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					                                  Chapter 5
                           DIGESTION & NUTRITION
I.       Digestion
               Mouth
               Esophagus
               Stomach
               Small Intestine
                     Pancreas
                     Liver
               Large Intestine
II.      Behavior
III.     Summary of Gastrointestinal Hormones
IV.      Disorders of the Gastrointestinal system
Side Bar: Vitamins & Minerals



Goals:
        Describe the path of the alimentary tract
        Describe the three digestive processes: motility, secretion, digestion
        Name three macronutrients and give two examples of each
        List the fat-soluble vitamins and their functions
        List four water-soluble vitamins, their functions and signs of deficiency
        Discuss two disorders of the gasterointestinal system
        Know the definitions for the following words:

         anemia                     lipid
         anorexia                   marasmus
         bulimia Protein            mineral
         carbohydrate               pepsin
         cholesterol                protein
         coenzyme                   rickets
         enzyme                     saliva
         fat                        scurvy
         fiber                      trace element
         Kwashiorkor                trace mineral
         lipid                      triglyceride
                                    vitamin
                                    zymogen




                                              41
                            Digestion & Nutrition

Digestion is the process by which food is broken down into particles small enough to be
absorbed in the gastrointestinal (GI) tract. The primary function of the digestive system is to
transfer nutrients (after modification), water, and electrolytes from the food eaten into the       glucose - one sugar
body's internal environment. Ingested food is essential as an energy source or fuel for cells so    molecule
                                                                                                    (monosaccharide);
they can carry out their energy dependent metabolic functions. Food is also a source of             principle source of energy
building material for the renewal and addition of body tissues.                                     for living organisms.

                                                                                                    sucrose - disaccharide;
The digestive system performs four basic digestive processes: motility, secretion, digestion        obtained from sugar cane,
                                                                                                    beets, other sources.
and absorption. Motility is the muscular contractions that mix and move the food contents
forward within the digestive system. Propulsive movements push the contents through the             fructose - found in honey,
                                                                                                    fruits; a crytstalline sugar.
digestive tract. An example of propulsive movement is the passage of food through the
esophagus. Mixing movements mix the food in the digestive tract with the digestive juices,          Complex and simple
                                                                                                    carbohydrates - refers to
and they facilitate absorption by maximizing exposure of all portions of the intestinal contents    molecular structure.
to the surfaces of the digestive tract. Secretion involves secretion of digestive juices into the
digestive tract lumen by exocrine glands. Digestion refers to the breaking-down process
where structurally complex foods are converted into smaller absorbable units by the enzymes
produced within the digestive system. There are three primary categories of macronutrients
that must be broken-down: carbohydrates, proteins, and fats. As food travel through the five
major portions of the digestive tract: Mouth - Esophagus - Stomach - Small Intestine -
Large Intestine, various enzymes assist with the degradation of these macronutrients.
         Carbohydrates - Carbohydrates are found in food such as breads, pastas, and grains.
         The simplest form of carbohydrates is the simple sugars or monosaccharides (one-
         sugar molecules). Some examples of monosaccharides include glucose, fructose,
         and galactose. Most ingested carbohydrates are in the form of polysaccharides
         (multi-sugar molecules). Polysaccharides consist of chains of interconnected simple
         sugar molecules. One of the most common polysaccharides consumed is starch.
         Glycogen, contained in meat, is the form in which glucose is stored as a
         polysaccharide in muscle. Disaccharides consist of two simple sugar molecules.
         Examples are sucrose (table sugar) and lactose (found in milk). Digestion breaks
         down starch, glycogen, and dissacharides into their constituent monosaccaride forms
         (mainly to glucose). Monosaccharides can be absorbed into the body. Complex
         carbohydrates are generally better nutrients than simple carbohydrates because they
         are typically complexed with other nutrients including fiber (non-digestible plant
         material).




                                               42
                                                                                                      Kwashiokor - a syndrome
                                                                                                      produced by severe protein
           Proteins - Proteins consist of various combinations of amino acids held together by        deficiency. Reversible if mild.
                                                                                                      Found in areas where
           peptide (nitrogen based) bonds. Foods such as meat, fish, poultry, dry beans, eggs,        children are exposed to high
           nuts and soy products are rich in protein. Digestion allows conversion of proteins         starch die; characterized by
                                                                                                      discoloration of hair and skin,
           into their constituent amino acids, which can be absorbed.                                 retardation of growth, and
           Fats - Most dietary fat is in the form of triglycerides. A triglygeride contains a unit    prodtruding abdomen.
           of glycerol and three units of fatty acids. During digestion, two of the fatty acid        marasmus - a form of
           molecules are split off, leaving a monoglyceride (a glycerol molecule with one fatty       protein-caloric malnutrition;
                                                                                                      chiefly occurring during the
           acid attached). Thus, digestion of triglycerides produces monoglycerides and free          1st year of life. Characterized
           fatty acids, which are the absorbable units of fat. Lipids, a complex set of fatty         by growth retardation and
                                                                                                      progressive wasting of
           acids, are abundant in foods such as butter, margarine, oils, fish, red meat, and          subcutaneous fat and muscle.
           poultry. Essential fatty acids must be provided in the diet; the human body is unable
           to synthesize these nutrients on its own. Linoleic acid is one essential fatty acid. Fat
           has a high-energy content 9 kcal/gram (compared to 4 kcal/gram for carbohydrates
           and proteins). High fat diets may increase the chance of developing certain diseases
           such as diabetes (type II) and cancer.                                                     lipids - any of a group of
                                                                                                      organic substances which are
                                                                                                      insoluble in water, but soluble
Absorption occurs after digestion is completed and primarily occurs in the small intestine.           in alcohol and other fat
                                                                                                      solvents, and which have a
Absorption allows small absorbable products of digestion, along with water and vitamins to
                                                                                                      greasy feel. The lipids, which
be transferred from the digestive tract lumen into the blood or lymph.                                are easily stored in the body,
                                                                                                      serve as a source of fuel and
                                                                                                      are an important constituent
                                                                                                      of cell structure.
In the following section, we will cover the roles played by each of these organs in digestion
                                                                                                      cholesterol - a pearly, fat like
as well as provide you with a few examples of a few diseases that impact the digestive                monatomic alcohol,
                                                                                                      crystallizing in the form of
process.
                                                                                                      leaflets or plates, found in
                                                                                                      animal fats and oils, in bile,
                                                                                                      blood, brain tissue, milk, egg
I.         DIGESTION
                                                                                                      yolks, myelin sheaths of nerve
                                                                                                      fibers, liver kidneys, adrenal
                                                                                                      glands.

                                                                                                      triglycerides - a compound
                                                                                                      consisting of 3 molecules of
                                                                                                      fatty acid esterified to
                                                                                                      glycerol; it is a neutral fat
                                                                                                      synthesized from
                                                                                                      carbohydrates for storage in
                                                                                                      animal adipose cells.




                                      Figure 5.1. Human digestive tract




                                                    43
Mouth
                                                                                       saliva - a watery fluid
The mouth is where food enters the body and where digestion begins. Chewing
                                                                                       produced by the
allows food particles to be broken down into smaller food particles. Chemical          salivary glands in the
                                                                                       mouth that contains
digestion begins in the mouth as food is chewed:
                                                                                       lubricants, enzymes
         The enzyme amylase in saliva starts the breakdown of starch.                  (such as amylase) and
                                                                                       other substances



Esophagus
The esophagus is the passageway for food to move from the mouth into the stomach.
The esophagus pushes food into the stomach by mechanical contractions known as
peristalsis. The esophagus does not secrete any enzymes to aid in the process of
food breakdown.


Stomach




                             Figure 5.2. Stomach

The stomach is a J-shaped thick-walled sac that secretes several enzymes and plays a
major role in digestion. Food arrives into the stomach upon the relaxation of the
esophageal sphincter from the esophagus. Once in the stomach, gastric juices
secreted by cells in the walls of the stomach continue the digestive process. The
gastric juice consists of:
         Hydrochloric acid (HCl) – secreted by the parietal cells – HCl maintains a
         highly acidic environment in the stomach. This acidic environment
         functions to: destroy micro-organisms, and pathogens; hydrolyze large




                                     44
         macromolecules to smaller ones; and denature or unravel proteins so they
         can be acted upon by the digestive enzymes.
         Pepsin – secreted by the chief cells - helps break down proteins. It requires
         an acidic environment, provided by the HCl, to function properly.
         Mucus – secreted by the epithelial cells – protects the stomach lining from
         the actions of pepsin and HCl.
Small Intestine




                         Figure 5.3. Small intestine

Food enters the small intestine from the stomach upon relaxation of the pyloric
sphincter. The small intestine is a coiled sac of membranes measuring about 20 feet
long! Unlike the stomach’s acidic environment, the small intestine has an alkaline
environment. The mucosa of the intestine is formed into tiny finger-like projections
called villi. Food absorption occurs through the membrane lining the small intestine,
hence villi increase the surface area of the lining allowing a greater opportunity for
food absorption. A variety of enzymes are secreted into the small intestine, which
further aid in the process of digestion. Unlike the stomach however, the enzymes
secreted into the small intestine are not produced there, rather these enzymes are
produced in the pancreas.


Pancreas
The pancreas is a complex organ that not only aids in digestion but has an endocrine
function as well. To aid in digestion, the pancreas secretes several enzymes in
inactive form called zymogens. Other enzymes present in the small intestine
activate the zymogens by chemical and physical modifications. Enzymes are stored
and secreted in their inactive forms to prevent digestion of the pancreas itself.
Enzymes secreted by the pancreas:
         Pancreatic amylase – digests starch


                                      45
              Pancreatic lipase – digests fat
              Trypsin and chymotrypsin – digest protein


     Liver
     The liver is the largest organ in the body. It functions to aid in food digestion,
     maintain the blood glucose level, detoxify blood or get rid of poisons in blood such
     as alcohol, and it aids in the synthesis and degradation of amino acids, sugars, fats,
     and cholesterol. Bile is produced in the liver and stored in the gall bladder. When
     food enters the small intestine, the gall bladder sends bile through the common bile
     duct to the small intestine. Bile acts as an emulsifier, breaking large fat particles into
     smaller ones. It allows pancreatic lipase to act on a greater surface area by breaking
     fat into smaller particles, thus enhancing the lipase’s activity.


     Large Intestine




                                                                                                  fiber - the part of plants that
                                                                                                  is not digested by
                                                                                                  gasterointestinal tract - acts
                                                                                                  as roughage in diet -
                                                                                                  indications that high fiber
                                                                                                  diet helpful in reducing
                                                                                                  incidence of cancer.

Figure 5.4. Large intestine (colon). There are three main parts to the large intestine, the
               ascending colon, transverse colon, and descending colon.

     The majority of digestion and absorption has occurred by the time that food material
     reaches the large intestine. The food material that arrives in the large intestine is
     essentially waste or indigestible content and is referred to as fecal matter. During the
     process of digestion, a vast amount of water is secreted to aid in the digestive
     process. The large intestine functions to reabsorb this water as peristalsis moves
     fecal matter through it. The smooth muscle lining of the large intestine pushes the
     waste into the rectum and subsequently it is excreted out of the body.




                                            46
      Table 5.1. Summary table of digestion: Organ systems involved and their roles in
      digestion
                          PRIMARY METHOD
           ORGAN                                    ENZYME SECRETED                  FUNCTION
                            OF DIGESTION
                              Chemical &
        Mouth                                       Salivary amylase           Starch digestion
                              Mechanical
        Esophagus               Mechanical          --------                   Peristalsis
                                                    HCl (parietal cells)       Destruction of pathogens
                                                    Pepsin (chief cells)       Protein digestion
                                                                               Protects stomach lining
                                                    Mucus (epithelial cells)
                                                                               from damage by HCl
                                                                               Enhances gastric
        Stomach                  Chemical                                      motility; relaxes the
                                                                               ileocecal sphincter;
                                                    Gastrin (hormone)          induces excretion by the
                                                                               parietal and chief cells;
                                                                               induces colonic matter
                                                                               movement
        Small Intestine                                                        Nutrient absorption
                                                    Pancreatic amylase         Starch digestion
              Pancreas                              Pancreatic lipase          Fat digestion
                                                    Trypsin, Chymotrypsin      Protein digestion
                                                                               Neutralization of HCl in
                                                    Bicarbonate                digestive juices entering
                                                                               small intestine
                                                                               Inhibits gastric emptying
                                                                               and secretion; causes
                                                                               gall bladder secretion;
                                                                               contributes to feeling of
                                                    Cholecystokinin (CCK)
                                 Chemical                                      satiety (fullness after
                                                                               eating); causes
        Small Intestine                                                        relaxation of the
            Cells                                                              sphincter of Oddi
                                                                               Inhibits gastric emptying
                                                    Gastric Inhibitory         and secretion; stimulates
                                                    Peptide                    insulin secretion by
                                                                               pancreas.
                                                                               Inhibits gastric emptying
                                                                               and secretion; stimulates
                                                    Secretin                   secretion of sodium
                                                                               bicarbonate rich bile by
                                                                               the liver
                  Liver          Chemical           Bile (emulsifier)          Emulsification of fat
                                Mechanical                                     Reabsorption of water;
        Large Intestine
                                                                               Peristalsis



II.   BEHAVIOR
      While behavior may not directly impact the mechanical processes of digestion, it
      does influence the overall digestive process by affecting food intake. Intake of food



                                            47
       is based on two primary factors – hunger and appetite. Hunger is the desire for food
       based on a physiological need for food.    An example of this is when your stomach
       “growls” or contracts. This is a mechanism to send a signal indicating that its empty
       and needs to be re-filled. Hunger is satiated a few minutes after chewing begins. It
       is regulated by the hypothalamus and therefore other factors may over ride the
       hunger signaling processes. Appetite is the desire for food that does not have a need
       basis. For example, you might still be hungry for dessert following a big meal.
       Eating disorders generally affect one’s appetite. Anorexia is the loss of appetite due
       to physical and mental disorders. Anorexia nervosa is the loss of one’s appetite to
       the point of starvation, instigated by emotional and social factors, primarily seen in
       young women. Bulimia describes an eating disorder characterized by binging-and-
       purging of food to prevent its absorption. Both anorexia and bulimia are serious
       conditions that lead to morbidity and sometimes even mortality. Treatment for
       eating disorders involves counseling to address the psychological issues motivating
       the eating disorder. Obesity indicates an abnormally high body fat content. Obesity
       can be a risk factor for several conditions such as type II diabetes, deterioration of
       the skeletal system, cardiovascular diseases and stroke. Some physiological
       conditions such as hypothyroidism or a tumor of the thyroid may cause obesity.
       Familial patterns have also been noted in obese patients, however the exact etiology
       of the disease is unknown. Treatment addresses any underlying causes for the
       disease, weight reduction, and counseling.




III.   Disorders of the digestive system
                Dental caries.
                Dental caries, more commonly known as “cavities”, refers to the bacterial
                decay of teeth. Dietary habits, hygiene habits and hereditary factors are the
                leading causes of dental caries. Recently, bacteria have also been
                associated with dental caries. Excessive and untreated dental caries may
                lead to tooth loss, which impairs the mechanical process of digestion. This
                may be due to physical ailments that prevent these individuals from
                maintaining good oral hygiene and from catching the disease in its early
                stages.


                Gingivitis.
                Gingivitis is the bacterial infection of the gums. Is is highly correlated with
                plaque, and its prevention and control requires frequent cleanings and




                                             48
professional care. Gingivitis can lead to tooth loss and possibly to the
destruction of the supporting bone in the mouth. Antibiotic treatments and
frequent dental cleanings usually relieves gingivitis if caught in its early
stages.


Periodontitis
About 30% of people with gingivitis develop periodontitis. Periodontitis
results in the formation of peridontal "pockets", a deepening of the space
between the tooth and gum, that results in loosening of the teeth and
ultimate tooth loss.


Ulcers.
Ulcers are sites of erosion in the mucous lining of a digestive organ. They
can occur almost anywhere in the digestive tract, although common sites are
in the stomach (gastric ulcer) and in the small intestine (pyloric ulcers).
Ulcers most commonly occur in middle-aged persons usually between 30
and 45 years of age. Associative factors include smoking, use of anti-
inflammatory medications and bacterial infection by Heliobacter pylori.
Medications that lower acidic secretion and combat H. pylori are the main
course of treatment for ulcers.


Stomach cancer.
The incidence of stomach cancer has shown a remarkable decline in
industrialized nations. However, it continues to be highly in less developed
countries. Contributory factors which have been credited for the decline of
stomach cancer in the more developed nations include refrigeration of foods
and better sanitation practices. Overall, males tend to have a greater
incidence of stomach cancer than females (68.5/100,000 males and
29.0/100,000 females).


Crohns Disease (CD) and Ulcerative Colitis (UC)
Ulcerative colitis and Crohns disease are of public health importance since
they are difficult to treat, occur primarily in young adults, increase risk of
colorectal cancer, and result in a notable amount of morbidity and mortality
each year. Symptoms are similar for both diseases (abdominal pain,
diarrhea, possible bleeding, and weight loss), however there are some
microscopic differences that differentiate the two diseases. CD involves all




                             49
layers of the intestinal wall and affects either the small or the large intestine,
whereas UC involves the innermost layer of the lower large intestine. Both
diseases occur primarily in those less than 30 years of age and are equally
prevalent in males and females. The etiology of these diseases are unknown,
however, it is hypothesized that they may be the result of an auto-immune
attack or damage to intestinal lining induced by a foreign agent. There is
currently no cure for these diseases; however, symptom management
involves pharmaceutical therapy with antibiotics and corticosteroids along
with nutritional therapy to prevent anemia and dehydration and surgical
removal of the affected parts of the intestine. For more information about
Crohn's disease and ulcerative colitis, refer to www.ccfa.org.


Choleithiasis (Gall Stones)
There are two types of gall stones, depending on their constituent: bilirubin
and cholesterol gall stones. The epidemiology differs by type of gall stone:
for example, risk factors for bilirubin gall stones include increased age,
alcoholic cirrhosis, biliary infection; for cholesterol stone are high calorie
diet, obesity, gastroinestinal disorders, caucasian race, and diabetes. Gall
stones may become lodged in the gall bladder duct, resulting in bouts of
pain. Incidence of gall stones is greater in females than males.
Contributory causes include changes in eating habits such as strict dieting
(loss of more than 4 pounds per week). The common treatment of
gallstones is removal of the duct and gallbladder through laproscopy, a
minimally invasive surgical procedure, or use of ether and sonic shock
waves to break stones apart.


Hepatitis
Hepatitis is an inflammatory disease of the liver that results from a variety
of causes including viral infection or exposure to toxic agents. During viral
hepatitis, the virus reproduces in the nucleus of the hepatocytes, resulting in
cell injury, inflammation, and death of infected cells. There are five viral
types of hepatitis - A, B, C, D, and E. The viruses transmitted by the fecal-
oral route (A, E - also known as "infectious" hepatitis) result in short-lived
or self-limited infections. However, viruses transmitted by blood and body
fluids (B, C, D) result in the production of a persistent infection and chronic
liver disease. Toxic hepatitis occurs due to injury or trauma to the liver




                              50
cells usually from the result of abusive exposure to toxic chemicals or drugs
such as alcohol.


Cirrhosis
Cirrhosis is a condition where damaged hepatocytes (liver cells) are
premanently replaced by connective tissue. The connective tissue
proliferation prevents hepatocyte from receiving a sufficient blood supply
and their growth. As cirrhosis develops over time, active liver tissue is
gradually reduced, leading eventually to chronic liver failure. Usually
patients with cirrhosis do not become symptomatic until three quarters of
their liver tissue has been destroyed in this manner.




                            51
           SIDE BAR: Vitamins & Minerals
Did you know that soft drinks and chocolate are actually good sources of a couple of
vitamins and minerals?! Read below to find out more!

Vitamins
Vitamins are small organic compounds that must be included in the diet because they
cannot be synthesized in the body. They can be obtained from the foods eaten or in       vitamins - a general term
pill form as a supplement to the diet.                                                   for a number of unrelated
                                                                                         organic substances that
                                                                                         occur in many foods in
Vitamins are divided into fat-soluble and water-soluble categories. Fat-soluble          small amounts and that are
                                                                                         necessary for the normal
vitamins require bile acids for solubilization and absorption. Excess fat-soluble        functioning of the body.
vitamins are stored in adipose (fat) tissue and may cause adverse affects if stored in
                                                                                         RDA - Recommended Daily
large amounts. Excess water-soluble vitamins are usually excreted in urine by the        Allowances are set by the
kidneys.                                                                                 Food and Nutrition Board
                                                                                         of the National Research
                                                                                         Council-National Academy
Minerals                                                                                 of Sciences. These are
                                                                                         amounts judged to be
Minerals are trace elements required for normal metabolism, as components of cells       adequate for the
and tissues, and for proper nerve conduction and muscle contraction. They can only       maintenance of good
                                                                                         nutrition in the population
be obtained from the diet. Iron (for hemoglobin), iodine (for thyroxin), calcium (for    of the US.
bones), potassium and sodium (nerve message transmission) are examples of
                                                                                         trace elements - certain
minerals.                                                                                inorganic combinations of
                                                                                         amino acids must be
                                                                                         ingested within certain time
                                                                                         periods for body to make
                                                                                         proteins.




                                         52
                                           Vitamin & Mineral Chart
              Recommended
  Vitamin        Dietary                   Function                       Signs of Deficiency & Toxicity         Nutrient-Dense Sources
               Allowance*

Fat-Soluble Vitamins (A, D, E, K)
          female: 800 g
    A
                          Necessary for growth & repair of                Night blindless
                                                                                                                green leafy vegetables,
                                                                                                                yellow or orange vegetables
             male: 1000 g        body tissues and teeth.
                                                                           xerophthalmia ("dry eye")           (e.g. carrots, sweet
                                 Helps maintain smooth, soft
                                                                           poor growh
                                                                                                                potatoes), milk, liver
                                  disease-free skin
                                 Helps protect the mucous
                                                                           dry skin (keratinization)
                                  membranes of the mouth, nose ,
                                                                      TOXICITY SIGNS:
                                  throat & lungs, thereby reducing
                                  susceptibility to infections;            fetal malformations
                                  protects against air pollutants
                                                                           hair loss
                                 Vision: light and color.
                                                                           skin changes
                                  Counteracts night-blindness &
                                  weak eyesight                            pain in bones

             5 -10 g
    D
                                 stimulates calcium and                   Deficiency may result in rickets
                                                                                                                fortified milk, fish (tuna,
                                  phosphorus absorption from the            (improper mineralization during
                                                                                                                salmon), fish oils, sunlight
                                  gut                                       bone formation resulting in soft
                                 helps control calcium deposition
                                                                            bones) and
                                  in bones                                 osteomalacia (demineralization
                                                                            of previously formed bones
                                                                            leading to soft and brittle bones
                                                                            prone to breakage).

                                                                      TOXICITY SIGNS
                                                                           growth retardation
                                                                           kidney damage
                                                                           calcium deposits in soft tissues
             female: 8 g
    E
                                 Prevents oxidation of unsaturated        Hemolysis of red blood cells
                                                                                                                vegetable oils, whole-grain
                                                                                                                cereals, green leafy
             male: 10 g          fats (antioxidant)
                                                                           Nerve destruction                   vegetables
                                 Helps the body bread down and
                                  use vitamin A.                      TOXICITY SIGNS
                                 Aids in formation and functioning        muscle weakness
                                  of red blood cells and muscle
                                                                           headaches
                                                                           fatigue
                                                                           nausea
                                                                           inhibition of vitamin K
                                                                            metabolism
             60 - 80 g
    K
                                 Necessary for blood clotting.            Vitamin K is synthesized by
                                                                                                                produced in the intestine by
                                                                                                                bacteria, green leafy
                                                                            intestinal bacteria and therefore
                                                                                                                vegetables, liver
                                                                            deficiency is rarely seen.
                                                                            However, long term antibiotic
                                                                            use or fat malabsorptive diseases
                                                                            may result in a deficiency of
                                                                            vitamin K. Symptoms of
                                                                            deficiency include hemorrhagic
                                                                            syndrome.

                                                                      TOXICITY SIGNS
                                                                           anemia
                                                                           juandice




                                               53
Water-Soluble Vitamins
     Vitamin         RDA                  Function(s)                       Deficiency/Toxicity Signs               Nutrient-Dense Sources
B1              1.1 mg
                                  Aids in carbohydrate metabolism         Beri-beri (nervous tingling, poor
                                                                                                                whole-grain and enriched
                                                                                                                breads and cereals,
thiamin
                                  Nervous system functioning
                                                                            coordination, edema, heart
                                                                            changes, weakness)
                                                                                                                fish,meats: pork, poultry,
                                                                                                                sun-flower seeds, milk
B2 riboflavin   1.3 mg
                                  co-enzyme involved in                   inflammation of mouth and
                                                                                                                milk, whole-grain cereals an
                                                                                                                breads, liver, green leafy
                                   cellular/energy metabolism               tongue, cracks at the corners of
                                                                                                                vegetables, mushrooms
                                                                            the mouth, eye disorders
B3              15 mg
                                  co-enzyme involved in fat               Pellegra (diarrhea, dermatitis,
                                                                                                                mushrooms, tuna, salmon,
                                                                                                                meats: chicken, liver, beef,
niacin                             metabolism, fat synthesis, and fat       dementia)
                                                                                                                peanuts, enriched grains
                                   breakdown
                                                                        TOXICITY SIGNS:
                                                                           flushing of skin at >100 mg
B6 pyridoxine   1.8 - 2 mg
                                  formation of hemoglobin                 headache
                                                                                                                beef liver, pork, ham,
                                                                                                                whole-grain cereals,
                                  co-enzyme involved in protein           anemia                              bananas, spinach, broccoli,
                                   metabolism, neurotransmitter
                                   synthesis
                                                                           convulsions
                                                                                                                salmon, sun-flower seeds

                                                                           nausea, vomiting
                                                                           flaky skin
                                                                           sore tongue

                                                                        TOXICITY SIGNS:
                                                                           nerve destruction at doses >500
                                                                            mg
                2.0 g
B12
                                  co-enzyme required for folate           macrocytic anemia
                                                                                                                organ meats: liver, milk,
                                                                                                                poultry, oysters, clams
cobalamine                         metabolism and nerve functioning
                                                                           poor nerve functioning
                                                                                                                (vegetarians should take
                                                                                                                supplements)
C (ascorbic     60 mg
                                  collagen synthesis                      scurvy (poor wound healing,
                                                                                                                citrus fruit, broccoli,
                                                                                                                strawberries, tomatoes
acid)
                                  hormone synthesis
                                                                            pinpoint hemorrhages, bleeding
                                                                            gums, edema)
                                  neurotransmitter synthesis
                                  aids in the absorption of iron
                                                                        TOXICITY SIGNS:

                                  aids in formation of collagen
                                                                           doses >1-2 grams cause diarrhea


                30-100 g
Biotin
                                  co-enzyme involved in glucose           dermatitis
                                                                                                                cheese, egg yolks,
                                                                                                                cauliflower, peanut butter,
                                   production and fat synthesis
                                                                           tongue soreness                     liver
                                                                           anemia
                                                                           depression

                180 g
Folate
                                  formation of red blood cells            megaloblastic anemia
                                                                                                                green leafy vegetables, dark
                                                                                                                yellow or orange fruits and
                                  co-enzyme involved in DNA               inflammation of tongue              vegetables, legumes and
                                   synthesis
                                                                           diarrhea
                                                                                                                nuts, liver, fortified breads,
                                  prevents neural tube defect and
                                                                           poor growth
                                                                                                                cereals, rice, and pastas,
                                                                                                                sun-flower seeds
                                   other neurological problems
                                                                           mental disorders

Minerals
Calcium         800-1200 mg*
                                  aids in formation of strong bones       increased risk of osteoporosis
                                                                                                                milk and dairy products,
                                                                                                                canned fish: sardines and
                                   and teeth
                                                                                                                salmon, collard, kale,
                                  aids in blood clotting
                                                                        TOXICITY SIGNS:
                                                                                                                mustard, spinach, and turnip
                                  helps muscles and nerves function
                                                                           kidney stones in those              greens, fortified orange juice
                                                                            susceptible
                                   (nerve impulse transmission)
                                                                           poor mineral absorption in



                                                 54
                                                                                 general
Phosphorus       700-1250 mg*
                                       aids in formation of bone and           no major deficiency symptoms
                                                                                                                milk and dairy products,
                                                                                                                poultry fish, whole-grain
                                        teeth                                    noted
                                                                                                                cereals, soft-drinks
                                       major ion found in intracellular
                                        fluid
Magnesium        female:280 mg
                                       aids in functioning of muscles,         weakness
                                                                                                                legumes, whole-grain
                                                                                                                cereals, milk, meat, green
                 male: 350 mg           nerves and the heart
                                                                                muscle pain                    vegetables, nuts, chocolate
                                       bone strength
                                                                                poor heart function
Iron             15 mg
                                       part of hemoglobin                      small pale red blood cells
                                                                                                                red meat, liver, dried beans,
                                                                                                                whole-grain cereal, spinach,
                                       used in respiration                     low blood hemoglobin values    tofu, seafood, broccoli, peas
                                       used for immune function
Zinc             females:15 mg
                                       aids in the production of insulin       skin rash
                                                                                                                meats, liver, seafood, whole-
                                                                                                                grain cereals
                 males: 12 mg           and various enzymes (over 200
                                        enzymes need zinc!)                     diarrhea
                                                                                loss of appetite
                                                                                loss of taste
                                                                                hair loss
                                                                                poor growth and development
                                                                                poor would healing


                                                                             TOXICITY SIGNS:
                                                                                reduces iron and copper
                                                                                 absorption
                                                                                diarrhea
                                                                                cramps
                                                                                depressed immune function

                 150 g
Iodine
                                       required for proper thyroid             goiter
                                                                                                                kelp, iodized-salt, white
                                                                                                                bread, saltwater, fish, dairy
                                        functioning (production of thyroid
                                        hormone)
                                                                                poor growth in infancy when    products
                                                                                 mother is deficient during
                                                                                 pregnancy
  *Some RDA values vary by age and gender (average has been provided).



       anemia: refers to a decreased oxygen-carrying capacity of the blood. Caused by various factors

       coenzyme: active form of a vitamin. Coenzymes aid in enzyme functioning.

       megaloblast: a large, immature red blood cell that results from the cell's inability to divide when it normally
       should.

       macrocyte: an enlarged mature red blood cell with a short life span.

       rickets - condition caused by the deficiency of vitamin D especially in infants and children with disturbances
       of normal ossification. Vitamin D and sunlight are cures.

       trace minerals - mineral vital to health that is required in the diet in amounts less than 100 mg per day.

       scurvy - a condition due to deficiency of vitamin C in the diet marked by weakness, anemia, spongy gums,
       and multicutaneous hemorrhages.



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