Nutrition module 9

Fluoride is incorporated into fluorapatite crystals which strengthens tooth enamel (T/F)

True

Generally, as sodium intake goes up blood pressure goes up (T/F)

True

Most loss of iron from the body is associated with blood loss (T/F)

True

After 35 to 45 years of age a) bone breakdown exceeds bone formation b) skeleton is typically weak and fractures easily c) bone formation is equal to bone breakdown d) bone formation exceeds bone breakdown

a) bone breakdown exceeds bone formation

Iodine deficiency often causes an enlarged thyroid gland, resulting in a) blockage of arteries leading to the heart b) a goiter c) a dowager's hump d) shortness of breath

b) a goiter

Phosphoric acid in colas may be detrimental to a) blood clotting due to effects on vitamin B12 b) bone health due to effects on vitamin D activation c) liver function due to effects on protein metabolism d) blood vessel health due to effects on vitamin C recycling

b) bone health due to effects on vitamin D activation

Most of the fluoride in the US comes from a) dark green and yellow vegetables b) drinking water and toothpaste c) tea d) seafood and treated salt

b) drinking water and toothpaste

Drinking plain water after a long period of excessive sweating can do all of the following EXCEPT a) dilute the sodium in the blood b) increase potassium in the blood causing high blood pressure c) cause water toxicity d) result in nausea, muscle cramps and confusion

b) increase potassium in the blood causing high blood pressure

The RDA for iron is increased in vegetarians compared to omnivores due to a) increased iron absorption due to defects in hepcidin regulation b) nonheme iron having lower bioavailability than heme iron c) increased turnover of red blood cells due to foot strike hemolysis d) heme iron having lower bioavailability than nonheme iron

b) nonheme iron having lower bioavailability than heme iron

Zinc deficiency in young men (associated with growth depression and delayed sexual development) occurred because a) the diet was low in zinc since local soils were low in zinc b) phytates in the diet bound zinc, decreasing its bioavailability c) they consumed diets high in animal protein, which inhibits zinc absorption d) they did not eat meat

b) phytates in the diet bound zinc, decreasing its bioavailability

Good sources of magnesium include all of the following EXCEPT a) leafy green vegetables b) processed foods c) whole grains d) nuts

b) processed foods

Magnesium's major functions in the body include all of the following except: a) maintenance of bones b) transporting oxygen in the blood as a component of chlorophyll c) being a cofactor for many enzymes involved in macronutrient metabolism d) stabilizing ATP

b) transporting oxygen in the blood as a component of chlorophyll

Which mineral is found in varying amounts in food depending on where it is grown? a) zinc b) magnesium c) iodine d) calcium

c) iodine

Excess fluoride consumption as a child may cause fluorosis, a condition where a person has a) spontaneous dental hydroplosion b) hives and dermatitis c) stained, pitted teeth d) arthritis

c) stained, pitted teeth

Discuss who is at greater risk for dehydration

o Athletes (lost as sweat) o Older adults (thirst mechanism impaired) o Infants (high evaporation losses, immature kidneys) Conditions associated with diarrhea (fecal water losses

· Why do vegetarians need greater amounts of iron?

o Because the iron they get from veggies and fruits isn't absorbed as easily compared to meats

· What is hemochromatosis? How does too much iron in the body cause damage?

o Causes increased iron absorption. A defect in hepcidin gene regulation. Low iron diet and blood letting In children - leading cause of liver transplants. It reacts with oxygen to form free radicals

· How might phosphoric acid levels of colas in negatively impact bone health?

o Colas have no calcium and high phosphorus. High blood phosphorus levels inhibit vitamin D activation. This is associated with a higher risk of osteoporosis.

Discuss three dietary factors that affect iron absorption

o Enhancing factors - ascorbic acid and meat, fish and poultry o Inhibit factors - plant components in veggies, tea and coffee (phytates, tannins) and calcium

· What contributes most to fluoride consumption for Americans?

o Fluoridated water, tea, marine fish (with bones), Teflon utensils, fluoride toothpaste

· What can happen to the teeth of children if they get too much fluoride?

o Fluorosis - can happen from large amounts in drinking water and if children swallow large amounts of toothpaste. § Will cause teeth to appear mottled

· What is the relationship between dietary sodium and blood pressure?

o Generally, as sodium intake increases, blood pressure increases

· Explain the differences between heme iron and nonheme iron.

o Heme iron is iron from animal products and its bioavailability is not affected by other foods Nonheme iron is from plant products (leafy greens), cookware, supplements, and is not absorbed well. Their bioavailability has positive and negative factors. They are improved by stomach acid, other acids, and meat. Reduced by fiber, phytates, tannins, and xalates

· What disorders/conditions can iodine deficiency cause in adults and children?

o Hypothyroidism - BMR slows, weight gain o Reduced production of thyroid hormones o Goiter (big thyroid) o Cretinism (birth defect due to low iron in pregnancy), mental disabilities caused

· How does fluoride strengthen tooth enamel? What is a common dental problem associated with not getting enough fluoride?

o Incorporated into tooth enamel and bones o Hydrozyapatite crystals - fluorapatite - remineralization o Increased resistance to acids o Topical fluoride beneficial

· Which trace mineral is a component of hemoglobin? Why is hemoglobin important in the body?

o Iron o Hemoglobin in the RBCs carry oxygen to the body's organs and tissues and transports carbon dioxide back to your lungs

· What are the functions of magnesium in the body?

o Magnesium is a cofactor in more than 300 enzyme systems that regulate protein synthesis, muscle and nerve function, blood glucose level, and blood pressure regulation o Required for energy production, oxidative phosphorylation and glycolysis

· Explain the difference between major minerals and trace minerals.

o Major minerals are needed in the diet >100 mg/day or present in body >0.01% of body weight (calcium) o trace minerals are needed in the diet <100 mg/day or present in body <0.01% of body weight (iron)

· At what age range does bone breakdown usually start to exceed bone formation?

o Men and women start to lose bone mass slowly at 35 o More bone loss by women above 51 and men above 70

· What is the major route of iron loss from our body?

o Most loss from bleeding

· What are the primary dietary sources of magnesium?

o Nuts, seeds, leafy greens, bananas, whole grains

· Are all forms of salt in the diet fortified with iodine? How about salt from processed foods?

o Only fortified salt. Natural sea salt may be very low in iodine o Processed foods contain non-iodized salt

· What dietary compounds can reduce mineral absorption?

o Phytates In whole grains, seeds, legumes, some nuts can decrease the absorption of iron, zinc, mg, and calcium o Tannins in tea and coffee can decrease iron absorption o Low protein diet

· What are the functions of phosphorus in the body?

o Provides phytate, phospholipids o 85% found in bones and teeth o Body uses phosphorus to repair bones and teeth, help nerves function, and make muscles contract o As a phosphate, it is required by every cell

List the 3 principal electrolytes in body fluids

o Sodium, potassium, chloride

· Why is sodium added to foods?

o Some is added as table salt but majority is added through processing. It is added to control microbial growth, for taste and texture, fermentation

· Describe the symptoms of dehydration and overhydration/water intoxication.

o Symptoms of dehydration § 1-2% of body weight - headache, fatigue, dark-colored urine § 5% - nausea and difficulty concentrating § 7% - confusion and disorientation § 10-20% - fatal o Symptoms of overhydration Nausea, vomiting, clear urine, headache, confusion and disorientation

· What types of foods contribute the most sodium to the North American diet?

o Table salt (NaCl) o Processed foods

· Describe the DASH diet, and how it affects blood pressure?

o The DASH diet emphasizes veggies, fruits, and low-dairy foods. It moderates amounts of whole grains, fish, poultry and nuts. A low sodium diet o It is effective in reduction blood pressure

· How is calcium intake related to the risk of osteoporosis?

o With low calcium in diet mean higher risk of osteoporosis

· What is the primary role of iodine in the body?

o ~75% of iodine is found in thyroid o Essential component of thyroid hormones § Thyroxine (T4) found in blood § Triiodothyronine (T3) active form o Gene expression and protein synthesis o Regulated basal metabolic rate, growth and development

· Are trace elements/minerals as important as major minerals in the body?

yes

The primary role of iodine in the body is: A. as an antioxidant. B. as a cofactor in hemoglobin synthesis. C. participation in carbohydrate metabolism D. as a component of thyroid hormones.

D. as a component of thyroid hormones.

· If dietary calcium is low, how is blood calcium concentration maintained?

The equilibrium of calcium is maintained by calcium absorbed in the intestines, the movement of calcium in and out of the bones, and the kidney's reclamation and excretion of calcium into the urine

Whether an element is classified as a major or as a trace mineral is determined by a) where they are found on the periodic table b) where they are absorbed in the digestive tract c) the amounts needed daily by the body d) how critical they are for metabolic processes

c) the amounts needed daily by the body

Which of the following individuals is a risk for dehydration? a) an athlete, exercising in cool weather b) an elderly woman, just returning from a 4 hour flight c) a child recovering from diarrhea d) all are potentially at risk for dehydration

d) all are potentially at risk for dehydration

Fluoride has shown to be most effective in preventing a) colon cancer b) obesity c) osteomalacia d) dental caries

d) dental caries

Which of the following is NOT likely to result from prolonged low calcium intake a) fractures in the elderly b) a lower peak bone mass in young adult females c) development of osteomalacia d) problems with cell signaling and regulation

d) problems with cell signaling and regulation

most of the salt consumed by Americans is: a. found naturally in food b. added during home preparation c. added at the table d. added to food during processing and manufacturing

d. added to food during processing and manufacturing

· Which mineral is found in varying amounts in food depending on where it is grown?

iodine