Lesson 8: Minerals Flashcards
Where do minerals come from? Can we synthesize minerals?
Minerals come from the earth. No living organism can synthesize minerals.
What are the 7 major minerals?
Sodium Magnesium Potassium Calcium Phosphorus Sulfur Chlorine
What are the 8 trace minerals?
Fluorine Chromium Manganese Iron Copper Zinc Selenium Iodine
What % of the elements on earth are required by the human body?
25%
Which is the most abundant trace mineral?
Iron
What do we call the fluid within cells?
Intracellular fluid
What is the intracellular fluid usually rich in?
Potassium and phosphate
What do we call the fluid that is outside of a cell?
Extracellular fluid
What do we call the fluid between cells?
Interstitial/Intercellular fluid
What is interstitial fluid rich in?
Sodium chloride
Where is intravascular fluid found?
inside blood vessels
What is our principle source of minerals?
Food
What is the difference between hard water and soft water?
Hard water has a high concentration of calcium and magnesium. It can taste and smell unpleasant. Soft water is treated with sodium or potassium. Soft water can help extend the life of plumbing and washing machines.
What does the bioavailability of minerals depend on?
Your body’s physiological need for it at the time of consumption. Mostly dictated by gender, age and diet.
What can affect bioavailability?
Source of minerals
Combination of foods you eat
Presence of other minerals due to their chemical nature
What are binding factors?
Compounds that bind to minerals, preventing their absorption
Plants contain compounds called ______ and _______ that can combine with minerals in the small intestine and make them unavailable for absorption.
Phytates
Oxylates
What is calcium stored in bones as?
Hydroxyapatite crystals
Where does it form?
On the foundation of collagen
What does calcium in bones also act as?
a reservoir for when blood calcium levels drop
Calcium contributes to __________ and ___________.
bone health and neural communication
Where is <1% of blood calcium found?
In the intravascular and interstitial compartments
What is the synaptic cleft?
the space between the pre-synaptic and post-synaptic cells
What happens in the synaptic cleft as the electrical signal travels toward the end of the presynaptic neuron?
tiny protein channels embedded in the plasma membrane open up
What happens as the tiny protein channels open?
Calcium floods into the presynaptic neuron
Once inside the presynaptic neuron, what happens?
the calcium allows the tiny vesicles carrying neurotransmitters to spill into the synaptic cleft.
Once in the synaptic cleft, what happens?
an electrical signal is generated and runs down the next neuron
What happens to neurotransmitters without calcium?
the neurotransmitters are not released and neurons fail to communicate
What do osteoclasts do?
Degrade bone tissue to release calcium (breakdown bone during growth)
What do osteoblasts do?
build bone tissue (build new bone during growth)
What is the activity of osteoclasts and osteoblasts regulated by?
The thyroid and parathyroid glands
Which gland is butterfly shaped and wraps itself around the trachea?
Thyroid gland
What does the thyroid gland do?
Helps regulate blood calcium levels by controlling activity of osteoblasts and osteoclasts.
Which gland is composed of 4 smaller glands located behind the thyroid gland?
Parathyroid gland
What does the parathyroid gland do?
Synthesizes hormones that are released into the blood. & Helps regulate blood calcium levels by controlling activity of osteoblasts and osteoclasts.
When calcium blood levels fall, how does the parathyroid gland produce and secrete PTH?
PTH stimulated by activation of vitamin D in kidneys.
PTH-Vitamin D duo increase calcium reabsorption in kidneys
Vitamin D travels to the small intestine and increases bioavailability of calcium
PTH-Vitamin D duo stimulates osteoclasts to break down bone
Which food has the highest bioavailability for calcium?
a single serving of milk
Where does calcium go after being absorbed from the small intestine?
Enters the circulatory system
What happens if blood calcium levels are low?
The PTH/Vitamin D complex force kidney to reabsorb calcium out of the urine
What is another nutrient that can alter calcium homeostasis?
Sodium. Excess sodium intake forces kidneys to increase urine production in an effort to eliminate excess sodium and calcium is also lost.
What is peak bone mass?
highest attainable bone density achieved in the first 3 decades of an individual’s life
Regardless of gender, when does bone density begin to drop?
after age 30
____________ is a hormone that decreases osteoclast activity?
Estrogen
What happens after menopause?
Increased osteoclast activity
What is osteoporosis?
disease of severely low bone density
What are 2 ways to minimize osteoporosis?
Maximize peak bone mass in early adulthood
Resistance exercise well into older age to put osteoblasts to work
Meet the RDA for calcium
What percentage of phosphorus is stored in bones?
85%
What percentage of phosphorus is found in the intracellular fluid compartments?
15%
Why is it nearly impossible to be deficient in phosphorus?
It’s in nearly everything we eat.
What can happen if you consume too much calcium and too much phosphorus?
It can cause calcium to leech out of teeth causing severe tooth decay
Where is 50% of magnesium found? What does it influence?
In bones. It influences the formation of hydroxyapatite crystals.
Mg in plants is found associated with what?
The green pigment chlorophyll
What roles does sodium play?
Fluid balance
Neural communication
Where is most of the sodium in the body found?
in intravascular and interstitial compartments
How does sodium aid in neural communication?
When neurotransmitters bind to ion channels on postsynaptic membrane, sodium floods into the postsynaptic cell. The influx of sodium allows nerve impulses to be propagated.
Sodium is crucial in controlling volume of the extracellular fluid compartments because where ions go, ________.
Water flows
What is high sodium intake associated with?
Hypertension
What is hypertension?
chronically elevated blood pressure and CVD
What is high blood pressure a sign of?
That the heart & blood vessels are being overworked
What happens if someone has persistently high blood pressure?
It places greater stress on heart to pump blood through stiff arteries
Muscle tissue of enlarged heart is very thick (heart overworking)
Enlarged heart is not desirable and can lead to heart failure
What is the UL for sodium?
2300 mg/day
What is the AI for sodium?
1500 mg/day
How many mg per day do most Canadians and Americans consume?
3400 mg/day
What is potassium crucial for?
Fluid Balance and Neural Communication
Is potassium found in a large variety of foods?
Yes
What is potassium associated with?
Lowering blood pressure
What is a natural way to counteract high sodium intake?
Consume food naturally high in potassium and low in sodium, like fruits
Oxygen enters inside RBCs and binds to iron. What happens to oxygen without iron?
It has nowhere to bind
Epithelial cells of the small intestine produce an iron-storage protein that binds to iron, preventing it from entering into the bloodstream. What is this protein called?
Ferritin
Is iron bound to ferritin available or unavailable for absorption?
Unavailable
What happens during a state of iron abundance?
Large amounts of ferritin are made that bind to iron in epithelial cells, preventing it from entering blood capillaries.
What happens during a state of iron deficiency?
low amounts of ferritin are synthesized
Absence of ferritin allows iron to be absorbed into epithelial cells, exit from the other end and enter in the blood capillaries
What does the bioavailability of iron depend on?
the bodys physiological need for it and the source of iron consumed (being heme or nonheme)
Which foods contain heme iron (but also nonheme iron)?
Animal food sources
Which foods only contain nonheme iron?
Plants
Which is better absorbed? Heme or nonheme?
Nonheme accounts for 90% of the daily intake, but heme, which accounts for 10% is BETTER absorbed than nonheme.
What is iron-deficient anemia?
severe depletion of iron stores that results in low hemoglobin concentration and small, pale red blood cells
What do we call anemia that impairs hemoglobin synthesis?
microcytic
What are high-risk groups for iron-deficient anemia?
Women (menstrual blood loss)
pregnant women
growing infants
children and teens
Upon absorption, where does almost all iodide end up?
In the thyroid gland
What is iodide’s singular function?
the synthesis of thyroid hormones
What is the world’s major source of iodide?
The ocean
Where is a rich supply of iodide found?
In soils that were once submerged by ancient seas
What is iodide deficiency the leading cause of globally?
Mental impairment
What is Goiter?
deficiency disease of iodide resulting from an enlarged thyroid gland
What is Cretinism?
Deficiency disease affecting the developing fetus of pregnant women. There is impaired fetal development, stunted growth and physical and mental abnormalities
What does chromium do?
It enhances the ability of insulin to take glucose into your cells
What are the many functions of zinc?
Energy Metabolism Amino acid metabolism DNA metabolism Antioxidant function Heme synthesis Growth and Development Required as a cofactor by >100 enzymes
What does a deficiency in zinc cause?
Severely impairs growth and development
Zinc, Copper and Selenium all have ________ function.
Antioxidant
Which mineral is very rich in Brazilian nuts and acts as an antioxidant?
Selenium
Where does fluoride get deposited?
in hydroxyapatite crystal in teeth to form fluorapatite
What does fluoridated water do?
decreases rates of tooth decay by promoting formation of fluorapatite
What is a symptom of fluoride toxicity?
fluorosis (motheling of teeth)
