Minerals for an Active Lifestyle

Minerals are essential to the human body’s growth and development. They can be obtained from food, fortified food products, and supplements. The body uses minerals to keep the bones, muscles, heart, and brain functioning properly, and also for creating enzymes and hormones (1). Humans need different amounts of each mineral in order to stay healthy. The specific amounts are defined by recommended daily allowances (RDA) (2).

There are two types of minerals: macro minerals and trace minerals. The body needs a larger amount of macro minerals and only small amounts of trace minerals. Some important macro minerals include calcium, phosphorus, magnesium, sodium, and potassium. Some trace minerals include iron, manganese, copper, iodine, zinc, chromium, and selenium (2).

Typically, people will acquire the right amount of minerals by eating a well-balanced diet. Sometimes, however, a doctor may recommend a supplement to people who have difficulty obtaining enough of a certain mineral or athletes who are more likely to use up their mineral pools through vigorous exercise.

Athletes tend to need more nutrients than those who are less active because they demand more from their bodies. The greater the intensity of the workout, the more nutrients the body needs. Distance cycling, marathons, triathlons, and ultra-marathons are all sports that require the athlete to greatly increase their nutrient intakes. Athletes should focus on getting enough calcium, iron, magnesium, potassium, selenium, sodium, and zinc.

CalciumCalcium is a macro mineral that is needed for healthy bones and teeth, nerve conduction, immunity to disease, blood clotting, production of energy and muscle contraction (3). It is the most abundant mineral in the body. According to the Mayo Clinic, the RDA for men 19-70 years old and women 19-50 years old is 1,000 mg a day; 1,200 mg is recommended for women 51 and older and men 71 and older. Female athletes, specifically, should be sure to consume enough calcium. Those who do not are at a greater risk of developing predisposed osteoporosis due to increased calcium loss from exercise (4). The body does not produce calcium, so it must be obtained through other sources. To fully absorb calcium, the body also needs vitamin D (5). Foods that contain calcium include dark leafy greens as well as soybeans and white beans (6).

There are many different forms of calcium, and some types are not as easily absorbed as others. If you choose to take a calcium supplement, it is important to look for a label that lists both elemental calcium, as well as total calcium. Elemental calcium is the amount of calcium actually absorbed by the body. The most commonly used (and least expensive) supplement is calcium carbonate, which has one of the highest concentrations of elemental calcium. Unfortunately, calcium carbonate is low in bioavailability, meaning the amount of calcium in the supplement that can actually be absorbed and assimilated by the digestive system. Calcium citrate is a supplement that is well absorbed by most people, has been proven to help bone density, and is believed to help reduce the risk of kidney stones. It is preferred by people with low levels of stomach acids, especially older people with bone issues. However, it has less elemental calcium and bioavailability (7).

MagnesiumMagnesium is a macro mineral that is essential for every major biologic process and the use of glucose in the body. It is required for the active transport of minerals like potassium and calcium across cell membranes (8). It is used for the synthesis of nucleic acids and protein, and cellular energy (3). Magnesium deficiency is not common in healthy people, however specific medications and health conditions can cause this issue. Some symptoms include numbness, tingling, muscle cramps, seizures, and abnormal rhythms of the heart (1).

Magnesium is found in legumes, nuts, seeds, green leafy vegetables, and whole grains (3). The RDA for adult males 19-30 years old is 400 mg and for females is 310 mg. Adult males 31 years and older have an RDA of 420 mg and females have an RDA of 320 mg (8). Magnesium supplementation is thought to potentially help manage hypertension, cardiovascular disease, and type 2 diabetes. While 43% of the U.S. population uses dietary supplements containing calcium, many are not balancing that with a proper amount of magnesium. Magnesium stimulates hormone calcitonin, which draws calcium out of the blood and soft tissues back into the bones and helps preserve bone structure. This helps lower the likelihood of osteoporosis, some forms of arthritis, heart attack, and kidney stones (9). The most common ratio of calcium to magnesium found in many cal-mag supplements is 2:1.

Unfortunately, due to the the high calcium, low magnesium diet common in the U.S., it is difficult to maintain the 2:1 ratio. Magnesium citrate powder is a supplement that is used by many people (9). Many medical professionals are also promoting magnesium as an important part of every athlete’s recovery process and the body’s utilization of glucose. Athletes who are magnesium deficient can experience low energy levels and issues with muscle function (10).

PotassiumPotassium is a macro mineral that plays an important role in many biological processes, muscle contraction, nerve impulses, synthesis of nucleic acids and protein, and energy production (3). Potassium can also help lower the blood pressure-raising effects of sodium. The more potassium that is consumed, the more sodium is passed through urine (12).

Potassium deficiency is most commonly caused by excessive loss of fluid through vomiting, kidney disease, or the use of certain medications. Symptoms include muscle cramping, weakness, constipation, bloating, and abdominal pain (1). The RDA for potassium in adults is 4,700 mg a day (11). While there are potassium supplements available over the counter, doctors recommend obtaining the mineral naturally. Fresh fruits and vegetables like bananas, avocados, and beets are the best sources of potassium (3). Because potassium is essential for human performance, athletes should be sure to obtain adequate amounts for optimal performance during workouts.

IronIron is a trace mineral that plays an important part in hemoglobin (a protein that carries oxygen to tissues), and other proteins and enzymes to keep the body healthy. Iron deficiency can lead to anemia, which causes people to feel weak and tired. The RDA for iron is 18 mg a day for women and only 8 mg a day for men (11). Beans, tofu, and lentils provide good sources of iron (1).

While many people get an adequate amount of iron in their diets, iron supplements are recommended for those who have anemia, are pregnant, have an infant, menstruate, exercise regularly, experience regular blood loss, are on dialysis, take iron depleting medication, have ADHD, or have ACE inhibitor associated cough. Supplements are available in capsule form and should be taken on an empty stomach because food may decrease the amount of the mineral that the body absorbs. Vitamin C can also help with the absorption of iron (13). It is important for athletes to consume enough iron because losing too much can cause iron-deficiency anemia, which will cause athletes to become fatigued during their workouts.

IodineIodine is a trace mineral essential to thyroid hormones, which regulate metabolism, growth, and development. Iodine deficiency can lead to goiter, hypothyroidism, slow metabolism, fatigue, and pregnancy-related issues. Iodine deficiency is a world health problem and the most common cause of goiter. The RDA for iodine is 150 mcg a day for both males and females. Sea vegetables, cranberries, and organic navy beans are a few great sources of iodine (15). Over 70 countries worldwide, including the US, have iodized salt programs. Salt manufacturers in the US have been adding iodine to table salt for almost 100 years. Many multivitamin/mineral supplements also have iodine in the forms of potassium iodide or sodium iodide (16).

Most humans can consume the proper minerals they need by eating a wide variety of food including fruits, vegetables, beans, nuts, and whole grains. Unfortunately, soil depletion is a common cause of mineral deficiency in fruits and vegetables. Because of modern intensive agricultural methods, the soil our food grows in has been stripped of increasing amounts of nutrients. This causes the food people eat to have smaller amounts of vitamins and minerals. Despite this, fruits and vegetables should still be consumed in large amounts on a regular basis. People who wish to eat foods with the highest amounts of nutrients should purchase organic foods from local farmers (17). Taking supplements can potentially help replace the minerals that have been lost. However, it is important to consult a doctor before starting any new supplements or medications.WF

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