W8-L4: Major Minerals - Sodium Flashcards
What are the 5 functions of Sodium?
- Nerve Function
- Muscle Contraction
- Fluid Balance
- Transport of Molecules
- Blood Pressure Regulation
How does Sodium aid in Nerve Function?
Action Potentials: essential for generating action potentials in nerve cells, enabling the transmission of electrical signals throughout the nervous system
How does Sodium aid in Muscle Contraction?
Excitation-Contraction Coupling:
Na ions facilitate muscle contraction by allowing depolarization of muscle fibers,
How does Sodium aid in Fluid Balance?
Osmoregulation: helps regulate fluid balance in the body by controlling the movement of water in and out of cells, maintaining extracellular fluid volume
How does Sodium aid in
Transport of Molecules?
Sodium-Potassium Pump:
Sodium is crucial for the active transport of molecules across cell membranes, particularly through the sodium-potassium pump, which maintains cellular homeostasis
How does Sodium aid in
Blood Pressure Regulation?
Fluid Volume Control:
influences blood volume and pressure by affecting how much water is retained or excreted by the kidneys, impacting overall cardiovascular health.
What is the Adequate Intake for Sodium?
AI: 1,500mg/d
What is the UL for Sodium?
Remain below 2,300 mg/d for health
What is the Average Sodium
Consumption in Canada?
Average consumption in Canada is
~3,400 mg
Where are Canadians getting Sodium from?
- 77% processed foods
- 12% salt naturally found in food
- 6% saltshaker during meals
- 5% salt added to cooking
SODIUM RECOMMENDATIONS & CONFLICTING OPINIONS
When should Sodium intake be reduced?
Generally agreed that it is important to reduce sodium intake in those with hypertension
SODIUM RECOMMENDATIONS & CONFLICTING OPINIONS
What is the relationship b/w sodium & CVD?
- Controversy remains over the effects of sodium on other health outcomes, including CVD and mortality
- Some observational studies suggest a U-shaped or J-shaped curve, while others show a linear association with cardiovascular events and total mortality
What is the avg. Sodium loss during exercise?
Average sodium loss =
1,000mg (2.5g salt) per litre of sweat lost
Sodium loss in sweat can vary significantly among individuals due to factors like genetics, acclimatization to heat, and dietary sodium intake.
Why is Sodium crucial during exercise?
- Sodium helps maintain osmotic pressure, which is crucial for keeping fluid in the bloodstream and preventing dehydration during exercise or in hot conditions. (500mgs / L)
- Adequate sodium intake is vital for restoring electrolyte
balance after intense exercise, helping to prevent cramps and fatigue.
Example
Sweat & Sodium Loss over 4.5 hrs of practice
