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Chapter 12: Minerals

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What Are Minerals? Inorganic elements essential to the nutrition of

humans Fourteen minerals are essential to body function

• Play several key roles in overall health and well being- Help chemical reactions take place in cells- Help muscles contract- Keep the heart beating

Two groups• Major minerals• Trace minerals

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What Are Minerals? Major minerals

• Need to consume > 100 milligrams per day• At least 5 grams of the mineral in the body• Calcium, sodium, potassium, chloride, phosphorus,

magnesium, and sulfur

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What Are Minerals? Trace minerals

• Need to consume > 20 milligrams per day• The body contains less than 5 grams total• Iron, zinc, copper, selenium, chromium, iodide,

manganese, molybdenum, and fluoride

Figure 12.1

The Minerals in Your Body

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Minerals Do not contain carbon Contain only atoms of the same element Are most often found

• As individual ions• In organic compounds

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Minerals Remain intact during digestion Generally do not change shape or structure when

performing biological functions Most minerals absorbed from the diet are in the form

of water-soluble salts Are not destroyed by heat, acid, oxygen, or ultraviolet

light Mineral bioavailability: Degree to which a nutrient

from food is absorbed and utilized in the body

Mineral Bioavailability

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Mineral Balance Body maintains tight control over mineral balance

• GI tractRegulates absorption from food based on the

body’s needMinerals in gastric juices and that slough-off

intestinal cells are either excreted in the feces or reabsorbed through the large intestine

• KidneysExcretes excess and reabsorbs the minerals when

the body needs them

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Mineral Functions Minerals work together to perform important

functions in the body• Fluid and electrolyte balance• Blood formation• Building healthy bones• Maintaining a healthy immune system

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Minerals Help Maintain Fluid Balance Minerals play a key role in fluid balance in the cells

• Extracellular minerals – sodium and chloride• Intracellular mineral – potassium with the help of

calcium, magnesium, and sulfur

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Mineral Participate as Cofactors Cofactor – substance that helps catalyze a reaction Minerals serve as cofactors in

• Antioxidant systems• Energy production• Muscle contraction• Nerve transmission

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Minerals Make Up Bones and Teeth Minerals make up the crystalline structure

(hydroxyapatite) that gives strength to bones and teeth• Major minerals

- Calcium, phosphorus, and magnesium• Trace mineral

- Flouride

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Minerals Can Be Toxic If ingested in high amounts, minerals can be toxic;

however, mineral toxicity is rare Toxicity most often seen with

• Large amounts of supplements• Certain conditions that interfere with the body’s

adaptive abilities Toxicity not generally seen from excess dietary intake

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Quick Review Minerals

• Inorganic nutrients • Are classified as either major or trace base on amount

found in the body and the amount needed daily• Bioavailability is based on nutritional status and

mineral binding• Play a vital role in numerous body functions

- Bone and blood health- Fluid balance- Cofactors in energy production and muscle

contraction- Nerve transmission

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Quick Review Continued Mineral toxicity

• Rare- Most people do not ingest overly high amount

from food- Body adjusts absorption and excretion

• Occurs with ingestion of high doses of supplements