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9: Nutrients Important to Fluid and Electrolyte Balance

In Chapter 7, we look at the nutrients important to fluid and electrolyte balance, including water, sodium, chloride, and potassium. We also look at sports drinks, caffeinated beverages, and alcohol.

  • 7.1: Chapter Introduction
    In this chapter we will consider the importance of maintaining fluid and electrolyte balance in the human body, the functions of water and electrolytes in the body, the consequences of getting too much or too little of water and electrolytes, the best dietary sources of these nutrients, and healthier beverage choices. After reading this chapter you will know what to look for in sports drinks and will be able to select the best products to keep hydrated.
  • 7.2: Overview of Fluid and Electrolyte Balance
    Although water makes up the largest percentage of body volume, it is not actually pure water but rather a mixture of cells, proteins, glucose, lipoproteins, electrolytes, and other substances. Electrolytes are substances that, when dissolved in water, disassociate into charged ions. Positively charged electrolytes are called cations and negatively charged electrolytes are called anions.
  • 7.3: Water’s Importance to Vitality
    Of all the nutrients, water is the most critical as its absence proves lethal within a few days. Organisms have adapted numerous mechanisms for water conservation. Water uses in the human body can be loosely categorized into four basic functions: transportation vehicle, medium for chemical reactions, lubricant/shock absorber, and temperature regulator.
  • 7.4: Regulation of Water Balance
    As the food enters your stomach, gastric juice is secreted. As it enters the small intestine, pancreatic juice is secreted. Each of these fluids contains a great deal of water. How is that water replaced in these organs? What happens to the water now in the intestines? In a day there is an exchange of about 10 liters of water among the body’s organs. The osmoregulation of this exchange involves complex communication between the brain, kidneys, and endocrine system.
  • 7.5: Electrolytes Important for Fluid Balance
    Cells are about 75 percent water and blood plasma is about 95 percent water. Why then, does the water not flow from blood plasma to cells? The maintenance of the unequal volumes of water between fluid compartments is achieved by balancing the force of water (hydrostatic pressure) against the force of all dissolved substances. Concentration means the amount of particles in a set volume of water.
  • 7.6: Consequences of Deficiency or Excess
    As with all nutrients, having too much or too little water has health consequences. Excessive water intake can dilute the levels of critical electrolytes in the blood. Water intoxication is rare, however, when it does happen, it can be deadly. On the other hand, having too little water in the body is common. In fact, diarrhea-induced dehydration is the number-one cause of early-childhood death worldwide. In this section, we will discuss subtle changes in electrolytes that compromise health on a
  • 7.7: Water Concerns
    At this point, you have learned how critical water is to support human life, how it is distributed and moved in the body, how fluid balance and composition is maintained, and the recommended amount of fluids a person should consume daily. In America, you have a choice of thousands of different beverages. Which should you choose to receive the most health benefit and achieve your recommended fluid intake?
  • 7.8: Popular Beverage Choices
    In this last section we will discuss three beverage types in particular: alcohol, caffeinated drinks, and sports drinks. We will examine the effects of these beverages upon fluid levels and nutrition within the body so that you will be better able to make wise decisions about your beverage choices.
  • 7.E: Nutrients Important to Fluid and Electrolyte Balance (Exercises)