Nutrition 4.4

Heme iron

- found in animal flesh in the form of hemoglobin or myoglobin - is easily absorbed

Iron status

- A person who is iron deficient will have increased absorption compared to an individual that has adequate iron stores. - In times of growth and pregnancy the body also naturally absorbs more iron.

Diet

- High fiber intake or pica (a disorder characterized by the persistent eating of non-nutritional substances such as dirt, hair, paint, ice, etc.) both adversely affects absorption. - Zinc supplements can also interfere

Fiber-mineral interactions

- High-fiber diets can lower the absorption of iron, zinc, and other minerals. - Phytic acid (phytate) in grain fiber binds to minerals and interferes with absorption.

Iron deficiency

- anemia develops - symptoms of anemia include pale skin, poor temperature regulation, fatigue, and loss of appetite. - infants, preschoolers and teenagers all going through rapid growth are at higher risk - Vegetarians also may require a supplement due to the lack of heme iron in their diet

Iron

- deficient in people everywhere - can be stored as a part of the hemoglobin molecule of red blood cells, in bone marrow, and in other cells. - Absorption is dependent on several factors including the type of iron, the body's specific need for iron, and an individual's diet

non heme iron

- defined as elemental iron that can be added to grain products and is found in vegetables, milk, eggs, and other plant products. - not easily absorbed - enhanced when combined with source of heme iron or vitamin C

Chromium

- enhances the transport of glucose across cells by aiding insulin function. - studies suggest low chromium intake may lead to the development of type 2 diabetes. - Chromium may also be involved in cholesterol synthesis, as a deficiency may lead to elevated cholesterol and triglyceride levels. - Sources include egg yolk, nuts, organ and other meats - Supplements are not advised as toxic levels can lead to liver damage and lung cancer.

Chloride

- found in some fruits and vegetables and table salt (like sodium contributes to increased blood pressure) - important for extracellular fluid control, immune function, and as a component of hydrochloric acid in the stomach

Copper

- important in the metabolism of iron, as a cofactor for antioxidants, connective tissue proteins, blood clotting, and immune functions. - absorbed in the stomach and small intestine -found in liver, seafood, legumes, nuts, dried fruits, cocoa, and whole grains.

Flouride

- inhibits bacterial activity in the mouth and prevents tooth decay. - strengthens the structure of bone and teeth and is important in the synthesis of tooth enamel. - Excess amount of fluoride can cause mottling, the presence of white or yellow spots on the teeth. Mottling occurs during tooth development and, for this reason, children are encouraged not to swallow toothpaste.

Phosphorus

- located primarily in the bone - important for bone structure and is also a component of ATP, DNA, RNA, and phospholipids. - deficiency is rare due to the variety of food sources as well as its high bioavailability. Meat, cheese, milk, and grains provide most of phosphorus in the diet. - Daily Value is 1000 mg

Mineral source

- minerals from animal products are better absorbed - dietary fibers in plants may hinder the body's ability to absorb certain minerals - Oxalic acid is found in dark green leafy vegetables and can decrease the absorption of certain minerals. - plant sources like grains may lose minerals during refining process

Vitamin- mineral interaction

- necessary for nutrient absorption and metabolism - For example, iron absorption increases when consumed with a good source of vitamin C.

Calcium

- necessary for teeth and bone structure, blood clotting, nerve impulse transmission, and muscle contraction - Tetany occurs when calcium levels fall too low—the muscles cannot relax after contracting and involuntary twitching occurs. - enhanced absorption: Blood levels of parathyroid hormone (PTH), the presence of glucose and lactose in the diet, infancy, and pregnancy -inhibit absorption: Large amounts of phytic acid in grains, excess amounts of phosphorus in the diet, vitamin D deficiency, diarrhea, and old age - Current recommendations are 1000 mg to 1200 mg

Zinc

- primarily found in muscle and bone - Most of the zinc in the diet comes from animal sources, such as beef, milk, and poultry. Whole grains, peanuts, legumes, and fortified breakfast cereals are also good sources. - plant fibers, calcium, copper, and iron supplements can decrease the body's capacity to absorb zinc. - important for DNA synthesis, as a cofactor for enzymes, wound healing, bone and sexual organ maturation, prevention of cell oxidation, and growth. - Deficiency symptoms include acne-like rash, diarrhea, hair loss, and a reduced sense of taste (hypogeusia) and smell (hyposmia).

Major Minerals

- required in amounts greater than 100 milligrams daily in our diet - sodium, potassium, chloride, calcium, phosphorus, magnesium

Trace Minerals

- required in amounts less than 100 milligrams daily - iron, zinc, selenium, iodide, copper, flouride, chromium

Iodide

- required to promote growth and development, to regulate metabolism, and for thyroid hormone synthesis - During World War I, a link between lack of iodide and goiter was discovered. Goiter is an enlargement of the thyroid gland. this exerts pressure on trachae making it hard to breath

Potassium

- responsible for fluid control operating inside the cells, nerve impulse transmission, and muscle contractions - Unprocessed foods, such as fruits, vegetables, whole grains, and low-fat dairy products, are good sources of potassium - helps lower high blood pressure. - A deficiency caused either by a poor diet or use of diuretics can result in muscle cramps, confusion, and cardiac arrhythmias. - current recommendations are 3500 mg daily.

Sodium

- table salt - important for fluid balance and nerve impulse transmission - human body absorbs almost all the sodium ingested - major concern is overconsumption - DASH: dietary approach to stop hypertension; high consumption of fruits, veggies, whole grains, low fat dairy and it naturally decreases sodium and lowers high blood pressure - 2300 mg

Magnesium

- throughout body, though greater than 60% is found in bone. - key component in the production of ATP, DNA, and RNA and necessary for hundreds of enzymatic reactions - deficiency can result in irregular heartbeats, weakness, muscle pain, and seizures. -plant products and milk and meat - toxicity due to overuse of antacids, supplements, and laxatives.

Selenium

-important as an antioxidant and contributes to thyroid hormone metabolism. - found in fish, meat, eggs, Brazil nuts, organ meats, and grain grown in soil containing selenium.

Mineral-mineral interactions

an excess in one mineral will result in decreased absorption of another mineral as they compete for absorption. For example, a calcium supplement and iron supplement should never be taken together.

Three hormones are responsible for controlling blood calcium levels:

calcitriol, PTH, and calcitonin.

Hemochromatosis

genetic condition that leads to increased iron absorption. Iron will build up to dangerous amounts in the heart, muscles, and pancreas leading to organ damage

Minerals

inorganic elements involved in body structure and regulation

two mineral groups

major and trace

Bioavailability can be affected by:

mineral source fiber-mineral interactions mineral-mineral interactions vitamin-mineral interactions