Magnesium

Question 1

Food sources

Answer 1

Whole Grain
Legumes
Nuts 
Green leafy vegetables
Tofu 
Chocolate
Water
Intermediate
meats
Fruits

Question 2

People who have cravings such as chocolate may be deficient in what?

Answer 2

Magnesium

Question 3

What is hard water and soft water?

Answer 3

Hard water is high in magnesium

Soft water is high sodium

Question 4

Where does magnesium absorption mainly occur?

Answer 4

In the small intestine

~40-60% absorbed

Question 5

How is magnesium absorbed in the intestine?

Answer 5

By passive diffusion or active transport
In small intestine = paracellular diffusion
Large intestine = TRPM6 (main) and TRPM7 (a little)Ho

Question 6

Substances that enhance absorption of magnesium

Answer 6

Vitamin D
Carbohydrates
-Lactose
-Fructose

Question 7

Substances that inhibit absorption

Answer 7

Phytate
Fiber
Excess unabsorbed fatty acids

Question 8

Magnesium interacts with which nutrients?

Answer 8

Calcium
phosphorus
Potassium
Protein

Question 9

How is magnesium transported?

Answer 9

55% free as mg2+
30% bound to albumin
15% complexed with citrate, sulfate, phosphate

Question 10

Serum mg ranges

Answer 10

1.8-2.3mg/dl

Question 11

Does Mg have a specific transporter?

Answer 11

No, similar to calcium

Question 12

Magnesium is regulated how?

Answer 12

It is regulated by the amount you excrete which is regulated by the kidneys
high excretion = high intake
low excretion = low intake

Question 13

How does alcohol effect urinary Mg?

Answer 13

It increases it. More excretion.

Question 14

Where is magnesium stored in the body?

Answer 14

Most of it is found in the skeleton (bones)

Question 15

What are the functions of Mg?

Answer 15

Important intracellular cation
Ionized Mg2+ binds well to anions
Stabilize enzyme complexes

Question 16

Most intracellular Mg is associated with what?

Answer 16

ATP, ADP, and associated enzymes

Question 17

Mg-ATP is used in

Answer 17

Glucose metabolism
Energy storage and transfer
Signaling pathways
Ion transport
Lipid metabolism

Question 18

What does Mg do to RNA and DNA

Answer 18

Stabilizes it because the negatively charged ribose phosphate has high affinity for Mg

Question 19

Mg reacting with the hydrophilic phosphate heads of cell membranes affects what? What does this influence?

Answer 19

Affects the fluidity and permeability of the cell membrane

This influences ion channels, transporters, and signal transducers

Question 20

Disruption of the Na K ATPase by Mg depletion may lead to what?

Answer 20

Hypokalemia (low blood potassium)

Question 21

What is the Magnesium-Calcium interaction?

Answer 21

Mg is required for c-AMP formation because it is dependent on Mg
cAMP is required for PTH secretion

Question 22

What are the functions of PTH?

Answer 22

Bone calcium mobilization

Kidney calcium resorption

Question 23

What signals PTH to be secreted?

Answer 23

Low blood calcium

Question 24

The deficiency of Mg can inhibit the secretion of which hormone?

Answer 24

PTH

Question 25

Mg deficiency is related to osteoclasts how?

Answer 25

Osteoclasts become unresponsive to PTH in Mg deficiency - Bone remodeling is reduced - blood ca decreases

Question 26

Mg Assessment

Answer 26

Plasma Mg poor indicator because it is maintained in a very tight range anything below 1.8 indicated Mg depletion

Question 27

How can Mg deficiency occur?

Answer 27

Not by diet | Mutation in TRPM6

Question 28

Mutation of TRPM6 leads to what?

Answer 28

Familial hypomagnesemia and hypocalcemia, seizures, and tetany

Question 29

Can you get enough Mg without the TRPM6 protein?

Answer 29

No. It does not absorb much but what its enough to not be deficient. Removing this will cause there to be a deficiency

Question 30

In animals, Mg deficiency causes and can they be reversed?

Answer 30

- Low plasma Mg - Hypocalcemia - Hypokalemia - Abnormal neuromuscular function - low PTH - Low 1,25(OH)D3 (Calcitriol) Yes they can be reversed

Question 31

Severe Mg deficiency causes what?

Answer 31

Tetany (all muscles are locked up) convulsions neuromuscular tremors

Question 32

Clinical Mg Deficiency

Answer 32

- Surgery - Blood transfusions: citrate chelating (citrate can bind to Ca and Mg. Ca is important for blood clotting. if you have a bag of blood stored, you do not want blood to clot. They add a lot of citrate to prevent all of the clotting factors. With so much citrate in the blood, the citrate will also bind to a lot of the Mg and render a state of Mg deficiency and that Mg is no longer metabolically active because it has been chelated to Citrate" - diabetic ketoacidosis - alcoholics - chronic malabsorptive problems

Question 33

Suboptimal Mg status has been associated with?

Answer 33

Cardiovascular and neuromuscular disease diabetes osteoporosis migraines

Question 34

The UL for Mg represent what?

Answer 34

Pharmacological agents only. | They do not include intake from food and water

Question 35

Mg toxicity

Answer 35

Adverse effects only with supps -primarily diarhhea (Mg supps can help with constipation) -cathartic effect (vomiting) Can not get toxic from food