Nutrition 202- TAMU- Minerals-Exam 3

Module 1 - Minerals

Learning Outcomes for Chapter 8 (1 of 2)

  • 8.1 Explain the importance and functions of water in the body.

  • 8.2 Describe water balance and how the body maintains it.

  • 8.3 Identify daily water needs and the best sources for it.

  • 8.4 Explain what minerals are and why you need them.

Learning Outcomes for Chapter 8 (2 of 2)

  • 8.5 Name functions, sources, and deficiency/toxicity symptoms of:

    • Sodium

    • Potassium

    • Calcium

    • Phosphorus

    • Magnesium

    • Chloride

    • Sulfur

    • Iron

    • Copper

    • Zinc

    • Selenium

    • Fluoride

    • Chromium

    • Iodine

    • Manganese

    • Molybdenum

Importance of Water (1 of 2)

  • Abundance: Water is the most abundant substance in the body.

    • Average healthy adult is about 60% water.

    • Muscle tissue is approximately 75% water, while fat is around 20% water.

  • Survival Factor: Can survive only a few days without water.

  • Distribution: Water is balanced among fluid compartments:

    • Intracellular fluids: Inside cells.

    • Extracellular fluids: Interstitial fluid between cells and fluid in the blood.

  • Electrolytes: Minerals that help maintain fluid balance.

Importance of Water (2 of 2)

  • Functions:

    • Acts as a universal solvent and transport medium.

    • Medium for chemical reactions in body.

    • In blood, helps transport oxygen, nutrients, and hormones to cells.

    • In interstitial fluid, helps transport waste products away from cells for excretion.

    • Thermoregulation: Helps maintain body temperature by transporting heat and aiding in sweat evaporation.

    • Lubrication and Protection:

    • Acts as a lubricant for joints, eyes; part of mucus and saliva.

    • Provides protective cushioning for the brain, organs, and fetus.

Water as Part of Body Fluids

  • Fluid Compartments:

    • Extracellular fluid compartments include blood and interstitial fluids.

    • Intracellular fluid compartment includes all fluids within cells.

Water Balance and Maintenance

  • Definition: Water balance is achieved when water consumed equals water lost.

  • Intake Sources:

    • Beverages and food.

  • Loss Regions:

    • Water is lost through kidneys (urine), large intestine, lungs, and skin.

    • Insensible Water Loss: Evaporation from skin and respiration.

    • Sensible Water Loss: Through urine, feces, and sweat.

Dehydration (1 of 2)

  • Causes: Can result from inadequate water intake or excessive water loss (e.g., diarrhea, vomiting, high fever, diuretics).

  • Thirst Mechanism:

    • Triggered by dry mouth due to increased electrolyte concentration in blood and decreased blood volume.

    • Increased sodium concentration prompts the brain to signal thirst and the secretion of antidiuretic hormone (ADH) to reduce urine output.

    • Fluid moves from inside cells to blood by osmosis.

Dehydration (2 of 2)

  • Indicators of Dehydration:

    • Cornerstone Method: Measure body weight before and after exercise.

    • Weight loss = water loss.

    • Urine Color Monitoring:

    • Darkening urine color indicates concentration and potential dehydration.

Hyponatremia

  • Condition: Caused by consuming too much water leading to too little sodium in the blood.

  • Vulnerability: Rare among healthy individuals on a balanced diet but can occur in soldiers training and endurance athletes.

Daily Water Needs and Sources

  • Variability: Daily water needs depend on physical activity, environment, and diet.

  • Recommendations:

    • Men: 16 cups/day (about 13 cups from beverages).

    • Women: 12 cups/day (about 9 cups from beverages).

    • Sources: Approximately 80% from beverages and 20% from food.

Food Water Content

  • With High Water Content:

    • Vegetables (>70% water): e.g., lettuce and tomatoes.

    • Fruits (>90% water): e.g., watermelon.

  • Moderate Water Content:

    • Dairy, grains, and protein foods typically have lower water content.

Tap Water vs Bottled Water

  • Myth: Bottled water is purer than tap water.

  • Reality: Tap water is safe, monitored by the Environmental Protection Agency (EPA), and often fluoridated.

  • Bottled Water:

    • FDA requirements apply; may be tap water; often more expensive.

    • Various types include mineral water, spring water, distilled water, flavored water, and vitamin/enhanced waters.

What Are Minerals?

  • Definition: Inorganic elements necessary in small amounts.

  • Absorption Influences:

    • Bioavailability affected by competition (e.g., excess zinc reduces copper absorption).

    • Binding substances (e.g., oxalates in spinach block calcium absorption).

Types of Minerals

  • Major Minerals (Macrominerals): Required in amounts greater than 100 mg/day.

  • Trace Minerals (Microminerals): Required in amounts less than 15 mg/day.

Major Minerals Functions

  • Sodium, chloride, potassium, magnesium, and sulfur are crucial for fluid balance.

  • Calcium, phosphorus, magnesium strengthen bones.

Trace Minerals Functions

  • Vital roles similar to major minerals but in smaller quantities.

  • Chromium and iodine help manage hormone function; iron maintains healthy red blood cells.

Mineral Toxicity and Deficiency

  • Toxicity Potential: Overconsumption can lead to adverse effects; generally arises from supplements rather than food.

  • Varied Diet Importance: Emphasizes the necessity of a diverse diet to mitigate risks of both deficiency and toxicity.

Overview of Major Minerals and Trace Minerals

  • Major Minerals: Include sodium, potassium, calcium, phosphorus, magnesium, chloride, and sulfur.

  • Trace Minerals: Include iron, copper, zinc, selenium, fluoride, chromium, iodine, manganese, and molybdenum.

Tables and Figures Summary

  • Figures and tables provide visual representation of various minerals, their functions, recommended intake, food sources, and symptoms of deficiency or toxicity for easier understanding.

  • Tables include:

    • Major and Trace Minerals at a Glance: Functions, DRI, sources, symptoms of deficiency/toxicity.

Exploring Sodium

  • Role: Essential for fluid balance; major electrolyte outside cells; often consumed as sodium chloride.

  • Sodium Balance: Maintained via kidneys adjusting excretion.

  • Daily Requirements: 1,500 mg/day for adults aged under 51; dietary guideline under 2,300 mg/day.

  • Sources: Processed foods, table salt, meat, seafood, and dairy.

  • Too Much or Too Little: Rare deficiency; excessive intake linked to hypertension.

  • Blood Pressure Relation: Important in managing blood pressure, which is defined as the force of blood against artery walls (systolic/diastolic).

Exploring Potassium

  • Functions: Aids fluid balance, muscle contractions, nerve impulses, and may help lower hypertension.

  • Daily Needs: 2,600 mg for women; 3,400 mg for men.

  • Sources: Fruits and vegetables optimally; dairy and legumes are supplementary.

  • Symptoms of Imbalance: Hyperkalemia from excess; hypokalemia from too little can be dangerous.

Exploring Calcium

  • Abundance: Most significant mineral; over 99% in bones and teeth.

  • Functions: Bone and teeth maintenance alongside muscle contraction and nerve transmission.

  • Daily Needs: 1,000-1,200 mg/day depending on age.

  • Sources: Dairy, green leafy vegetables, certain fish, and calcium-fortified products.

  • Upper Limits: Excessive intake can lead to hypercalcemia and associated health issues.

Osteoporosis

  • Meaning: Condition characterized by low bone density, leading to increased fracture risk.

  • Risk Factors: Include age, gender, ethnicity, physical activity, hormone levels, medication use, and overall nutrition.

Exploring Phosphorus

  • Overview: Constitutes a significant portion of bone composition and is central to energy storage and metabolism.

  • Daily Needs: 700 mg for adults.

  • Sources: Meat, dairy, poultry, and cereals.

  • Toxicity and Deficiency: Potential for hyperphosphatemia; deficiency leads to serious health issues.

Exploring Magnesium

  • Functions: Vital for over 300 enzyme systems and essential in muscle function, heart rhythm, and bone health.

  • Daily Needs: Approximately 310-420 mg depending on age and sex.

  • Sources: Whole grains, nuts, and green vegetables hold significant magnesium content.

  • Toxicity Consideration: May arise from excessive supplements, specifically.

Exploring Chloride and Sulfur

  • Chloride: Integral to stomach acid, aiding digestion; daily needs align with sodium.

  • Sulfur: Part of amino acids; vital in protein shape but lacks established toxicity levels.

Iron and Trace Minerals Overview

  • Iron Functions:

    • Critical for oxygen transport in hemoglobin; daily needs vary by sex and age.

    • Deficiency prevalent and can lead to anemia.

  • Copper: Essential for iron transport and enzyme function.

  • Zinc: Supports immune function and enzyme reactions; sources include meat and grains.

  • Selenium: Acts as antioxidant and contributes to thyroid hormone regulation.

Conclusion on Implications of Mineral Intake

  • Nutritional Approach: Emphasizing variety and balance in diet optimizes mineral intake, avoiding deficiencies and toxicities.

Additional Lesser-Known Minerals

  • Arsenic, Boron, Nickel, Silicon, and Vanadium: Compounds with suggestive roles in metabolism and potentially varying levels of required intake and observed toxicity.

-- Understanding and application of mineral knowledge is vital in maintaining health and preventing disease. --