Water and Electrolyte Balance

• The lecture discusses water and electrolyte balance

Learning Goals

• Differentiate between extracellular, intracellular, interstitial, and intravascular fluid.
• Identify the four main nutrients in water homeostasis and how they perform their tasks.
• Understand the roles of water in the body.
• Describe how fluid is consumed and excreted from the body.

Body Fluid

• The healthy adult body is about 60% water and electrolytes.
• Body fluid is compartmentalized:
  • Intracellular fluid (ICF), consists of about 2/3 of body fluid and is inside cells.
  • Extracellular fluid (ECF), consists of about 1/3 of body fluid and is outside cells.
    • Intercellular fluid, also known as interstitial fluid, is between cells.
    • Intravascular fluid is within the blood and lymphatic vessels.

Body Fluid Variation

• Body fluid varies by tissue type, age, and sex:
  • Lean tissues have a higher fluid content than fat tissues.
  • Lean tissue is lost with age, leading to a decrease of body fluid.
  • Males have more lean tissue/muscle mass, resulting in more body fluid.
• Body fluid is mainly water, but it is also composed of solutes.
• Solutes include electrolytes like sodium and potassium and non-electrolytes like glucose, urea, and proteins.

Roles of Water

• Water dissolves and transports nutrients and waste products.
• Water helps maintain the structure of macromolecules, like glycogen.
• Water is involved in metabolic reactions like hydrolysis and condensation.
• Water acts as a lubricant (e.g., saliva) and cushion around joints and in the spinal cord/brain.
• Water aids in thermoregulation to reduce overall body temperature through sweat.
• Water maintains blood volume.

Electrolytes

• Body fluids comprise electrolytes like sodium, potassium, magnesium, calcium, chloride, and phosphate.
• Electrolytes carry electrical charges.
• Sodium and potassium cations carry a positive charge.
• Chloride and phosphate anions carry a negative charge.
• Fluid has an overall neutral charge because of the balance between electrolytes.
• In intracellular fluid, potassium and phosphate are predominant electrolytes.
• In extracellular fluid, sodium and chloride are predominant electrolytes.

Roles of Electrolytes

• Electrolytes are involved in action potentials (electrochemical gradients involving Na+ and K+) and nerve impulse transmission (action potentials).
• Electrolytes enable the process of muscle contraction (action potential, movement of Ca2+).
• Electrolytes regulate fluid balance by maintaining fluid distribution, maintaining homeostasis.
• Electrolytes balance the acidity of body fluids, therefore regulating acid-base balance.

Water Homeostasis

• To maintain water homeostasis we must control:
  • Total body water
  • Monitor water location (or water ratio)

Sources of Total Body Water

• Metabolic reactions from glucose (C6H12O6 + 6O2 = 6CO2 + 6H₂O+Energy ATP) account for about 10% of total body water.
• Dietary intake makes up the rest.

Losses of Total Body Water

• About 60% of water loss is through excretion (urine and feces).
• About 30% is lost through thermoregulation via sweat.
• About 10% is lost through respiration (lungs).

Health Canada Needs

• Adults need 1.0-1.5 ml of water per kcal expended.
• Infants need 1.5 ml of water per kcal expended.

Water Sources

• Water sources include water, beverages, and food.
• Caffeinated beverages can also increase water loss as caffeine is a diuretic.
• Fruits and vegetables are about 95% water.
• Meats and cheeses are about 50% water.

Situations Requiring Water Homeostasis

• Situations include illness, injury/trauma, taking diuretics, physical activity, change in environment, pregnancy, and lactation.
• The body regulates water balance by excreting the amount needed to maintain equilibrium where intake is equal to excretion
• The body must excrete at least 500ml a day as urine, particularly important for clients with kidney conditions

Imbalances

• Dehydration occurs because of not drinking enough water.
• Water intoxication is a rare condition where the body contains too much water.

Water Intake

• Intake is triggered by thirst, which lags behind hydration status.
• Thirst is sensed by the hypothalamus, and signals such as the concentration of solutes/electrolytes in the blood are monitored.
• When blood sodium concentration increases from eating salty snacks, the hypothalamus sends a message to drink something.

Water Location Homeostasis

• About 2/3 of water is inside cells (intracellular), and 1/3 is outside cells (extracellular).
• Electrolytes, which are either positive (cations) or negative (anions), are dissolved in water.
• Water follows movement of electrolytes in the body.

Roles of Electrolytes in Osmosis

• Electrolytes, particularly sodium, help maintain fluid balance through osmosis.
• Osmosis is the process where water moves through a cell membrane from a dilute solution with more water and fewer electrolytes to a solution with less water and more electrolytes.
• Protein pumps in cell membranes move ions into and out of cells.
• Sodium and chloride are contained outside cells, while potassium and other ions are inside cells.
• Cells regulate water inside and outside them by maintaining specific amounts of sodium outside and potassium inside.

Sodium (Na+)

• Sodium is taken in via table salt, including about 40% Na+ and 60% Cl-.
• Sodium is the principle electrolyte in extracellular fluid.
• Sodium (Na+) is the primary cation regulator of extracellular volume.
• Sodium helps maintain acid-base balance and is essential to muscular contraction and nerve transmission.
• Excess sodium (salt) in the diet contributes to high blood pressure (hypertension).

Key Facts About Sodium

• Sodium deficiencies are unlikely.
• Adequate Intake (AI) is 1500mg/day.
• Tolerable Upper Intake Level (UL) is 2300mg/day or 1 teaspoon of salt, but people with hypertension should not exceed 1500mg.
• Sodium is easily digested, absorbed, and obtained.
• About 10% of sodium is naturally found in food.
• About 15% of sodium is added during cooking.
• About 75% of sodium is added by manufacturers.
• Most dietary sodium comes from salt added into processed foods.

Sodium and Canned Foods

• Processing of food changes the sodium content.
• Processed foods, like canned soup, are high in sodium.
• Consuming too much or too little can be dangerous
• Therefore, it is important to maintain normal sodium intake.

Sodium Deficiencies

• Hyponatremia refers to abnormally low blood sodium, resulting from prolonged vomiting, diarrhea, or sweating during exercise.
• Hyponatremia can also occur in athletes who consume too much water (hyperhydration).
• Hypernatremia refers to abnormally high blood sodium concentration (causes high blood pressure).
• High sodium intakes are correlated with high blood pressure (hypertension), heart disease, and stroke.
• Dietary Approaches to Stop Hypertension (DASH) aims to reduce sodium and increase potassium intakes.
• Increasing physical activity may lower blood pressure.

Chloride

• Chloride is the primary anion (negative ion) regulator of extracellular volume.
• Chloride can move freely to the intracellular space
• Chloride is critical in maintaining fluid, electrolyte, and acid-base balance.
• Chloride makes up part of stomach acid (HCl), maintaining acidity of gastric fluids.
• Table salt and processed foods are the major source of chloride.

Potassium

• Potassium is a major positive ion inside body cells. K+ is the primary cation regulator of intracellular volume.
• Potassium plays a significant role in maintaining fluid and electrolyte balance
• Potassium is involved in maintaining a steady heartbeat, transmitting nerve impulses, and contracting muscles.
• Potassium deficiencies are usually related to excessive losses rather than low intakes.
• Toxicity can result from supplement intake.
• The kidneys accelerate excretion of potassium in times of excess, which accelerates with certain diseases and from medication use.
• Adequate Intake (AI) is 4700mg/day.
• Sources include fresh fruit and vegetables.
• Low potassium intake paired with high sodium intake increases blood pressure and risks death or stroke.
• Hypertension risk is associated with the ratio of sodium to potassium, rather than their individual absolute values.

Dietary Requirements/DASH Diet

• The key is balance between sodium and potassium, approximately 3:1 (K:Na).
• Dietary changes may include decreased sodium intake and/or increased potassium intake.

Phosphorus

• Phosphorus is the body’s second most abundant mineral.
• Phosphorus is the primary anion regulator of intracellular volume-HPO42-.
• Phosphorus has a big role in bone and teeth formation.
• Phosphorus also plays a big role in energy metabolism as part of ATP.
• Phosphorus is an important part of DNA and RNA.
• Lipid containing phosphorus are principle component of all cell membranes. -Phospholipids in lipoproteins helps transport other lipids in the blood

Food Sources of Phosphorus

• Animal protein such as dairy, red meat, and poultry, fish, and seafood, legumes and nuts

Nutrients Involved in Blood Health

• Nutrients that contribute to blood health include iron, zinc, copper, vitamin K, folate and vitamin B12.
• Iron

Learning Goals for Blood Health

• Describe the role of iron for blood health.
• Describe how the iron bioavailability differs and factors that may contribute to this.
• Describe the function of zinc, copper, folate, B12 and vitamin K and their relative contributions to blood health.

About Blood

• Blood transports nutrients such as glucose and oxygen and removes carbon dioxide and waste products.
• Blood provides immune function with white blood cells and is very important for regulating body temperature.
• Blood components are plasma (the majority of blood), white blood cells, platelets, and red blood cells.
  • Plasma is the fluid portion of blood and contains solutes and water.
  • White blood cells are leukocytes and provide immune function.
  • Platelets assist in blood clotting.
  • Red blood cells are erythrocytes which are the oxygen carrier of blood. These contain hemoglobin

Iron & Hemoglobin

• All cells contain iron and component of hemoglobin in red blood cells.
• Most aids with carrying and releasing of oxygen.
• Iron is recycled when red blood cells die (liver saves iron and return to bone marrow- used to build new red blood cells)
• Normal is 10 or 15% of dietary iron absorbed.

Ferritin

• Ferritin, stored iron, is mainly in the liver, spleen, and bone marrow.
• Dietary iron inadaquacy will first affect the body’s ferritin levels

Transferrin

• Transferrin is the body's iron carrying protein, which is produced in the liver.
• Carrys the iron to the tissue for the body, and is combined with ferritin to transport iron where new red blood cells are made.

Hepcidin

• Hormone central to regulating iron balance
• Secreted in the liver in response to elevated blood iron.
• Reduces iron absorption from the intestine and its release from storage
• Iron occurs in two forms in foods: heme and nonheme. Heme Iron (ferrous iron or Fe2+):
• These are found animal products such as meat and fish (part of hemoglobin and myoglobin); have higher absorption than non-heme

Non heme iron

• These are found in plant and animal sources and have a much lower absorption rate.

Iron Absorption Enhancement Factors

• MFP or “meat' factor: This is found in Meat, Fish and Poultry. Promotes both heme and non-heme. It prevents non-heme.
• Vitamin C: promotes non-heme iron absorption. Converts non-heme iron Fe3+ to heme iron Fe2+It can counteract with iron absorption inhibitors.

Iron recycling

• Body loses iron via, sweat, skin, and urine. If bleeding occurs, body can lose iron.
• Transferring carries to blood. Liver (and spleen) dismantles red blood cells and packages iron into transferring, stores excess iron in ferritin
• Bone marrow incorporates iron into hemoglobin and red blood cells, stores excess iron. Muscle cells also needs irom to be delivered

Iron Needs

• Average diet provides 6-7mg in 1000k calories Men usually do not have problem reaching the RDA of 8mg women receive 12-13 mg/dau but need mg during child bearing years. RDA- variable (ferric vs ferrous ) taken into account that shows pregnancy is greater than women greater than men

Iron Deficiency (Anemia)

• most common nutrience deficiency in the workHigh risk - infants and young children along with the elderly women
• vegan dietsHigh peak

Vegeterian/ Vegan Diet Challenges

• They need to follow Canada Food guide by focusing on fortified foods

Mineral Zinc

• assists in the creation of (heme) hemoglobin interacts with platelets in the blood-clotting processes acts as a cofactor for many enzymes.

Functions of Zinc

• It is necessary to assist in production (heme) hemoglobin. It also interacts with blood clots an act as a co factor for many enzymes (i.e. pancreatic).
• It affects thyroid function and contributes insulin storage/ creation. Also tranforms vitamin A.
• Similar to Iron, body can handle or store it. Absorbs influenced by other factorsZinc

Enhancement Factors

• Dietary protein that are more base animals. Enhancing Factors- Phytates that are found in beans.

Food Sources for Vegetarian/ Vegan Diets

• Must fortify foods

Copper

• Serves as constitute for for enzymes. Key factor helping cells use iron.
• The two main roles of is it assists for cell synthesis in the hemoglobin for respiration.

Food soruces for Copper

• organ meats, legumes, whole grains, nut seeds

Vitamins B2

• Both very import in protein metabolism

VItamin K

• K1 from diet from mainly vegetables
• K2 produced in the large intestine by bacteria Vitamin K-

Bones and bone health

• vitamin K is necessary for activation of blood clotting is also necessary for activate process of bone building

Anatomy of bone

• Structure differs in density Trabecular (spongy) – 20% mainly at end.
• Cortical (Compact.) 80 Very dense Most throughout he length.

Bones and bone health: Functions of Bone

The structure of the physical bone is that it is necessary to supply all body organs and allows protects. The bone is necessary to create sites for muscle and movement. - This include Metabolic- Bone store any minerals and this also create blood from this.

The process of Bones developing through three processes

These are- Bone growth- This determine bones size This begins with the womb and in embryotic stage of continues until adulthood Bone modeling-Determine the process of determination bones shape and continuous adults hood Bones Remodeling maintain intercity the process involved in creation of maintain bone.

What is bones remodeling

• bones remodelding involves two components is the prodecures of reabsorption and also production

Resorption

• Is the procedure that the surface breaks down where as the production.

Production

• creates components which are collagens what is made by an osteoblasts .

BONE DEFICIENCIES IN HEALTH

Peak Bones Density is reached to before the age 30- That why when Bone modeling maintains Bones density during early adults hood

Assess of bones health

Assess in DXA that can measure the bone desnsity without is not Invasive

What is the Bones Nutirents

Calcium vitaminD vitamin K and Phosphorus Magniesm Fluroide is also important too

Role of Calcium

The Bone is most aboundt mineral- It import to take edqequte for the sake of Skelton and to prevent bons disuses that come with Age- Ninety Nine is located

Homeostasis in Blood what is need for the body

• To protect you want to have a normal level all the time.
• To protect against Calcium when calcium and absobtio

What Vitamin D is what it has to do with it

• Bone growth maintain blood calcium which is import for for phosphors in cell
• The necessary for the people in northern region who don’t make enough of the vitamin

Dietary Calcium defienies

• When the levels are high Osteoblasts will build up and high and there

Factors of bones

• high peak the factors include best proection aginat all

RIsks in bone

Hihg proek-Best rpotecion against boen lost that all calcium in take youg ages can prevent defincies aginst ostero.

• The factos in osteo ias the deteriate of boen tussiurs .Risk factors in OSteo are Estrogen that is defincey in old femal and testorines that is definecyn in the men

-Modifiabvle

• Sednetrarly lifesyle that that and calcurm Vit.D is need in that

How to find food surcose in calcum

• Most abduont is surcose in calciuc you will ne

What are surcose the most

• Dairy and all other is the most calucim you wull need.
• Vitamin what is necesarry? The need is dependong no sunlgiht that your exposuted you your bodys

Vitamin D

The process of D has a lot to do body of

Bone surcose and the other one is the milk , magrain and ceals- There are low levers of

• Vitamin in bones .

Vegan diet challanfes in vitamnin D-

Vegsns deosnt follow milk products there for if ypu ar a vgan its

Roles of phosphorus in body

Bone stuctures there proatry anons that it inter celluar volumes what assist with .

food surcose for

animal proteins are best surcose for phosphorus.

Magnsum

• Bones strcutres Catlyssim that it for Enrrfgey to the metablosm (Atp) Synthises the process of Portin and fats and membraibne trasport .

Fluroide

• Thsi can strenghn and bones teh and a main the massirite of body

Vitamin and and also Vitamin K

• Vita is aides in podcues in collegen and bones bupdting all that it buolt witho.
• The VIt main for a bone bildnign that ececaillly the otsealcion that is very nesrrssry ot the proces og bomes buldign