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What is the daily requirement difference for minerals for major, trace, and ultratrace levels?

Major: >100 mg/day
Trace: <100 mg/day
Ultratrace: <1mg/day: i.e. Iodine, selenium (antioxidant), copper, chromium, molybdenum


How can zinc and protein status cause vitamin A deficiency?

Zinc -> metalloenzyme involved in conversion from retinol to retinal. It's also a component of Retinol binding protein, which is needed to hold onto vitamin A


How are calcium levels kept high in the blood over the lifespan? At what age do you start to lose bone?

Vitamin D, Parathyroid hormone work to increase blood calcium levels at the expensive of bone. Start to lose bone between 30-40 years old


What foods have the highest bioavailability of calcium? Calcium is the most abundant mineral in our body, making up 1-2% of our body weight

Cauliflower, watercress cabbage, and other leafy greens have >30% absorption.

Dairy products have generally only about ~30% absorption, but you need to eat alot


What greens are surprisingly low in calcium bioavailability? Why?

~5% of spinach, rhubarb, and swiss chard is absorbed. Even almonds and legumes are around 20% absorption

This is because phytanic acid in whole grains, seeds, and legumes inhibit absorption

Oxalic acid in greens inhibits absorption


What factors affect calcium bioavailability in the stomach?

Gastric acidity -> proton pump inhibitors (i.e. omeprazole) will increase fracture risk


What dietary factors affect calcium absorption?

Lactose, sugars, and protein all improve absorption, while fiber inhibits absorption


What is the effect of high levels of zinc and magnesium in the food on calcium absorption?

Decreases it, as they compete at the brush border as other divalent cations


What affect to unabsorbed fatty acids have on fat soluble vitamin absorption?

Decrease it, by forming soaps.


What type of minerals are zinc and iron? Calcium?

Iron and zinc are trace minerals, while calcium is considered a major mineral (greater than 100 mg / day)


What is the most common mineral deficiency worldwide, and what is its more absorbable form?

Iron deficiency
Ferrous - more absorbable +2
Ferric - less absorbable +3


What is more available, heme or nonheme iron?

Heme iron is about 5x more absorbable


What factors enhance the absorption of iron?

MFP - meat fish poultry factor
Vitamin C
Sugars / acids


What factors inhibit the absorption of iron?

Phytates - compete at the border
Polyphenols, vegetable proteins, and divalent cations like calcium


What is the function of ferritin?

Protein that stores iron, particularly around the small intestine


What is the function of transferrin? What stage of iron deficiency is this?

The transporter of iron. In the second stage of iron deficiency, the concentration of this transporter increases


What groups are at-risk for iron deficiencies?

1. Pregnant women, who need 50% more iron -> need to prevent low birth weight / low iron stores
2. adolescent women -> prevent psychiatric disorders
3. infancy / young children -> need to prevent learning disorders / autism


What inhibits zinc absorption?



What are the risk factors for vitamin A deficiency?

Low fat intake, fat malabsorption, low retinol binding protien due to impaired protein status (RBP), low zinc (need zinc for storage)


What are the risks of vitamin A deficiency?

1. Xerophthalmia - excess eye dryness which can lead to blindness
2. Keratinization / hyperkeratosis
3. Infectious disease -> due to immune function
4. Skin problems, especially regarding epithelial cells (dry scaly skin, weakened respiratory and urinary tract defenses, vagina)
5. Anemia


What are the risks of vitamin A toxicity? Beta-carotenes?

Teratogen -> craniofacial, heart, CNS, miscarriage

Bone defects -> interferes with vitamin D, may cause osteoporosis

Beta-carotene precursor is an antioxidant which may become pro-oxidant


What are the child and adult manifestations of vitamin D deficiency?

Child: Rickets, bendy bones which don't calcify
Adult: Osteomalacia, soft flexible deformable bones


Who are the high risk groups for vitamin D deficiency?

Elderly: With low sun exposure and low dietary intake, decline in synthesis / kidney activation
Post-menopausal women: interferes with intestinal absorption
Pregnancy: low levels can lead to low infant body weight


What is the potential toxicity of vitamin D?

Highest likelihood of toxicity: Hypercalcemia with anorexia, nausea, weakness, kidney stones, calcium deposits in soft tissue (heart / lung), hypertension, and deposition in blood vessels


What are the symptoms of vitamin E deficiency?

1. Hemolytic anemia - oxidative damage
2. Weakness, ataxia, peripheral neuropathy
Secondary genetic deficiencies can lead to growth defects in infants (abetalipoproteinemia)


What is the potential toxicity of vitamin E?

GI distress, interferes with vitamin K and leads to hemorrhage (too much anticoagulation)


What are the symptoms of vitamin K deficiency?

Fatal anemia from primary deficiency, which is rare.
Secondary deficiency: brusing, petechiae, stomach pain, bone malformation


What can cause vitamin K deficiency / high risk groups?

Fat malabsorptive diseases as in IBD, liver disease, cystic fibrosis
Antibiotics like cephalosporine, anticoagulants, aspirin, anticonvulsants


What are the possible problems with vitamin K excess?

There is no UL, however, if you are on anticoagulants, you must be consistent in vitamin K intake. Half comes from diet, half comes from microbes


What are the signs of vitamin C deficiency?

4 H's - Scurvy
1. Hemorrhagic signs
2. Hyperkeratosis of hair follicles
3. Hypochondriasis (psychological)
4. Hematologic abnormalities