Minerals

Chapter 7

What are minerals?

• Inorganic molecules

• Essential for human survival

• No caloric value

• Not degraded by cooking or digestion

Mineral Classification

Major Minerals• Needed in amounts

> 100 mg• Common examples

– Sodium– Potassium– Calcium

Trace Minerals• Needed in amounts

< 100 mg• Common examples

– Iron– Zinc– Chromium

Major Mineral: Calcium

• Most abundant mineral• Functions:

– Blood clotting– Muscle contraction– Nerve transmission– Bone formation

• AI:– Men and women (19–

50 yo) = 1,000 mgSource: USDA

Major Mineral: Calcium (continued)

• Signs of deficiency:– Hypocalcemia

(rare)– Muscle spasms– Convulsions– Low bone density

• Symptoms of toxicity:– Hypercalcemia– Calcium deposits– Kidney stones– Fatigue– UL = 2,500 mg

• Are supplements needed?

Major Mineral: Phosphorus

• Functions:– Bone and tooth

formation– Cell membrane

formation– Enzyme activity

• AI:– 700 mg

Source: USDA

Major Mineral: Phosphorus (continued)

• Signs of deficiency:– Bone malformation– Bone pain– Muscle weakness

• Symptoms of toxicity:– Altered calcium

metabolism– Osteoporosis– UL = 4,000 mg

• Are supplements needed?

Major Mineral: Magnesium

• Functions:– Bone formation

– Blood clotting

– Regulation of blood pressure

– Enzyme activity

• RDA:– Men = 400 mg (19–30 yo)

to 420 mg (31–70 yo)

– Women = 310 mg (19–30 yo) to 320 mg (31–70 yo)

Source: USDA

Major Mineral: Magnesium (continued)

• Signs of deficiency:– Irritability– Muscle cramps– Heart arrhythmias– Hypertension

• Symptoms of toxicity:– Nausea, diarrhea,

vomiting– Muscle weakness– UL = 350 mg (from

supplements only)• Are supplements

needed?

Major Mineral: Sodium

• Functions:– Major electrolyte– Nerve impulse

transmission– Muscle contraction– Regulation of blood

pressure• RDA:

– 1,500 mgPhoto © Photodisc

Major Mineral: Sodium (continued)

• Signs of deficiency:– Hyponatremia– Nausea, vomiting– Seizures, coma

• Are supplements needed?

• Symptoms of toxicity:–Swelling–Increased blood pressure–UL = 2,300 mg

Major Mineral: Chloride

• Functions:– Major electrolyte– Nerve impulse

transmission– Aids digestion

(HCl)– Fluid balance

• AI:– 2,300 mg

Photo © Photodisc

Major Mineral: Chloride (continued)

• Signs of deficiency:– Increased blood pH– Abnormal heart

rhythm– Poor blood flow

• Symptoms of toxicity:– Increased blood

pressure– UL = 3,500 mg

• Are supplements needed?

Major Mineral: Potassium

• Functions:– Major electrolyte– Nerve impulse transmission– Muscle contraction– Blood pressure regulation

• RDA:– 4,700 mg

Photo © Digital Stock

Major Mineral: Potassium (continued)

• Signs of deficiency:– Muscle cramping– Muscle weakness– Loss of appetite– Heart arrhythmias

• Symptoms of toxicity:– Toxicity rare– UL not established

• Are supplements needed?

Photo © Digital Stock

Major Mineral: Sulfur

• Functions:– Part of hundreds of sulfur containing

compounds in the body

• No RDA, EAR, or AI has been established

Major Mineral: Sulfur (continued)

• Signs of deficiency:– Deficiencies rare– None that are

readily apparent

• Symptoms of toxicity:– Toxicity rare– Diarrhea and colitis– UL not established

• Are supplements needed?

Trace Mineral: Iron• Functions:

– Oxygen transport and utilization

– Component of hemoglobin and myoglobin

• RDA:– 18 mg (females aged

19 to 50)– 8 mg (all others) Source: USDA

Why are athletes at increased risk for iron deficiencies?

• Low dietary intake– Vegetarians beware

• Increased demand for hemoglobin and myoglobin due to training and sport

• Loss through sweat• Mechanical hemolysis

Trace Mineral: Iron

• Signs of deficiency:– Deficiencies

common– Anemia– Fatigue

• Symptoms of toxicity:– Nausea, diarrhea– Hemachromatosis– UL = 45 mg

• Are supplements needed?

Trace Mineral: Zinc• Functions:

– Cofactor in over 200 enzymatic systems• Wound healing• Growth and

maintenance• Protein synthesis• CNS, GI, and

reproductive systems• RDA:

– Men = 11 mg– Women = 8 mg

Source: USDA

Trace Mineral: Zinc (continued)

• Signs of deficiency:– Deficiency rare– Poor immunity– Dermatitis– Diarrhea– Loss of appetite

• Symptoms of toxicity:– Toxicity rare– Nausea and vomiting– Increased LDL– Anemia– UL = 40 mg

• Are supplements needed?

Trace Mineral: Chromium

• Functions:– Enhances function of insulin– Decreases cellular insulin resistance

• AI:– Men = 35 µg– Women = 25 µg

Trace Mineral: Chromium (continued)

• Signs of deficiency:– High blood sugar– Decreased muscle

endurance

• Symptoms of toxicity:– Toxicity rare– High levels may

decrease Zn and Fe absorption

– UL not established• Are supplements

needed?

Trace Mineral: Fluoride

• Functions:– Bone and tooth

mineralization– Prevents dental caries– Ligament/tendon

strength• AI:

– Men = 4 mg– Women = 3 mg

Trace Mineral: Fluoride (continued)

• Signs of deficiency:– Dental caries– Increased bone

fractures

• Symptoms of toxicity:– Toxicity rare– Fluorosis– Gastritis– Stiff joints– UL = 10 mg

• Are supplements needed?

Trace Mineral: Copper

• Functions:– Iron metabolism– Antioxidant

cofactor– Enzyme cofactor in

tissue growth and energy metabolism

• RDA:– 900 µg

Source: USDA

Trace Mineral: Copper (continued)

• Signs of deficiency:– Deficiency rare– Anemia– Bone and

connective tissue abnormalities

– Menkes Syndrome

• Symptoms of toxicity:– GI distress– Liver disease– Wilson’s Disease– UL = 10,000 µg

• Are supplements needed?

Trace Mineral: Manganese

• Functions:– Enzyme cofactor

• Metabolism• Antioxidant• Tissue growth

• AI:– Men = 2.3 mg– Women = 1.8 mg

Source: USDA

Trace Mineral: Manganese (continued)

• Signs of deficiency:– Poor growth– Bone and

connective tissue abnormalities

– Altered CHO and fat metabolism

• Symptoms of toxicity:– Fatigue, weakness– Neurological

problems– UL = 11 mg

• Are supplements needed?

Trace Mineral: Iodine

• Functions:– Assists in synthesis

of thyroid hormones

• RDA:– 150 µg

Source: USDA

Trace Mineral: Iodine (continued)

• Signs of deficiency:– Weight gain– Cold intolerance– Goiter

• Symptoms of toxicity:– Also can cause

goiter– UL = 1,100 µg

• Are supplements needed?

Trace Mineral: Molybdenum

• Functions:– Antioxidant cofactor– Enzyme cofactor in metabolism of amino

acids containing sulfur

• RDA:– 45 µg

Trace Mineral: Molybdenum (continued)

• Signs of deficiency:– Deficiency rare– Symptoms

unknown

• Symptoms of toxicity:– Toxicity rare– Symptoms unknown– Can decrease copper

absorption– UL = 2,000 µg

• Are supplements needed?

Trace Mineral: Selenium

• Functions:– Component of many

proteins in body– Enzyme cofactor

• Immune function• Thyroid function• Antioxidant

• RDA:– 55 µg

Source: USDA

Trace Mineral: Selenium (continued)

• Signs of deficiency:– Deficiency rare– Cardiomyopathy– Increased risk for

cancer

• Symptoms of toxicity:– Brittle hair and

nails– Hair and nail loss– UL = 400 µg

• Are supplements needed?

Other Trace Minerals