Chapter 11
 Diet and Nutrition - Notes  (Changes and Suggestions in blue - 3/6/06)
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 1. Name the four main uses of nutrients in the body.

     1. energy for activities
     2. raw materials (e.g., growth, repair, and replacement)
     3. cofactors to assist reactions (e.g., vitamins, minerals)
     4. fluid/electrolyte balance (e.g., osmotic pressure, blood pressure)

 2. Describe the correlations between proper diet and proper nutrition (nutritional homeostasis).

     - normally, proper diet -> proper nutrition
     - sometimes proper diet does not -> proper nutrition
          - e.g., digestive malfunction, disease, smoking, alcohol, medications

3. Explain why malnutrition can have diverse effects

     - many possible types of malnutrition
     - diversity in severity and duration of malnutrition
     - diversity in direct and indirect effects from malnutrition

 4. Explain why malnutrition may be difficult to detect.

     1. body nutrient reserve may delay onset of S&S
     2. S&S may be mild or develop gradually
     3. S&S may be attributed to other problems (e.g., dementia)

 5. Describe overall effects from malnutrition.

     1 decr. homeostasis
     2. decr. quality of life
     3. incr. diseases (e.g., atherosclerosis, osteoporosis)

6. Describe and evaluate methods for determining a proper diet.

     - Food Guide Pyramid
          - based on ordinary foods
          - not designed for different age groups
          - may have low levels of Vitamin C and fiber
          - may have too much fat
          - not individualized
          - see new Food Guide Pyramid for elders
            To see the new Food Guide Pyramids, updates and applications, go to .
                For an animated explanation of the new Food Guide Pyramid, go to

            To see information about a specialized Food Pyramid for elders, go to .
                    To download this Food Pyramid, go to
     - Recommended Dietary Allowances (RDAs)
          - comprehensive and detailed
          - includes caloric intake
          - does not include many minerals
          - uses broad age categories
          - may have inadequate protein
          - not individualized
            To see all the Recommended Dietary Allowances (RDAs) and the Dietary Reference Intakes (DRIs), go to .

     - U.S. Recommended Daily Allowances (U.S. RDAs)
          - comprehensive and detailed
          - does not include many minerals
          - uses broad age categories
          - may have inadequate protein
          - not individualized

                The U.S. RDAs have been replaced by the Reference Daily Intake (RDI). The list includes only values for protein, vitamins, and minerals for use in nutrition labeling. The values for the U.S. RDAs are essentially the same as those in the RDIs except for protein, though the RDIs may be changed. A table listing the RDIs is within the document .

                The RDIs are also listed at . The list includes only nutrients with values listed in the Daily Reference Values (DRVs) and the Reference Daily Intakes (RDIs).

                New definitions and descriptions of the nutritional terms and Reference Daily Intakes (RDIs), Daily Values (DVs), Daily Reference Values, (DRVs), and Recommended Dietary Allowances RDAs can be found at
     - Estimated Safe and Adequate Daily Dietary Intakes (ESADDIs)
          - compliments the RDAs
          - uses broad age categories
          - not individualized
            The ESADDIs are published in Recommended Dietary Allowances: 10th Edition, Food and Nutrition Board, Commission on Life Sciences, National Research Council (1989). A free on-line version can be seen by going to . The ESADDIs are in the Summary Tables at .
     - Dietary Reference Intakes (DRIs)
          - comprehensive
          - includes diverse age categories
          - versatile
          - complex
          - not individualized
            An on-line version of the reference book Dietary Reference Intakes: Applications in Dietary Planning (2003) from the Food and Nutrition Board and the Institute of Medicine is at .

The tables of Dietary Reference Intakes are at and at .

 7. Compare and contrast nutritional needs for younger and older adults.

     - same because of same body functions
     - adjust kcals based on activity levels
     - modify based on abnormal or unusual conditions
          - e.g., heat, cold, exercise, disease, meds

8. Explain why a diet plan for an elderly person must be more individualized.

     - increased heterogeneity in lifestyle; amount of exercise; diseases; medications; levels of activity; disabilities; sensory, motor, and mental problems, social, economic, psychological

    - see supplementary table Factors that Influence Amounts and Types of Food Eaten

 9. Describe the general trends in malnutrition as age increases and explain reasons for these trends.

     - increased incidence and severity as age increases
     - numerous and diverse reasons including biological, social, psychological, economic
        - see supplementary table Factors Contributing to Malnutrition in the Elderly

 10. Describe an appropriate sequence of steps to prevent or reduce malnutrition.

     1. evaluate nutritional status
     2. identify factors contributing to malnutrition
     3. make adjustments in diet and activity to improve nutrition
           - individualize adjustments
           - combine nutrition with other activities
           - use selected supplements, medications
     4. reevaluate and adjust as circumstances change (e.g., disease, finances, psychology, social, level of activity)

 11. Briefly describe the body's energy economy and energy balance including the contributions made by (1) BMR, (2) muscle activity, and (3) defense and healing processes and age-related changes in these parameters.

     1. BMR = resting rate of energy use
           - due to respiratory action, muscle metabolism, brain and liver metabolism, digestion, maintaining body temperature, growth, turnover of cells (e.g., skin, digestive mucosa), healing
           - depends heavily on muscle mass
           - aging -> variable but general decr. due to decr. muscle mass
     2. muscle contraction -> very large and variable contribution
           - aging -> variable but general decr. due to decr. activity
     3. defense and healing -> very variable contribution
           - important for elderly due to incr. number and severity of diseases
           - aging -> variable but often incr. due to incr. abnormal and disease conditions

12. Describe strategies to maintain energy balance and nutritional homeostasis.

     1. decr. kcals but incr. nutrient density when decr. energy needs
     2. incr. activity to allow incr. eating with no weight gain

13. Describe effects from being obese and being underweight.

     - obesity (see supplementary table Problems Increased by Obesity)
          - adverse effects on many body system; increases risk of many diseases; social, psychological, economic impact
             For the U.S. National Library of Medicine and NIH comprehensive web site about obesity, go to .

            For “Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults” by the National Heart, Lung, and Blood Institute, go to . For a PDF file of report on obesity, go to . Go to page 12 of the report for the section on health risks and other outcomes from obesity (e.g., social, psychological). For the NHLBI BMI calculator, go to or (suggested by Zara Henderson). For the NHLBI web page with tips and information about healthy weight, overweight, and underweight, go to and to

For the Centers for Disease Control and Prevention web site on “Overweight and Obesity”, go to . It has links to diverse topics about obesity and weight control (e.g., contributing factors, trends, consequences, recommendations, BMI calculators) .

            For the Merck comprehensive web site about obesity,  go to .

     - underweight
          - weakness, fatigue, decr. body temp. regulation in cold, decr. resistance to abnormal and disease conditions, decr. body reserves for use during stress periods (e.g., recovery from illness)

14. Name the overall uses for the following dietary nutrients: digestible carbohydrates (CHOs), fiber, lipids, proteins, water, vitamins, minerals

     - digestible CHOs -> energy, raw materials
     - fiber -> aids to large intestine functioning, decrease cholesterol absorption, slows glucose absorption (diabetes)
     - lipids -> energy, raw materials, vitamin absorption, essential fats for essential body molecules (e.g.,. for clotting factors, regulating BP, immune system),
     - proteins -> energy, raw materials, essential amino acids
     - water -> aid digestion, temperature regulation, circulation, cell size and shape (osmotic pressure)
     - vitamins -> assist in many reactions
     - minerals -> building material, assist reactions, nerve and muscle functions

15. Name problems resulting from having inadequate or excessive levels of carbohydrates, lipids, proteins, water, vitamins, and minerals.

     -  see supplementary tables Limiting Intake of Fat, Saturated Fat, and Cholesterol  Facts About VitaminsFacts About Individual Minerals

16. Describe the general characteristics of a diet that can provide proper nutrition and explain the underlying reasons for these characteristics.

     - eat a variety of foods in moderation to obtain a complete mixture of the many and varied nutrients needed to support the body's many and varied structures and functions.

17. Explain in general terms why obtaining an adequate diet to obtain nutritional homeostasis becomes more difficult as age increases and why dietary planning must be more individualized as people age.

     - incr. adverse age changes, incr. abnormal conditions, incr. diseases, and incr. use of medications in many systems plus adverse social, psychological, and economic changes - > difficulty selecting, obtaining, preparing, eating, and digesting foods and in absorbing and using nutrients

18. Discuss the interactions between nutrition and alcohol consumption, medications, and disease.

    - see supplementary table Effects of Alcoholism on Nutrients

19. Describe caloric restriction (CR) and its effects on ML and XL.

     - CR is reduced caloric intake without malnutrition for specific nutrients
     - results in increases in ML, in XL and in general health of most animal species studied
     - only known technique that increases XL
            For the Wikipedia on-line encyclopedia site on caloric restriction, go to .

            For the NIA web page on caloric restriction, go to restriction

            For the Caloric Restriction Society web site, go to.


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© Copyright 1999 - Augustine G. DiGiovanna - All rights reserved.
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