CHAPTER 10 LESSON 3: MINERALS

Osteoporosis

A condition of weakened bones where bones lose their density - calcium is a key piece of bone structure and calcium deficiency can lead to osteoporosis.

Calcium

A mineral that is required for life and helps the body build bones and maintain their strength. The levels of calcium in the blood are very tightly controlled, with levels of calcium ranging between 8.4 to 9.5 mg/dL. Vitamin D is involved in the active absorption of calcium from the digestive tract and absorption of calcium varies with the amount of calcium consumed.

Copper

Copper is an essential mineral and helps balance the redox system in the human body. There are several disorders that come from copper metabolism issues. For example, Menkes disease results in seizures, brain atrophy, and hypotonia and is corrected by early copper supplementation. Copper is needed in minute quantities, ranging from 600 to 700 micrograms (0.6 to 0.7 milligrams) per day. Copper deficiency is exceedingly rare in humans and, in most cases, copper is consumed in adequate quantities in most dietary patterns.

Dietary iron is found in two major forms: heme and nonheme iron.

Heme iron is derived from animal sources and is primarily made of hemoglobin and myoglobin. Nonheme is obtained from plants and other iron-fortified foods. While heme iron contributes roughly 15% of the total dietary iron intake, it contributes to more than 40% of all absorbed iron

Redox System

The process and reaction between two substances in which one substance is oxidized and the other reduced.

Hypothyroidism

A condition in which your thyroid does not produce enough thyroid hormones.

Trace Element

An element that is only required in minute amounts in the human body.

Fluoride

Fluoride is a nonessential mineral that, when consumed in low quantities, can be considered a beneficial ingredient for preventing cavities in teeth. Fluoride is found primarily in drinking water in the United States: roughly 52% of drinking water contains 0.7 to 1.2 mg/L of fluoride While low doses of fluoride can reduce the risk of cavities, higher doses consumed chronically (>2mg/kg) can result in mottled and pitted tooth enamel. Furthermore, ingestion of 10 to 25 mg/day for extended periods of time (7 to 20 years) can damage bones. Currently, fluoride insufficiency is uncommon in humans and, in most urban and rural places, fluoride toxicity is rare and does not need to be a cause of concern.

Mineral Functions and Sources

Food For Thought Minerals are found in high quantity in beef, shellfish, legumes, nuts, and root vegetables grown in mineral-rich soil. Supplementation is not necessary for minerals in most populations.

Common Food Sources of Minerals

Minerals are found in a wide range of foods, coming from both plant and animal sources. Minerals are found in the highest quantities in dairy (e.g., milk, yogurt, eggs, and cheese), beef, shellfish, whole grains, and dark, leafy greens

Goiter

The swelling of the neck resulting from enlargement of the thyroid gland.

Distribution of Magnesium in body

magnesium is found in large quantities in the human body, with roughly 20 to 30 grams found in the average adult human. It is distributed as follows: 60% is found in bone tissue, 20% in skeletal muscle, 19% in other soft tissues (e.g., heart, liver, and lungs), and less than 1% is found in extracellular fluid

Mercury

A trace element that finds its way into the human diet, has no necessary function, and is highly toxic, especially during development in utero and early childhood. *maximal daily intake of mercury recommended by the World Health Organization (2017) is 2 µg/kg per day. Mercury exerts its toxic effects primarily via the displacement of selenium

Use USDA Guideline examples to ensure adequate minerals are ingested: While mineral metabolism is complex, applying this knowledge into the real world can come down to very-basic principles. Ensuring someone obtains adequate minerals in their diet falls in line with the same practical advice for ensuring adequate vitamin intake: consuming a well-balanced diet that is rich in fruits and contains some animal meats or animal by products. Furthermore, understanding the varying mineral profiles of different foods and eating a variety of different mineral rich foods can ensure that an individual does not miss key nutrients found in some foods and not others. There are several simple actionable steps that can be taken to help individuals obtain adequate micronutrients.

Consume three to seven servings of green, leafy vegetables per week. Consume fish on a weekly basis. Consume three to seven servings of mineral-rich tubers (e.g., potatoes and turnips) per week. Consume three to seven servings of legumes and/or whole grains per week. Consume three to seven servings of lean cuts of animal meat and/or dairy products per week.

Nonessential Mineral

Minerals that are not required for human function and/or optimal health.

Hypokalemia

A condition where the concentration of potassium in the blood drops below normal levels. *Severe potassium deficiency, known as hypokalemia, can be deadly and cause cardiac arrest. Similarly, hyperkalemia can also result in cardiac arrest (Jain et al., 2012). Potassium deficiency is rare in otherwise healthy adults without established kidney disease. There has been some discussion that potassium may prevent cramps; however, this has not been supported by scientific literature.

Hyponatremia

A condition where the concentration of sodium in the blood drops below normal levels - this often happens when people sweat a lot or consume too much water and not enough electrolytes. The increased need is primarily due to loss of sodium through sweating (evaporative cooling). Insufficient sodium intake in athletes leads to hyponatremia, which sets in at concentrations below 135 millimolar. Hyponatremia can lead to malaise, nausea, cramps, headache, and slurred speech, with extreme cases leading to cardiac arrest and death. While it is well-accepted that many athletes have a higher need for sodium intake than the general population, athlete specific RDIs have not been established.

Potassium

A mineral that is present in all tissues in the body and is required for maintaining concentration gradients, fluid volume, and cardiac rhythm. Potassium is present in relatively large quantities, with roughly 140 grams residing in a grown adult. Most potassium is present inside of cells with small amounts in circulation, with the ratio of intracellular to extracellular potassium being 30:1.

Sodium

A mineral that is present in virtually every tissue of the body and is essential for maintaining gradient balance, fluid status, and cardiac rhythm. Where sodium differs from potassium is in its location. Sodium is primarily an extracellular fluid compared to potassium which is primarily an intracellular fluid

Magnesium

A mineral that is required for energy production, oxidative phosphorylation, and glycolysis. is involved in over 300 biochemical reactions that span the full spectrum of human metabolism: from digestion to nervous system activity to glucose regulation and protein synthesis. *A recent meta-analysis also showed that magnesium supplementation lowered fasting glucose, LDL-c, and triglycerides and raised HDL-c in people with Type 2 diabetes (Verma & Garg, 2017). Magnesium should be given special attention in your diet and individuals should consume magnesium-rich foods such as whole grains, cocoa, spinach, and nuts. Supplementation can also be considered in individuals with very-low levels of magnesium.

Zinc

A mineral that provides structure to cells and helps reactions occur - it is the most abundant intracellular of the trace elements and plays regulatory roles in transcription via transcription factors, stabilizes nucleic acids, and is neccesary for the creation of tubulin, giving cells their internal rigid structure and allowing them to properly maintain their shape and function. Overt and severe zinc deficiencies are known to cause substantial health issues: alopecia, immune deficiencies, night blindness, delayed wound healing, and growth retardation. Mild zinc deficiency may lead to impaired growth, which can be corrected through supplementation. Zinc deficiencies range from less than 1% to greater than 25% across the world, with the highest rates of zinc deficiency observed in Sub-Saharan Africa and South Asia (Wessells & Brown, 2012). There is also some evidence that high intakes of zinc, especially via supplementation, can result in copper deficiency

Chromium

An essential trace mineral that can improve insulin sensitivity and enhance macronutrient metabolism. Chromium is considered a trace element as the required intake is low (0.2 to 45 micrograms per day). There are two major forms of chromium: chromium 3+ (trivalent) and chromium 6+ (hexavalent). Chromium 3+ is the form found in food and is the biologically active form while chromium 6+ is a toxic form that results from industrial pollution.. *Chromium has been implicated in regulating insulin signaling, with some data suggesting that it may enhance insulin sensitivity and/or decrease insulin resistance (Cefalu et al., 1999). Chromium works to improve insulin signaling by modulating chromodulin, a protein that augments the signaling of insulin receptors. While it is difficult to link chromium deficiency to diabetes or diseases of insulin resistance, there are several pieces of evidence to suggest that chromium, as a mineral, is likely involved to some extent in the development of diabetes

Which mineral can be found in all of the following food sources: dairy, seafood, whole grains, and green leafy vegetables? Check all that apply Selenium Calcium Sodium Iron Potassium

Calcium

Match the minerals with their bodily functions. To begin, click an item in the left column. Then, click the matching answer in the column on the right.

Chromium - Involved in insulin signaling Magnesium - Involved in over 300 biochemical reactions including metabolism, digestion, nervous system activity Phosphorus - Required for energy production and maintaining cellular viability Sodium - Regulates fluid volume and the electrochemical gradient in the body Calcium - Most abundant mineral and is essential in stimulating muscle contractions Iron - Carries oxygen and plays a central role in the electron transport chain Potassium - Regulates fluid volume as well as maintaining cardiac rhythm Selenium - Serves as antioxidants or in the regeneration of antioxidants Zinc - Provides structure to cells and is involved with catalytic reactions

Sodium and Body Tissue

For comparison, the extracellular concentration of sodium is between 136 and 151 millimolar, whereas potassium is between 3.4 and 5.2 millimolar. Sodium deficiency is virtually unheard of in the developed world, with average intakes of sodium being roughly three to five times the RDA (Institute of Medicine, Board on Population Health and Public Health Practice, Food and Nutrition Board, & Committee on the Consequences of Sodium Reduction in Populations, 2013). Like the micronutrient iron, sodium is well-understood in terms of athletic performance as is the increased need for sodium among athletic populations.

Role of iron in athletic performance.

Given the substantial role that iron plays in metabolism, specifically oxygenation and aerobic metabolism, and the relatively high prevalence of iron deficiency, there has been a substantial body of research examining the effect of iron supplementation on athletic performance. Much of the literature is focused on repletion of iron in iron-deficient women. These studies demonstrate that in iron-deficient but not anemic women, supplementation with iron improved their ability to adapt to aerobic exercise (Brownlie, Utermohlen, Hinton, & Haas, 2004; Brownlie, Utermohlen, Hinton, Giordano, & Haas, 2002; Brutsaert et al., 2003). This indicates that iron likely plays a role in athletic performance and athletes, especially female endurance athletes, should be tested for iron deficiency. Coach's Corner Research indicates that correcting iron deficiency through supplementation (and potentially dietarily through food) can improve athletic performance. This does not mean supplementation above and beyond or if one is not deficient will help improve athletic performance.

Iron

Iron is central in hundreds of metabolic processes, with the storing, transporting, and delivery of oxygen via hemoglobin and myoglobin being the most important of its myriad roles. Iron is also involved in the electron transport chain and neurotransmitter production. Iron deficiency prevalence varies from 5% in North America to upwards of 60% in Africa and is responsible for roughly 50% of all cases of anemia (Stoltzfus, 2003). Iron deficiency is the primary cause of anemia, a condition in which your body does not have enough healthy red blood cells to transport oxygen

Magnesium and Type 2 Diabetes

Magnesium is conjugated to ATP; most ATP in the human body is found as MgATP. It is also intimately involved in the metabolism of carbohydrates, fats, and proteins and in the ion channels that regulate calcium flux and potassium flux across membranes. Additionally, evidence over the last 20 years has highlighted the role of magnesium insulin resistance. Magnesium is important in many chronic diseases, specifically diabetes. People with Type 2 diabetes are more likely to have lower levels of serum magnesium and supplementation with magnesium has been shown to improve glucose metabolism and markers of insulin sensitivity

Phosphorous

Phosphorus is found everywhere in the body and is required for energy production and maintaining cellular viability. Phosphorous is the central molecule in phosphate, which is part of adenosine triphosphate (ATP), the energy molecule that facilitates virtually every biochemical reaction. Phosphorous deficiency is exceedingly rare in the United States and does not appear to be a major concern in most health conditions. There is some evidence that excessive phosphorous intake from processed foods may increase the risk of cardiovascular disease and osteoporosis and accelerate established kidney disease; however, these data are mostly observational in the broad public, with the exception being kidney disease. In people with kidney disease, the ability to clear excess phosphorus from the body is impaired and elevated levels of phosphorous are associated with increased risk of progression to end-stage renal disease *Currently, there is no evidence that phosphorus supplementation improves athletic performance; it does not need to be supplemented or a major focus for performance nutrition

Selenium

Selenium The key component of several selenoproteins that serve as antioxidants or in the regeneration of antioxidants. Specifically, thioredoxin reductase and glutathione peroxidase are selenoproteins. Mercury exerts its toxicity in the human body by displacing selenium and substantially impairing the antioxidant systems in the body. Currently, selenium deficiency is incredibly rare in developed countries, but it is projected to become a larger issue as soil becomes depleted of selenium in the coming decades

Iodine

Similar to chromium, iodine is considered a trace mineral that is found in some foods and is supplemented in many others such as iodized salt. The primary function of iodine in the human body is as a precursor to thyroid hormones: both T3 and T4 (Figure: Function of Iodine). Iodine deficiency varies in prevalence due to geographic location as there are varying levels of iodine in the soil throughout the world. The most prevalent complications of iodine deficiency are goiter and hypothyroidism (Zimmermann, 2009). *Iodine deficiency and goiter were common in the Midwest United States through the early 1920s until iodized salt was made available in 1924 (Leung, Braverman, & Pearce, 2012). Iodine is critical to maintain proper thyroid function. In people who consume low-sodium/low-salt diets, careful attention should be given to ensuring adequate iodine intake.

Try This Make a list of all the foods that contain water-soluble vitamins, fat-soluble vitamins, and minerals and develop a personal shopping list of foods that are high in all micronutrients and of which foods help clients consume all of them. This can be a weekly grocery list to use with clients.

Source: U.S. Department of Agriculture (n.d.). Vitamins and Minerals. National Agriculture Library. Retrieved from https://www.nal.usda.gov/fnic/vitamins-and-minerals

Mercury Levels in Fish

The largest source of dietary mercury is from seafood, including fish and shellfish. Mercury concentrations increase the further one goes up the food chain. Fish and shellfish that consume smaller fish with mercury in their blood and tissue store more mercury per tissue volume than smaller fish. As such, fish such as sharks, swordfish, and tuna have higher levels of mercury than smaller fish such as mackerel