Water and Electrolyte Balance in the Human Body - 12

Body Water Percentage

Water constitutes 60% of adult body weight.

Children's Water Percentage

Higher body water percentage compared to adults.

Gender and Age Impact

Females and elderly have lower body water percentage.

Obesity and Water

Obese individuals have a lower percentage of body water.

Muscle and Water Content

More muscle correlates with higher body water percentage.

Water Functions

Carries waste, nutrients, and maintains molecular structure.

Water as Lubricant

Acts as lubricant in joints and organs.

Spinal Cord Fluid

Protects spinal cord and cushions it.

Fetal Protection Fluid

Fluid that safeguards the developing fetus.

Body Temperature Regulation

Maintains temperature via perspiration.

Blood Volume Influence

Affects blood pressure and circulation.

Intracellular Fluid

Fluid within cells, making up 2/3 of total.

Extracellular Fluid

Fluid outside cells, comprising 1/3 of total.

Interstitial Fluid

Fluid surrounding cells, part of extracellular fluid.

Intravascular Fluid

Fluid contained within blood vessels.

Electrolytes

Salts that dissociate into ions in water.

Cations

Positively charged ions in body fluids.

Anions

Negatively charged ions in body fluids.

Electrolyte Balance

Equal electrolytes inside and outside cells.

Water Attraction

Electrolytes and proteins attract water molecules.

ADH Function

Regulates water reabsorption in kidneys during dehydration.

Renin Role

Enzyme that promotes sodium reabsorption and water retention.

Angiotensin II

Active form that constricts blood vessels to raise pressure.

Aldosterone Function

Signals kidneys to retain sodium and excrete potassium.

Oral Rehydration Therapy (ORT)

Solution of sugar, salt, and water for rehydration.

pH Regulation

Ions regulate body acidity to prevent protein denaturation.

Buffers in Blood

Bicarbonate and carbonic acid neutralize acids and bases.

Carbonic Acid Formation

Carbon dioxide in water forms carbonic acid.

Kidney Bicarbonate Management

Regulates bicarbonate levels through reabsorption or excretion.

Daily Water Excretion

Body must excrete 2 cups of water daily.

Thirst Mechanism

Hypothalamus and nerves detect hydration status.

Thirst response

Lagging reaction to body's water needs.

Dehydration symptoms

Signs include fatigue, dizziness, and dry mouth.

Water intoxication

Excessive water intake causing confusion and convulsions.

Excess water intake

Drinking 10-20 liters in hours causes intoxication.

Fluid intake sources

All fluids contribute, except high salt/sugar drinks.

Adequate Intake (AI) for water

Recommended 2-3 liters (8-12 cups) daily.

Diuretic effect of coffee

Coffee mildly increases urine production.

Hard water

Contains more calcium and magnesium than soft water.

Soft water

Contains more sodium or potassium than hard water.

Major minerals

Needed in large amounts for body functions.

Trace minerals

Required in small amounts for health.

Sodium functions

Regulates fluid volume, nerve impulses, and muscle contraction.

Sodium intake recommendation

1500 mg daily, less than a teaspoon of salt.

Sodium deficiency

Rare, usually due to illness causing sodium loss.

DASH diet

Encourages potassium-rich foods, limits sodium intake.

Chloride functions

Maintains fluid balance and is part of HCl.

Chloride intake recommendation

2300 mg daily for adults, higher for older adults.

Potassium functions

Maintains cell structure and electrolyte balance.

Potassium intake recommendation

3400 mg for men, 2400 mg for women.

Potassium deficiency effects

Can lead to high blood pressure and kidney stones.

Potassium toxicity

Caused by excessive supplements, not food.

MSG (Monosodium glutamate)

Flavor enhancer that occurs naturally in foods.

Sodium nitrate

Preservative found in processed meats like cold cuts.

Potassium toxicity

Excess potassium from consumption can be harmful.

Kidney function

Kidneys increase excretion to manage potassium levels.

Calcium

Most abundant mineral, crucial for bone health.

Calcium bank

Bones release calcium to maintain blood levels.

Extracellular calcium

Vital for blood clotting and muscle function.

Intracellular calcium

Regulates muscle contractions and nerve impulses.

Parathyroid hormone

Released to increase blood calcium when low.

Calcitonin

Hormone that lowers blood calcium levels.

Calcium rigor

High calcium causes muscles to contract without relaxing.

Tetany

Low calcium leads to muscle spasms.

Calcium absorption

Adults absorb about 30% of dietary calcium.

Calcium recommendations

1300mg/day for adolescents, 1000mg/day for adults.

Osteopenia

Bone density loss due to low calcium intake.

Phosphorus

Second most abundant mineral, essential for DNA.

Hydroxyapatite crystals

Formed from calcium and phosphorus in bones.

Phosphate

Key component of ATP and buffer systems.

Phosphorus toxicity

Rare; indicates underlying health issues.

Magnesium

Essential for bone health and energy metabolism.

Magnesium sources

Found in nuts, seeds, legumes, and greens.

Magnesium deficiency

Rare, but can cause severe health issues.

Sulfate

Oxidized sulfur, found in various foods.

Hyponatremia

Condition of low sodium levels in blood.