence is used to make sure that adequate zinc is consumed through diet.