water and electrolytes

how are things dissolved in water

water is a polar molecule with a negative charge on oxygen and partial positive charge on hydrogens

- universal solvent

total body water percentages

55-60% of body weight

intracellular

2/3 of body weight (28 L);.inside cells

extracellular

1/3 of body weight (14 L); outside cells

---- interstitial (between cells) 70-85%

---- fluid in blood 20-25%

sources of water intake

beverages, food, metabolic water

sources of water loss

urine, sweat, lungs, Gi tract

water intake and retention

thirst is triggered when blood volumes decreases or solute concentration increases

hypothalamus

signals thirst

pituitary glands

releases antidiuretic hormone (ADH) to signal kidneys to conserve water

aldosterone

from adrenal glands, helps retain sodium and water in kidneys

dehydration

caused by not drinking enough water or excessive loss through:

vomiting, diarrhea, fever, sweating, diuretics

Hyponatremia (low sodium)

occurs with excessive water intake -> dilutes blood sodium

water functions

solvent, transport medium, body temp regulation, lubricant, fluid balance

electrolyte functions

fluid and acid-base balance, nerve transmission, muscle function, gastric pH

water and electrolytes

both move from greater area of concentration to area to lesser concentration (passive diffusion)

both move from area with fewer particles to area with more particles (osmosis)

water intake

2500ml daily required to cover loss

sources of sodium

processed foods-> "salty six" sandwiches, pizza, bread, poultry, soup, deli meats

sources of potassium

fruits (bananas, oranges), vegetables (spinach, potatoes), legumes, dairy

adequate intake value for sodium

< 1500 mg/day

adequate intake value for potassium

4700 mg/day

kidneys

responsible for water and waste elimination

- filter blood through nephrons

- control urine output and blood constipation

- regulate electrolyte and water balance

food labels

highlight sodium and potassium

helps consumers lower sodium intake and increase potassium intake

normal blood pressure

120/80

prehypertension

120-129/<80

stage 1 hypertension

130-139/80-89

stage 2 hypertension

140/90

minerals that influence blood pressure

sodium - increases

potassium, calcium, and magnesium - deceases

DASH (Dietary Approaches to Stop Hypertension)

high in fruits and vegetables (potassium)

low-fat dairy products (calcium)

whole grains (magnesium)

low intake of saturated fats and sodium

lifestyle changes for blood pressure

exercise regularly

dont smoke

limit alcohol

reduce sodium intake

DASH diet

manage stress