HUN1201 Chapter 13
What are the roles of chromium in the body?
Chromium helps maintain glucose homeostasis by enhancing the activity of the hormone insulin. When chromium is lacking, a diabetes like condition may develop, with elevated blood glucose and impaired glucose tolerance, insulin response, and glucagon response. Some research suggests that some chromium supplements lower blood glucose or improve insulin responses in type 2 diabetes, but findings have not been consistent.
What is iodine?
traces of iodine are indispensable to life. In the GI tract, iodine from foods become iodide which is readily absorbed.
What is selenium recommendations and sources?
found in the soil and therefore in the crops grown for consumption. Eating as few as two Brazil nuts a day can effectively improve selenium statues.
What is manganese recommendations and sources?
grain products make the greatest contribution of manganese to the diet. an AI was set based on average intakes.
What is zinc transport?
After being absorbed zinc eventually reaches the pancreas. Here it is incorporated into many of the digestive enzymes that the pancreas releases into the small intestines at mealtimes. The small intestines thus receives two doses of zinc per meal 1. with food 2. from zinc rich pancreatic juices The recycling of zinc in the body from the pancreas to the small intestine and back to the pancrease is referred to as the enteropancreatic circulation of zinc. The body loses zinc primarily in feces. Smaller losses occur in urine, shed skin, hair, sweat, menstrual fluids, and semen. Numourous proteins participate in zinc transport. Zinc's main transport vehicle in the blood is the protein albumin. SOme zinc also binds to transferrin.
What are the roles of copper in the body?
Copper is a constituent of several enzymes which have diverse metabolic roles with one common characteristic: all involve reactions that consume oxygen and oxygen radicals. Other copper enzymes help to manufacture collagen, inactivate histamine, and degrade serotonin. Copper is needed in many of the reactions involved in energy metabolism.
What is copper deficiency and toxicity?
Deficiency is rare in the US. Copper may contribute to cardiovascular disease in humans. Some genetic disorders create a copper toxicity, but excess intakes from foods are unlikely. Excessive intakes from supplements may cause liver damage and therefore a UL has been set. Two rare genetic disorders affect copper statues in opposite directions. 1. Menkes disease - the intestinal cells absorb copper but cannot release it into circulation causing a life threatening deficiency. Treatment is getting copper intravenously. 2. Wilson's disease copper accumulates in the liver and brain creating life threatening toxicity. Treatment includes reducing copper intake, using chelating agents such as pennicillamine and taking zinc supplements which inhibit copper absorption.
What is iodine toxicity?
Excessive intakes of iodine can interfere with thyroid functions and enlarge the gland. Toxicity during pregnancy is especially damaging to the developing infant. An infant exposed to toxic amounts of iodine during gestation may develop a goiter so big it blocks the airway and causes suffocation. The UL is 1100 micrograms per day for an adult.
.What is iron recommendation?
For men is 8 mg daily women 18 mg daily Vegetarians need 1.8 times the iron to make up for the low bioavailability of the foods in their diets.
What is selenium toxicity?
High doses of selenium are toxic. A UL has been set. Causes loss and brittleness of hair and nails, garlic breath odor and nervous system abnormalities.
What is zinc toxicity?
High doses of zinc may cause vomiting, diarrhea, headaches, exhaustion and other symptoms. UL is set at 40 mg.
What is iron contamination?
In addition to the iron from foods, contamination iron from nonfood sources of inorganic iron salts can contribute to the day's intakes. The more acidic the food and the longer its cooked in iron cookware, the higher the iron content. The iron content of eggs can triple in the time it takes to scramble them in an iron pan.
What is zinc supplementation?
In developing countries zinc supplementation plays a large role in effectively reducing the incidence of disease and death associated with diarrhea and pneumonia. Zinc lozenges may shorter the duration but not the severity of common cold symptoms.
What is zinc deficiency?
In the developing world, nearly 2 billion people are zinc deficient. Children have high zinc needs because they are growing rapidly and synthesize many zinc containing proteins. Zinc deficiency involves severe growth retardation and immature sexual development. It also hinders digestion and absorption, causing diarrhea which perpetuates malnutrition. Infections are more likely because it hinders the immune response. Chronic zinc deficiency damages the central nervous system and brain leading to poor motor development and cognitive performance. Because zinc deficiency directly impairs vitamin A metabolism, vitamin A deficiency is often also present. It also disturbs thyroid function and the metabolic rate. It alters taste, causing loss of appetite and slows wound healing.
What are interactions with trace minerals?
Interactions among the trace minerals are common and often well coordinated to meet the body's needs. At other times it can lead to nutrient imbalances. An excess of one may cause a deficiency of another or may interfere with work of another. A deficiency of a trace mineral may even open up the way for a contaminant mineral to cause a toxic reaction. A good food source of one mineral may be a poor food source of another and factors that enhance the action of some trace minerals may interfere with others.
What are the roles of iodide in the body?
Iodide is an integral part of the thyroid hormones that regulate body temperature, metabolic rate, reproduction, growth, blood cell production, nerve and muscle function and more. By controlling the rate at which the cells use oxygen, these hormones influence the amount of energy expended during basal metabolism.
What are the roles of iron in the body?
Iron can serve as a cofactor to enzymes involved in the numerous oxidation-reduction reactions that commonly occur in all cells. Enzymes involved in making amino acids, collagen, hormones, and neurotransmitters all require iron. Iron also forms a part of the electron carriers that participate in the electron transport chain. These carriers transfer hydrogens and electrons to oxygen forming water and in the process making ATP for the cells' energy use. Most of the body's iron is found in two proteins: hemoglobin in red blood cells and myoglobin in the muscle cells. In both, iron helps accept, carry, and then release oxygen.
What is iron deficiency and anemia?
Iron deficiency and iron deficiency anemia are not the same thing. People can be iron deficient without being anemic. Iron deficiency anemia refers to the sever depletion of iron stores that results in a low hemoglobin concentration. Without adequate iron, red blood cells cannot carry enough oxygen from the lungs to the tissues. The result is fatigue, weakness, headaches, apathy, pallor and poor resistance to cold temperatures. People with anemia only feel fatigued when they exert themselves. Iron supplements can reduce the fatigue and allow for more physical activity.
What is assessment of iron deficiency?
Iron deficiency develops in stages which are: 1. iron stores diminish 2. decrease in transport iron 3. lack of iron limits hemoglobin production
What is iron poisoning?
Large doses of iron supplements cause GI distress including constipation, nausea, vomiting, and diarrhea. The UL of iron is 45 mg per day for adults. Ingestion of iron containing supplements is a common cause of accidental poisoning in young children. Symptoms include: 1. nausea 2. vomiting 3. diarrhea 4. rapid heart rate 5. weak pulse 6. dizziness 7. shock 8. confusion As few as five iron tablets containing as little as 200 mg of iron have cause deaths in young children.
What is the correlation between selenium and cancer?
Limited research suggests that the antioxidant action of selenium may protect against some types of cancers. Selenium supplements, however, have not proved effective in preventing cancer and in fact may damage DNA and cause harm.
What is Manganese deficiency and toxicity?
Manganese requirements are low and many plant foods meet the amount needed so deficiencies are rare. Dietary factors such as phytates inhibit its absorption. High intakes of iron and calcium limit manganese absorption, so people who typically have these supplements may inhibit their manganese absorption. Manganese toxicity is more likely to occur from a contaminated environment than from excessive dietary intake. A UL has been established based on foood, water, and supplements.
What are iron food sources?
Meets, fish, and poultry contribute the most iron per serving. Legumes and eggs are also a good source of iron. Milk products are notoriously low in iron. The FDA does not mandate iron enrichment but most states require manufacturers to enrich flour and grain products with iron.
Iron deficiency and behavior?
Mental productivity and physical activity goes down. Thus, people simply do less. They have no obvious deficiency indicators, they just are unmotivated and more apathetic. Many of the symptoms associated with iron deficiency are easily mistaken for behavior and motivational problems.
What is toxicities of trace minerals?
Most of the trace minerals are toxic at intakes only two and a half to eleven times above the current recommendations. It is important not to habitually exceed the UL of recommended intakes. Many dietary supplements have trace minerals making it easy for users to exceed their needs.
What is iron supplementation?
People who are iron deficient may need supplements as well as iron rich, absorption enhancing diets. Many physicians routinely recommend iron supplements to pregnant women, infants, and young children. Iron from supplements are not as easily absorbed as the iron from foods so the doses must be higher. Absorption also improves when supplements are taken between meals, at bedtime on an empty stomach, or with liquids.
What is copper recommendations and sources?
Richest food sources of copper are legumes, whole grains, nuts, shellfish, and seeds. More than half the copper from foods is absorbed and the major route of elimination appears to be bile. Water may also provide copper, depending on the type of plumbing pipe and the hardness of water.
What are the roles of selenium in the body?
Selenium is one of the body's antioxidant nutrients working primarily as a part of proteins. Glutathione peroxidase is the most notable protein that selenium works with and it works in tandem with Vitamin E. Glutathione peroxidase prevents free radical formation. if free radical do form, vitamin E stops them. Some selenium containing enzymes selectively activate or inactivate the thyroid hormones.
What are deficiencies of trace minerals?
Severe deficiencies of the better known minerals are relatively easy to recognize. Deficiencies of the others are relatively hard to recognize and mild deficiencies are easily overlooked. Deficiencies can have wide reaching effects and can affect people of all ages. The most common result of deficiency in children is failure to grow and thrive.
What is iron and chronic diseases?
Some research suggests a link between heart disease and excess iron. Limited evidence suggests an association between iron and some cancers. The explanation for this is usually focused on free radicals. One of the benefits of high fiber diets may be that the accompanying phytates bind iron and make it less available for such reactions.
What is chromium supplements?
Some supplement advertisers have convinced people they can lose fat and build muscle by taking chromium picolinate. This remains controversial.
What is iron transport and storage?
The blood transport protein transferrin delivers iron to the bone marrow and other tissues. The bone marrow uses large amount of iron to make new red blood cells, whereas other tissues use less iron. Surplus iron is stored in the protein ferritin, primarily in the liver, but also in the bone marrow and spleen. When the concentrations of iron become abnormally high, the liver converts some ferritin into another storage protein called hemosiderin which releases iron more slowly. Storing excess iron in hemosiderin protects the body against the damage that free iron can cause. Free iron acts as a free radical, attackign cell lipids, DNA and protein. When red blood cells are removed from the blood and taken apart, the iron is saved where it attaches to transferrin and brought back to the bone marrow to be reused. The body does lose some iron daily through the GI tract, and if bleeding occurs. Only tiny amounts of iron are lost in sweat, urine and shedding skin. Hepcidin is important in that it helps to maintain blood iron within normal ranges. It limits absorption from the small intestine and controlls the release of iron from the liver,spleen and bone marrow. Hepcidin production increases in iron overload, and decreases in iron deficiency.
What is iron absorption?
The body conserves iron. It is regulated by absorption. If there is a deficit, more iron is absorbed, if there is a surplus, less iron is absorbed. The protein ferritin captures iron from food and stores iron in the cells of the intestines. When the body needs iron, it is released by ferritin to an iron transport protein called transferrin. If the body does not need iron, it is carried out when the intestinal cells are shed and excreted in the feces about every 3-5 days. Iron absorption depends in part by its dietary source. Heme iron is iron which is derived from flesh of animals, and nonheme iron is derived from plant derived and animal derived foods. Heme iron has a high bioavailability and is not influenced by dietary factors. In contrast several factors influence nonheme iron. Vitamin C also enhances nonheme iron absorption from foods eaten at the same meal by capturing the iron and keeping it in the reduced ferrous form, ready for absorption. Some dietary factors bind with nonheme iron inhibiting absorption which include: -phytates in legues, whole rains, and rice -vegetable proteins in soybeans, other legumes, and nuts -calcium in milk -polyphonols in tea, coffee, grain products, oregano, and red wine
What are trace minerals?
The body requires the trace minerals in minuscule quantities. They participate in diverse tasks all over the body, each having special duties that only it can perform
What is Manganese?
The human body contains a mere 20 mg of manganese. Most of it can be found in the bones and metabolically active organs such as liver, kidneys, and pancreas.
What is the role of fluoride in the body?
Where fluoride is lacking, dental carries are common. Drinking water is usually the best source of fluoride and 75% of the US population served by community water systems receive optimal levels of fluoride. Fluoridation of drinking water protects against dental carries and supports oral health. Most bottled waters lack fluoride.
What is iodine deficiency?
The hypothalamus regulates thyroid hormone production by controlling the release of the pituitary's thyroid stimulating hormone (TSH). With iodine defiiency, thyroid hormone production declines and the body responds by secreting more TSH in a futile attempt to accelerate iodide uptake by the thyroid gland. If this deficiency continues, the cells of the thyroid gland enlarge to trap as much iodide as possible. Sometimes it enlarges enough to cause a goiter (a visual lump in the neck). Goiter may be the earliest and most obvious sign of iodine deficiency, but the most tragic and prevalent damage occurs in the brain. Iodine deficiency is the most common cause of preventable mental retardation and brain damage in the world. Even in the US pregnant women may not get the iodine that they need. Severe iodine deficiency during pregnancy causes the extreme and irreversible mental and physical retardation known as cretinism.
What is iron overload?
The iron overload disorder known as hemochromatosis is caused by a genetic failure to prevent unneeded iron in the diet from being absorbed. The hormone hepcidin supports iron homeostasis and its deficiency or rarely resistance cuases hemochromatosis. Other causes of iron overload include repeated blood transfusions, massive doses of supplementary iron and other rare metabolic disorders. Some of the signs of overload are apathy, lethargy, and fatigue. Iron overload is characterized by a toxic accumulation of iron in the liver, heart, joints, and other tissues. Excess iron in these tissues causes free radical damage. Infections are likely because viruses and bacteria thrive on iron rich blood. Symptoms are most severe in alcohol abusers, because alcohol damages the small intestines further impairing its defenses against absorbing excess iron. Untreated iron overload increases the risks of diabetes, liver cancer, heart disease, and arthritis. Currently treatment involves phlebotomy, which removes blood from the body and chelation therapy which uses chelate (a substance that can grasp the positive ions of a mineral) to form a complex with iron and promotes its excreation. Iron overload is much more common in men than in women. Vitamin C is a prooxidant because it enhances iron absorption and releases iron from ferritin, allowing free iron to wreak the damage typical of free radicals.
What is iodine recommendations and sources?
The ocean is the world's major source of iodine. Kelp, seafood, water, and even iodine containing sea mist are dependable iodine sources. Inland, the amount is variable based on the soil. Seafood, vegetables grown in iodine rich soil, and iodized salt are great sources of iodine. In the US, food labels indicate if the salt is iodized.
What is zinc absorption?
The rate of zinc absorption varies from 15 to 40 percent, depending on the amount of zinc consumed. As zinc intake increases, the rate of absorption decreases and vice versa. Upon absorption into an intestinal cell, zinc has two options: 1. zinc may participate in the metabolic functions of the intestinal cell itself 2. zinc may be retained within the intestinal cells by metallothionein (a sulfer rich protein that avidly binds with and transports metals such as zinc) until the body needs zinc. Metallothionein plays a key role in storing and distributing zinc throughout the body.
What are the food sources for trace minerals?
The trace mineral contents of foods depend on soil and water composition and how foods are processed.
What are nonessential trace minerals?
Those minerals that are not essential don't have that much research about them. They are known to have positive affects on the body but the extent to which they are important is not known yet. The research is mainly done in animals.
What is fluoride toxicity?
Too much fluoride can damage the teeth causing fluorosis. a UL has been established for this reason.
What is iron deficiency?
Worldwide, iron deficiency is the most common deficiency. Iron deficiency anemia affects 1.5-2.0 billion people mostly preschool children and pregnant women. Also common among those who are overweight. Women during reproductive years are prone to iron deficiency due to the menstrual cycle. Also pregnancy demands additional iron that is often not met. Bleeding from any site increases iron losses. Even small chronic blood loss depletes iron reserves. People who donate blood regularly could also benefit from an iron supplement.
What is zinc recommendations and sources?
Zinc is highest in protein rich foods such as shellfish, meats, poultry, milk and cheese. Legumes and whole grain products in large quantities are a good source also. Vegetables vary in zinc depending on the soil they are grown in. Average zinc intake in the US is slightly higher than recommended.
What are the roles of zinc in the body?
Zinc supports the work of hundreds of proteins in the body which participate in a variety of metabolic processes and regulate gene expression. Zinc also stabilizes cell membranes and DNA helping to strengthen antioxidant defenses against free radical attacks. It also assists in immune function and in growth and development. Zinc participates in the synthesis, storage, and release of the hormone insulin in the pancreas although it does not seem to play a role in insulin's action. Zinc interacts with platelets in blood clotting, affects thyroid hormone function, and influences behavior and learning performance. It is needed to produce the active form of vitamin A (retinal) in visual pigments and the retinol binding protein that transports vitamin A. It is essential for normal taste perception, wound healing, sperm production, and fetal development. A zinc deficiency impairs all these and other functions, underlining the vast importance of zinc in supporting the body's proteins.
What is iron deficiency and pica?
a curious behavior seen in some iron deficient people especially in women and children of low income groups is pica. These substances contain no iron and cannot remedy a deficiency, in fact they can inhibit absorption of iron. The consequence of pica is anemia.
What is the role of Manganese in the body?
acts as a cofactor for many enzymes that facilitate the metabolism of carbohydrates, lipids, and amino acids. Also, manganese containing metalloenzymes assist in bone formation and the conversion of pyruvate to a TCA cycle compound.
What is molybdenum?
acts as a working part of several metalloenzymes. Dietary deficiencies of molybdenum are unknown because the amounts needed are so minuscule. Legumes, breads, and other grain products, leafy green vegetables, milk and liver are molybdenum rich foods. AI falls within suggested range of intakes. Toxicity is rare. UL has been established. Characteristics of toxicity include kidney damage, and reproductive abnormalities.
What is chromium?
an essential mineral that participates in carbohydrate and lipid metabolism. Has different charges.
What is selenium?
an essential mineral that shares some of the chemical characteristics of the mineral sulfur. This similarity allows selenium to substitute for sulfur in the amino acids methionine, cysteine, and cystine.
What is iron?
an essential nutrient, vital to many of the cells' activities but it poses a problem for millions of people. Iron demonstrates that too much or too little of a nutrient can be detrimental.
What is zinc?
an essential trace element required for numerous metabolic reactions. Virtually all cells contain zinc but the highest concentrations are found in muscle and bone.
What is selenium deficiency?
associated with Keshan disease. Keshan disease is a heart disease that is prevalent in regions of China where soil and foods lack selenium. Although the primary cause of this disease is probably virus or toxin, selenium deficiency appears to predispose people to it and adequate selenium seems to prevent it. Symptoms of selenium deficiency include impaired cognition and poor immunity.
What are contaminant materials?
impair body's growth, work capacity, and general health. they include the heavy metals lead, mercury, and cadmium which enter the food supply by way of soil, water and air pollution.
What are fluoride recommendations and sources?
much of the US population has access to water with an optimal fluoride concentration, which typically delivers about 1 mg per person per day. Fish and most teas contain appreciable amounts of natural fluoride.
What is chromium recommendations and sources?
present in a variety of foods. Best sources are unrefined foods, particularly liver, brewer's yeast, and whole grains. More refined the food the less chromium they have to ingest.
What is fluoride?
present in virtually all soils, water supplies, plants, and animals. The body contains only a trace of fluoride but with this amount, the crystalline deposits in teeth are larger and more perfectly formed.
What is copper?
the body contains about 100 mg of copper in a variety of cells and tissues. Copper balance and transport depends on a system of proteins.
What is pica?
the craving and consumption of ice, chalk, starch, and other nonfood substances.