Water and Major minerals Flashcards
What percentage of an adult’s body is water?
About 55%.
Lean individuals have a higher percentage due to more muscle mass and glycogen.
Where is water found in the body?
2/3 is intracellular, and 1/3 is extracellular (interstitial fluid and blood).
What controls water movement between body compartments?
Solute concentrations, managed by osmosis and cell membrane pumps like the sodium-potassium pump.
What are the functions of water in the body?
Maintains blood volume, transports nutrients, regulates temperature, supports chemical reactions, and produces fluids like urine and saliva.
How much urine is typically produced daily?
Between 4.5 to 8.5 cups per day.
What are dietary sources of water?
Water, fruits, vegetables, non-alcoholic beverages.
What is the AI for water intake?
10–15 cups per day (2800 mL), varies by body size, activity, and environment.
How does the body regulate water balance with minor changes?
Hypothalamus signals ADH release, which causes kidneys to retain water, increasing blood volume.
What is the renin-angiotensin system’s role in water balance?
Renin converts angiotensinogen to angiotensin I, which becomes angiotensin II, causing vasoconstriction and aldosterone release, increasing sodium and water retention.
What does aldosterone do?
Increases sodium retention in kidneys, leading to water retention and higher blood pressure.
What causes dehydration?
Diarrhea, vomiting, fever, sweating, burns, excessive urination, uncontrolled diabetes
What are the symptoms of dehydration
Dry mouth, thirst, low or dark urine, headaches, dizziness, fainting, coma, death
What causes water intoxication?
Drinking excess water without electrolytes, especially during exercise or with kidney failure.
What is hyponatremia?
Low sodium concentration caused by dehydration, potentially leading to coma or death.
What distinguishes major and trace minerals?
Major: need >100 mg/day; Trace: need <20 mg/day.
What affects mineral bioavailability?
Source (animal better than plant), need, amount consumed, and other dietary components.
What is the primary way minerals are excreted?
Through urine. Kidney failure can reduce excretion and cause toxicity.
What are the most common major mineral deficiencies in the U.S.?
Calcium, potassium, and magnesium.
What are the most common trace mineral deficiencies?
Iron, zinc, and iodine.
What are food sources of sodium?
Table salt, processed foods, canned foods, restaurant meals, salted snacks.
What are the functions of sodium?
Electrolyte balance (main extracellular cation), nerve/muscle function, glucose absorption, preservative.
What is the AI and UL for sodium?
AI: 1500 mg/day; UL: 2500 mg/day.
What are the effects of sodium deficiency and toxicity?
Deficiency is rare (hyponatremia). Toxicity may cause hypertension or stomach cancer.
How much sodium is in 1 tsp of salt?
About 2300 mg.
