Nutrients Involved in Fluid and Electrolyte Balance

Intracellular and Extracellular Electrolytes

Electrolytes are minerals that carry an electric charge and are essential for various physiological functions. They are distributed in the body as intracellular (inside cells) and extracellular (outside cells) electrolytes.

• Intracellular Electrolytes: Potassium (K+) and Phosphate (PO43-) are the primary electrolytes inside cells.

• Extracellular Electrolytes: Sodium (Na+) and Chloride (Cl-) are the main electrolytes outside cells.

• Water Movement: Water moves across cell membranes by osmosis, following the concentration of electrolytes. Changes in electrolyte concentration can cause cells to shrink or swell.

Example: High extracellular sodium causes water to move out of cells, leading to cell shrinkage.

Major Functions of Electrolytes

• Regulate fluid balance between compartments

• Enable nerve impulse transmission

• Support muscle contraction

• Maintain acid-base balance

Factors Affecting Body Water Percentage

• Age (decreases with age)

• Gender (males typically have higher water content)

• Body composition (more muscle = more water)

Definitions: Dehydration, Heat Stroke, Heat Cramps, Heat Exhaustion

• Dehydration: Excessive loss of body water, leading to impaired function.

• Heat Cramps: Muscle spasms due to electrolyte loss during intense activity in heat.

• Heat Exhaustion: Heavy sweating, weakness, and rapid pulse from prolonged heat exposure.

• Heat Stroke: Life-threatening failure of the body's heat-regulating mechanisms; body temperature rises dangerously high.

Thirst Mechanism

• Controlled by the hypothalamus in response to increased blood osmolality or decreased blood volume.

• Stimulates desire to drink before dehydration occurs.

Function of Water in the Body and Sweating

• Solvent for biochemical reactions

• Transports nutrients and waste

• Regulates body temperature via sweating

• Lubricates joints and tissues

High/Low Sodium Foods

• High Sodium: Processed foods, canned soups, deli meats, snack foods

• Low Sodium: Fresh fruits, vegetables, unprocessed grains

Maintaining Normal Blood Pressure Through Diet

• Reduce sodium intake

• Increase potassium, calcium, and magnesium intake

• Follow the DASH diet (Dietary Approaches to Stop Hypertension)

Nutrients Essential to Key Body Functions

Vitamins and Minerals: Deficiencies and Food Sources

• Calcium: Dairy, leafy greens, fortified foods

• Magnesium: Nuts, whole grains, leafy greens

• Chloride: Table salt, processed foods

• Phosphorus: Dairy, meat, legumes

• Potassium: Bananas, potatoes, dairy

• Beta-carotene: Carrots, sweet potatoes, spinach

• Vitamin E: Vegetable oils, nuts, seeds

Deficiencies: Each vitamin/mineral has specific deficiency symptoms (e.g., calcium deficiency leads to osteoporosis, vitamin C deficiency causes scurvy).

Which Nutrients Can Be Made in the Body?

• Vitamin D: Synthesized in skin with sunlight exposure

• Niacin: Can be made from tryptophan (an amino acid)

• Vitamin K: Some produced by gut bacteria

Pro-vitamin

• A compound that can be converted into an active vitamin in the body (e.g., beta-carotene is a pro-vitamin for vitamin A).

Nutrients Essential to Healthy Tissues

Bone Development Processes and Timeline

• Osteoblasts: Cells that build bone tissue

• Osteoclasts: Cells that break down bone tissue

• Bone Development Order: Bone formation begins in the embryo, continues through childhood and adolescence, and peaks in early adulthood.

Relationship Between Vitamin D and Calcium

• Vitamin D enhances calcium absorption in the intestines.

• Deficiency in vitamin D can lead to poor bone mineralization (rickets, osteomalacia).

Hypercalcemia

• Excess calcium in the blood, which can cause kidney stones, impaired absorption of other minerals, and abnormal heart rhythms.

Neural Tube Defect

• Birth defects of the brain, spine, or spinal cord due to inadequate folate intake during early pregnancy (e.g., spina bifida).

Antioxidants and Free Radicals

Antioxidants and Their Role Against Free Radicals

• Antioxidants neutralize free radicals, preventing cellular damage.

• Key antioxidant vitamins: Vitamin C, Vitamin E, beta-carotene

Free Radicals: Risk Factors, Formation, and Damage

• Risk Factors: Smoking, pollution, radiation, inflammation

• Formation: Byproducts of normal metabolism, exposure to toxins

• Damage Sites: DNA, cell membranes, proteins

Antioxidant Vitamins

• Vitamin C, Vitamin E, beta-carotene (pro-vitamin A)

What Can Increase or Decrease Risk for Cancer?

• Increase: High intake of processed meats, low fruit/vegetable intake, smoking, alcohol

• Decrease: High intake of antioxidants, fiber, regular physical activity

Blood and Immunity

Leukocytes: Definition and Function

• Leukocytes: White blood cells that defend the body against infection and disease.

Heme vs Non-Heme Iron Sources

• Heme Iron: Found in animal foods (meat, poultry, fish); better absorbed.

• Non-Heme Iron: Found in plant foods (beans, lentils, spinach); less efficiently absorbed.

Other Key Topics

Energy Drinks

• Contain caffeine, sugar, and other stimulants; may cause dehydration and increased heart rate.

Additional info: Academic context and definitions have been expanded for clarity and completeness. Table entries inferred from standard nutrition sources.