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Nutrition Test 1
The Human Body: From Food to Fuel
Taste and Smell
- Sight, smell, thought, taste and sound
o Trigger a set of responses that prepare the digestive tract to receive food
o Muscle contractions around stomach causes grumbling in stomach
The Gastrointestinal Tract
- Variety of functions, including:
o Ingestion of food
o Transport of ingested food
o Secretion of digestive enzymes, acid, mucus and bile
 Mucus:
 helps move food through the intestinal tract
 immune function by holding onto pathogens long enough to be
identified by the body
- Several layers to the GI tract, including
o Mucosa
 Produces mucous and secrets it into GI
o Circular muscle
 Can squeeze only in one direction
o Longitudinal muscle
o Sphincters
 Prevent backflow form one organ to the other
Overview of Digestion
- Physical Movement
o Peristalsis: movement of food
 Wavelike, muscular contractions
 Transport food and nutrients along the GO tract
o Segmentation: breakdown of food
 Series of muscular contractions in the small intestines
 Divides and mixes the chyme
- Chemical Breakdown
o Enzymes
 Proteins that catalyze chemical reactions
o Other secretions
 Acid
 HCL
 Base
 Neutralizes the acid
 Mucus
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
Bile
 Large fat molecules to small fat molecules
 Made in liver, stored in gallbladder**
 Pancreas secretes bicarbonate that neutralizes the HCL
Overview of Absorption
- Passive diffusion
o Normal concentration gradient: High to low
o No energy required
o Fat soluble molecules, some gasses ad water
- Facilitated diffusion
o Normal concentration gradient: High to low
o Doesn't’t require energy
o Requires a protein channel*
o Water soluble molecules, must fit through the channel
- Active transport
o Requires energy, ATP
o Move molecule against normal concentration gradient
o ATP changes shape of protein channel
- Co Transport
o Carbohydrates and glucose
o Requires another molecule, usually sodium
o Uses protein channel
 Glucose get attached to sodium molecule and sodium moves along
natural concentration molecule with glucose attached
o Moving something against the concentration gradient
o No ATP
Assisting Organs
- Salivary glands
o Moisten food
o Supply enzymes
 Begin starch and lipid digestion
 NO PROTEIN DIGESTION in Mouth
- Liver
o Produces Bile
 Large fat molecules to small fat molecules
o “Chemical factory”
 Monitors what is going on in the body
 Holds on to sugar and stores it
o “Dynamic warehouse”
- Gallbladder
o Stores and secretes bile
- Pancreas
o Secretes bicarbonate
 Neutralizes HCL acid
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o Secretes digestive enzymes
- Mouth
o Enzymes in Saliva
 Salivary amylase acts on starch (carbs/sugars)
 Lingual lipase acts on fat
o Saliva
o Moistens food for swallowing
Salivary gland
- Largest: Parotid in cheek
- Sublingual under tongue
- Submandibular under mandible
Digestion and Absorption
- Esophagus
- Transports food to stomach
- Esophageal sphincter
o Upper
o Lower
 Between esophagus and stomach
- Stomach (lipids and proteins)
o Hydrochloric acid prepares protein for digestion and activates enzymes
 Pepsinogen inactive form of pepsin
 HCL rises leads to Pepsinogen turning to pepsin
- Pepsin begins protein digestion
- Gastric lipase has some fat digestion
- Gastrin (hormone) stimulates gastric secretion and movement
- Intrinsic factor is needed for absorption of vitamin B12***
o Not used until intestine
Digestion and Absorption
- Pyloric Sphincter: Stomach to Small intestine
- Small intestine
o Sections of small intestine
 Duodenum
 Primary area for digestion
o Proteins to amino acids
o Carbs to monosaccharides
o Fat to Fatty acids and glycerol
 jejunum, and ileum
 Absorption
o Nutrient digestion
 Bicarbonate neutralizes stomach acid
 Pancreatic and intestinal enzymes
 Carbohydrates (jejunum)
 Fat (beginning)
 Protein (ileum)
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o Absorption
 Folds, villi, and microvilli expand absorptive surface
 Most nutrients absorbed here
 Fat-soluble nutrients go into lymph
 Lacteal: entry into lymphatic system
 Other nutrients go into blood
 Lipids and carbohydrates, water soluble vitamins: hepatic portal
vein
Digestion and Absorption
- Ileocecal valve: from small to large intestine
- Large intestine
o Sections
 Cecum
 colon: reabsorbing water, release/absorb vitamin K and B12
 rectum: holds feces
 anal canal
o Digestion
 Peristaltic movement is slow, taking 18–24 hours for material to travel
 Some digestion of fiber by bacteria
o Absorption
 Water
 Sodium, potassium, and chloride
 Vitamin K (produced by bacteria)
o Elimination
Circulation of Nutrients
- Vascular System
o Veins and arteries
o Carries oxygen and nutrients to tissues
o Removes wastes
- Lymphatic system
o Vessels that drain lymph
o Empties into the bloodstream near the neck
 Thoracic duct to vena cava
- Excretion and elimination
o Lungs
 Excrete water and carbon dioxide
o Kidneys filter blood
 Excrete waste; maintain water and ion balance
Signaling Systems: Command, Control and Defense
- Nervous system
o Regulates GI activity
 Enteric nervous system
 Component of Autonomic
 Autonomic nervous system
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o Hormonal system
 Increases or decreases GI motility and secretions
 Influence your appetite
- Immune system
o Protects us from foreign invaders
o Role of GI tract
 Barrier
 Immune response
 Natural killer cells
 Macrophages
 Location of lymphoid tissues
 Lymphocytes
o Antibodies
Influences on Digestion and Absorption
- Psychological influences
o Taste, smell, and presentation of food
- Chemical influences
o Type of protein you eat and the way it is prepared
- Bacterial influences
o Hydrochloric acid kills most bacteria
Nutrition and GI Disorders
- Constipation
o Hard, dry, infrequent stools
o Reduced by high fiber, fluid intake, exercise
- Diarrhea (pathogen/infection)
o Loose, watery, frequent stools
o Symptom of diseases/infections
o Can cause dehydration
o Broth, tea, toast, and other low-fiber foods can help reduce
- Number 1 GI disorder is gas
- Constipation in Pregnant women is caused by
o Baby squishing digestive tract
o Baby produces hormones to slow down GI tract to increase digestion
- Elderly
o Muscles atrophy
o Die from diarrhea due to dehydration
Nutrition and GI disorders
- Diverticulosis
o Pouches along colon
 Food becomes stuck in pouches and become inflamed/infected
(diverticulitis) **
o High-fiber diet reduces formation
o Increases with age
- Heartburn and GERD
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o Reduced by smaller meals, less fat
o Smoking weakens the esophageal sphincter
o Being overweight often worsens symptoms
Nutrition and GI disorders
- Irritable bowel syndrome (caused by multiple pathogens)
o Causes abdominal pain, diarrhea or constipation, and cramps
o Stress and certain foods aggravate the symptoms
o Can usually be controlled by diet and lifestyle modifications
 Stress management
- Colorectal cancer
o Fiber-rich diet may reduce risk
- Gas
o Most foods that contain carbohydrates can cause
 Not rice
- Ulcers
o Pain in the upper abdomen
o Can cause nausea, vomiting, loss of appetite, and weight loss
o Bacterial cause (H. pylori)
 98% caused by H. Pylori
 Alcohol and anti inflammatory drugs are other 2% causes
- Functional dyspepsia
o Chronic pain in the upper abdomen
o Treat with medicine and stress reduction
 Treated with antibiotics
 Crohne's Disease
 Immune system attacks intestinal cells
 Immunosuppressant drugs
 Part of colon removed
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Food Choices: Nutrients and Nourishment
The Science of Nutrition
- Identifies amount of food we need
- Recommends best food sources
- Identifies components in food that are helpful or harmful
- Helps us make better choices
o Improves our health
o Reduces our risk of disease
o Increases our longevity
Why do we eat the way we do?
- Personal Preferences
o Enjoyment
 Celebrate around food
o Nourishment
o Age
 Taste changes with age
- Sensory Influences: Taste, Texture and Smell
o Flavor: Combo of taste, texture and smell
o Classic tastes: Sweet, sour, bitter, salty and umami
- Social, Emotional and Cognitive Influences
o Habits
o Comfort/Discomfort Foods
o Advertising and Promotion
o Eating away from home
o Social Factors
o Nutrition and health benefits
- Environmental Influences
o Economics
 What is available for you, location and transportation
o Lifestyle
o Availability
o Cultural Influences
o Religion
The American Diet
- How healthful is the “American” diet?
o Too few nutrient-dense foods
 Fruits, vegetables, low-fat dairy, and whole-grain foods
- Too much of the foods known to be harmful
o Sodium, solid fat, saturated fat, and sugar
Introducing the Nutrients
- Nutrient
o Functions
 Normal growth and development
 Maintaining cells and tissues
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

Fuel to do physical and metabolic work
Regulating body processes
 Producing ATP
o Six classes of Nutrients
 Carbohydrates (macro)
 Lipids (fats and oils) (macro)
 Proteins (macro)
 Vitamins (micro)
 Minerals (micro)
 Water (macro)
o Definition of Nutrients
 Absence from the diet results in a specific change in health
 Putting the chemical back in the diet will reverse the change in health
 Not only chemicals in food
 Phytochemicals
 Antioxidants
Classifications of Nutrients
- Macronutrients
o Carbohydrates, lipids, and proteins
- Micronutrients
o Vitamins and minerals
- Organic (contain carbon)
o Carbohydrates, lipids, proteins, and vitamins
- Inorganic (c and H but not both)
o Minerals and water
Introducing the Nutrients
- Carbohydrates
o Sugars and starches
o Functions
 Energy source
- Lipids
o Triglycerides (fats and oils), cholesterol, and phospholipids
o Functions
 Energy source, structure, regulation
o Food sources
 Fats and oils, Meats, Dairy products
- Proteins (second most important nutrient after water)
o Made of amino acids
o Functions
 Energy source, structure, regulation
o Food sources
 Meats, Dairy products, Grains, legumes, vegetables
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Vitamins
o Functions
 Regulate body processes
 Co- enzyme
 Play a vital role in extracting energy
o Fat-soluble
 A, D, E, K
o Water-soluble
 B vitamins, vitamin C
o Food sources: All food groups
- Minerals
o Macrominerals
o Microminerals, or trace minerals
o Functions
 Structure, regulation
o Food sources
 All food groups
- Water
o Most important nutrient
o Functions
 Temperature control
 Lubrication of joints
 Transportation of nutrients and wastes
o Food sources: Beverages and Foods
Nutrients and Energy
- Energy
o The capacity to do work
- Energy sources
o Carbohydrates, lipids, protein
- Measure of energy
o Kilocalorie
o 1,000 calories = 1 kilocalorie
Energy in Foods
- When is a kilocalorie a calorie?
o Calorie: c
o Kilocalorie: C
 Specific measurement or unit of
energy in food
 General term for energy in food
- Lipids: 9kcal/g
- Carbs: 4 kcal/g
- Protein: 4kcal/g
- Alcohol: 7 kcal/g
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Calculating Energy for Food
- Example:
o 30 g carb × 4 kcal/g = 156 kcalories
o 10 g protein × 4 kcal/g = 40 kcalories
o 16 g fat × 9 kcal/g = 144 kcalories
TOTAL = 340 kcalories
- Calculate the Percentages of Calories in Food
Diet and Health
- What does it mean to be healthy?
o WHO defines health as “a state of complete physical, mental, and social wellbeing and not merely the absence of disease or infirmity”
- Disease is “an impairment of the normal state of the living animal … that interrupts or
modifies the performance of the vital functions”
o Food choices are most likely to affect our risk for developing chronic diseases
- Physical activity
o Sedentary lifestyle
 Risk factor for chronic disease
o Role in long-term weight management
 At least 30 minutes per day of moderate activity
 10 min bouts
 Reduce chronic disease risk
 At least 60 minutes per day
 Weight-management
Applying the Scientific Process to Nutrition
- The Scientific Process enables researchers to test the validity of hypotheses
o Hypothesis: Proposed explanation made on the basis of limited evidence as a
starting point for further investigation
- Used to expand our nutrition knowledge
Common study designs
- Epidemiological studies
o Studies of populations, usually comparing populations
- Animal and cell culture studies***
o Impact on individuals, give us an idea of something to look for but rarely
transfers from mice to humans
- Case control studies
o People with diseases to find causes or what is happening
- Clinical trials
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o Randomized
o Double-blind
 researcher and participant don’t know who is in what group
o Placebo-controlled
From Research Study to Headline
- Publishing experimental results
o Scientists publish results of experiments in scientific journals to communicate
new information
o Peer review process reduces chance that low-quality research is published
- Sorting facts and fallacies in the media
o Popular media may distort facts through omission of details
o In-depth research article becomes 30-second sound bite
Evaluating Information on the Internet
- There are no rules for posting on the Internet
- Consider the source
- Keep in mind the scientific method
- Be on the lookout for “junk science”
Leading Causes of Death
1. Heart disease*
2. Cancer*
3. Chronic lower respiratory diseases
4. Stroke*
5. Accidents
6. Alzheimer's disease
7. Diabetes (type II influenced by diet) *
8. Influenza and pneumonia*
9. Kidney Disease
10. Intentional Self-Harm
*Diseases caused by lack of Nutrients
- People who have low nutrient diets (low in protein) are at higher risks for disease
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Nutrition Guidelines: Tools for a Healthful Diet
Linking Nutrients, Foods, and Health
- Nutrition problems
- Nutrition guidelines aim to prevent both
o Undernutrition
 Poor health resulting from depletion of nutrients caused by inadequate
nutrient intake over time
o Overnutrition
 Long-term consumption of an excess of nutrients
- Not about weight, about nutrients
- Adequacy
o The foods you choose to eat provide all the essential nutrients, fiber, and energy
in amounts sufficient to support growth and maintain health.
- Balance
o A healthful diet requires a balance of a variety of foods, energy sources, and
other nutrients.
o Different sources of protein, etc.
- Calorie Control
o Choosing a diet that balances the calories you eat with the amount of calories
your body uses
o 2015 guidelines were first ones that included calorie intake*
- Nutrient Density
o Amount of vitamins and minerals relative to the calories the food provides
o For each calorie being consumed you are maximizing nutrients
- Moderation
o Not too much or too little
- Variety
o Include a lot of different foods in your diet
- In the US guidelines are updated every 5 years
- Fiber guidelines haven’t changed in a long time
Dietary Guidelines
- Intended to help improve overall
- Simple, easy-to-understand statements about food choices, food safety, and physical
activity
- Used to
o Develop educational materials
o Aid policy makers in designing and carrying out nutrition-related programs
- Dietary guidelines are important for populations but need to be modified per individual
Dietary Guidelines for Americans
- Cornerstone of federal nutrition policy and education
- Five overarching guidelines*
- Key Recommendations for the Dietary Guidelines for Americans
o Provide further guidance on how individuals can follow the five guidelines
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Five Overarching Guidelines ***
1. Follow a healthy eating pattern across the lifespan
2. Focus on variety, nutrient density, and amount
3. Limit calories from added sugars and saturated fats, and reduce sodium intake
4. Shift to healthier food and beverage choices
5. Support healthy eating patterns for all
Key Recommendations
- Follow a healthy eating pattern that accounts for all foods and beverages within an
appropriate calorie level*
- Consume less than 10 percent of calories per day from added sugars*
- Consume less than 10 percent of calories per day from saturated fats*
- Consume less than 2,300 milligrams per day of sodium
- If alcohol is consumed, it should be consumed in moderation—up to one drink per day
for women and up to two drinks per day for men—and only by adults of legal drinking
age*
- Meet the Physical Activity Guidelines for Americans*
o 30 mins in shorter than 10 min bouts
Foods to eat more of:
- A variety of vegetables from all of the subgroups—dark green, red and orange, legumes
(beans and peas), starchy, and other types
o Eat the rainbow
- Fruits, especially whole fruits
- Grains, at least half of which are whole grains*
- Fat-free or low-fat dairy, including milk, yogurt, cheese, and/or fortified soy beverages
- A variety of protein foods, including seafood, lean meats and poultry, eggs, legumes,
and nuts, seeds, and soy products
- Oils
o Minimize oils, avoid trans fat
Food to limit:
- Saturated fats and trans fats
- Added sugars
- Sodium
Level of Energy Intake
- Low: 1,400
- Moderate: 2,000
- High: 2,800
Portion Distortion
- Perception that large portion sizes are appropriate
- Contributes to positive energy balance, leading to weight gain over time and ultimately
may result in obesity
- Problem in Western Countries
Recommendations for Nutrient Intake: The DRI’s
- Dietary Reference Intakes (DRIs)
o Current dietary standards (sets of recommended intake values for nutrients)
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o Tells us how much of each nutrient we should have in our diets
o Includes Estimated Average Requirement (EAR), Recommended Dietary
Allowance (RDA), Adequate Intake (AI), and Tolerable Upper Intake Level (UL)
- Estimated Average Requirement (EAR)
o Nutrient intake level estimated to meet the needs of 50 percent of the
individuals in a life-stage and gender group
- Recommended Dietary Allowance (RDA)
o Nutrient intake level that is sufficient to meet the needs of 97–98 percent of the
individuals in a life-stage and gender group
o 2 Standard Deviations from E.A.R. on bell curve
- Adequate Intake (AI)
o Based upon expert estimates of nutrient intake by a defined group of healthy
people
o Set when not enough scientific data to set an EAR
 Based on ‘best estimate’
- Tolerable Upper Intake Level (ULs)
o Maximum level of daily nutrient intake that poses little risk of adverse health
effects to almost all of the individuals in a defined group
o where a nutrient can become toxic
The Dietary Reference Intakes
- Estimated Energy Requirement (EER)
o Intake predicted to maintain energy balance in a healthy adult of a defined age,
gender, weight, height, and level of physical activity
o Calories you should be consuming to maintain a healthy weight
- Acceptable Macronutrient Distribution Ranges (AMDRs)
o Amounts of macronutrients needed to provide adequate intake of essential
nutrients while reducing the risk for chronic disease
Food labels
- Food labels have five mandatory components:*
1. A statement of identity/name of the food
2. The net weight of the food contained inside of the package, not including the weight
of the package
3. The name and address of the manufacturer, packer, or distributor
4. A list of ingredients in descending order by weight
5. Nutrition information
a. Calories per serving
b. Fat
c. Carbohydrates
d. Added sugars
- Above the black line is mandatory information
Nutrient Content Claims
- Regulated by the Nutrition Labeling and Education Act (NLEA) and FDA
- Have made an effort to use meaningful terms
- Have reduced the number of potentially misleading label statements
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Health Claims
- Link one or more dietary components to reduced risk of disease
- Must be supported by scientific evidence
- Approved by FDA
- For a Specific disease
o Ex: Improves osteoporosis
Structure/Function Claims
- Describe potential effects on body structures or functions, such as bone health, muscle
strength, and digestion
o General statement, NOT a specific disease and does not need to be approved
by FDA
 Ex: Improves bone health
- Must be related to the food’s nutritive value
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Chapter 4: Carbohydrates: Simple Sugars and Complex Chains
What are carbohydrates?
- Sugars, Starches and Fibers
- Main food sources: *
o Plants
 Produced during photosynthesis
- Two main carbohydrate types
o Simple (sugars)
o Complex (Starches and Fibers)
 Starches: how plants store glucose
 No glucose gained from eating animals because after an animal
dies glucose becomes unstable
 Fiber: non-digestible carbohydrates
Simple Sugars
- Monosaccharides (individual units of sugar: CH2O)*
o Glucose
o Fructose
o Galactose
 Enzymes split the bonds and give us these monosaccharides
 This is what we absorb, end of digestion
- Disaccharides: Consist of two monosaccharides linked together
o Sucrose: glucose and fructose
o Lactose: glucose and Galactose
o Maltose: glucose and glucose
 What we can digest, breakdown and absorb
Monosaccharides
- Glucose
o Most abundant simple sugar in nature
o Also called dextrose****
o Gives food a mildly sweet flavor
o Usually joined to another sugar in foods
o Provides energy to body cells
 Body closely regulates blood sugar levels
Glucose and fructose
- Fructose
can be used for energy
o Also called levulose or fruit sugar*
o Tastes the sweetest of all the sugars
o Occurs naturally in fruits and vegetables
o Found in fruits, honey, and corn syrup
o Can be used for energy by the body but only in Emergencies *
 Given enough time fructose is converted into glucose
- Galactose
o Rarely occurs as a monosaccharide in food
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o Can not be used directly for energy must be converted to glucose in liver
o Usually bonds to glucose to form lactose
 Primary sugar in milk and dairy products
Disaccharides
- Sucrose: glucose + fructose
o “Table sugar”
o Made from sugar cane and sugar beets
o Listed as sugar on food labels
- Lactose: glucose + galactose
o “Milk sugar”
o Found in milk and milk products
o Lactose intolerant don’t have the enzyme needed to break down lactose
- Maltose: glucose + glucose
o “Malt sugar”
o Seldom occurs naturally in foods
o Product of starch breakdown
o Found in germinating cereal grains
o Found in fermented things like beer
Complex Carbohydrates
- Chains of more than two monosaccharides
- Oligosaccharides
o Three to ten sugar molecules
o Examples of sources: dried beans, peas, and lentils
- Polysaccharides
o Long chains of monosaccharides
 Longer than 10
o Structural differences affect how they behave in water and with heating
o Digestible or non-digestible
- Starch (polypeptides)
o Plants store energy as starch
o Found in grains, legumes, and tubers (potatoes and yams)
o Long chains of glucose units
 Amylose—unbranched chains
 Amylopectin—branched chains
 EASIER FOR DIGESTION
o Resistant starch: A starch that is not digested
 Functions like fiber
 See fiber benefits
- Glycogen
o Living animals store carbohydrate* in the form of glycogen.
o Provides body glucose when blood glucose levels get low
o Highly branched chains of glucose units
 Easy for digestion
o Most stored in our skeletal muscle and liver
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o If blood levels go low liver will break down glycogen for energy
o Skeletal muscle storage is for flight or fight response
o Carbohydrate “loading”
 Works to extend endurance capabilities*
 Increases amount of glycogen in Skeletal muscle and liver
- Fiber
o Nondigestible carbohydrates and lignins
o Dietary fiber: Found in plants
o Fruits, vegetables, legumes, and whole grains
 Functional fiber: Isolated and added to foods
o Soluble fiber: dissolve in water
 Speed up digestion and absorption
o Insoluble fiber: does not dissolve in water
 Slows down digestion and absorption
o Need combo of both soluble and insoluble fibers
Types of Fiber
- Cellulose, Hemicelluloses, Pectins, Beta-glucans, chitin and chitosan
o Chitin is usually found in supplement form and advocated at weight loss
supplement
o Doesn’t actually do what it is advertised to do
Benefits of Fiber
- Hasn’t changed in nutrition guidelines, moderate to high fiber in diet
- Stabilizes blood cholesterol levels
o Fiber binds to bile and removes it from your body
- Delays stomach emptying so you feel full for longer
- The healthier your intestinal bacteria, the healthier you are
o Fiber helps keep intestinal bacteria happy
Carbohydrate Digestion and Absorption
- Digestion breaks down carbohydrates to single sugars
o Mouth
 Salivary amylase begins digestion of carbs
o Stomach
 Acidity of stomach juices halt action of salivary amylase and stops
carbohydrate digestion
 Mechanical breakdown still occurs
o Small intestine
 Pancreatic amylase continues starch digestion
 Brush border enzymes digest disaccharides to monosaccharides
o Other digestive enzymes
 Maltase – maltose: glucose and glucose
 Sucrase – sucrose: glucose and fructose
 Lactase – lactose: glucose and Galactose
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-
Bonds that link glucose molecules
o Alpha bonds (in digestible carbohydrates)
 Broken down by human enzymes
 Starch
o Beta bonds (in fiber)
 Bonds remain unbroken by human enzymes
 Cellulose
- Digestion
o Enzymes
 Highly specific
 Examples include lactase and Beano
 Some carbohydrates remain intact, such as fiber and resistant starch
- Absorption: The small intestine swings into action
o End products of carbohydrate digestion*
 Glucose
 Galactose  glucose
 Fructose  glucose
o Liver
 Stores and releases glucose as need to maintain blood glucose levels
Carbohydrates in the Body
- Glucose is our primary fuel
o Needed to burn fat efficiently
o When we eat food, our bodies:
 Immediately use some glucose to maintain normal blood glucose levels
 Store excess glucose as glycogen un liver and muscle tissue
- Using glycogen for energy
o Liver glycogen
 Maintains normal blood glucose levels
o Muscle glycogen
 Fuels muscle activity
- Sparing body protein
o Adequate carbohydrates prevent body from making glucose from body proteins
- Preventing ketosis
o Ketone bodies  ketosis  dehydration
o Body needs a minimum of carbohydrate/day to prevent ketosis
Regulating blood glucose
- To maintain an adequate supply for cells but not too much glucose
- Controlled by hormones released by pancreas
o Insulin (blood glucose is too high)
 Key “unlocking” body cells and allowing glucose to enter and fuel them
 Increase of glucose in cells and decrease in the blood
o Glucagon (blood glucose is too low)
 Breaks down glycogen to glucose
 Decrease of glucose in cells and increase in the blood
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o Epinephrine
 “fight or flight” hormone
 Epinephrine cases Gluconeogenesis: creating glucose molecules
from non glucose molecules
 Same effect as glucagon
- Too much glucose damages kidneys, eyes, can stop blood flow to certain areas and
attacks peripheral nervous system
- Glycemic index
o Foods vary in their effect on blood glucose levels
o Index measures the effect of food on blood glucose levels
o Helpful for people with type I diabetes
The role of Carbohydrates in our Diet
- Recommended Intake of Carbohydrates
o AMDR = 45–65 percent of kcal****
 Average American: 49-50 percent of kcal
- Dietary Guidelines
o “Reduce the intake of added sugars”
o AMDR for added sugars = < 25 percent of daily energy intake
o Choose whole grains, vegetables, fruits, and cooked dried beans and peas
o Consume > one-half of all grains as whole grains
- Thirteen percent of adults’ total caloric intakes come from added sugars.
o High soft drink consumption
o Milk, vitamin and mineral quality of diet is declining
- Choosing carbohydrates Wisely
o Increase fruit, vegetables, legumes, whole grains, fat-free or low fat milk
- Strategies
o Eat peel of fruit/vegetable
o Eat legumes
o Brown rice
o High fiber cereal
o Whole fruit/vegetables rather than juices
- Moderating sugar intake
o Use less added sugar
o Limit soft drinks, sugary cereals, candy, ice cream and sweet desserts
- Nutritive sweeteners (provide calories)
o Monosaccharides, disaccharides, and sugar alcohols
o Natural vs. refined
- Non-nutritive sweeteners (do not provide calories)
o Saccharin
o Aspartame
o Acesulfame K
o Sucralose
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Carbohydrates and Health
- Fiber and obesity
o Possible role in weight control
- Fiber and type 2 diabetes
o Better control of blood glucose
- Fiber and cardiovascular disease
o Can lower blood cholesterol levels
Negative health effects of excess fiber
- Gradual intake and increased water consumption
- Can bind small amounts of minerals
Health Effects of Sugar: Causation or Correlation?
- Sugar and obesity
o Excess energy intake—not sugar intake—is associated with a greater risk of
obesity.
- Sugar and Diabetes Mellitus
o High intake of carbohydrate or sugar does not cause diabetes.
- Sugar and Heart Disease
o Sugar by itself does not cause heart disease.
- Sugar and ADHD in Children
o Important to keep other environmental factors in mind when assessing the
relationship between high-sugar foods and behavior
Carbohydrates and Health
- Sugar and dental caries promoted by:
o Carbohydrate remaining in the mouth
 Food that sticks to teeth
o Frequent consumption
 Sip high sugar drinks over time
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Diabetes Mellitus
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Disorder of Carbohydrate metabolism
Type I
o Autoimmune disease
o Immune cells attack and destroy cells that produce insulin
o Insulin dependent diabetes
o Can be stimulated by some viruses
o Easier to treat
Type II
o Body produces insulin but cells do not respond to the insulin
o Insulin insensitivity
o Not insulin dependent
Gestational
o Looks like type II
o Only during the pregnancy then it resolves itself
o Baby produces cells that attack insulin
Pre-diabetes
o Starting to see insulin insensitivity
Blood Test levels for Diagnosing Diabetes
Type
Fasting Plasma glucose (mg/dL)
Diabetes
126 or above
Prediabetes
100 to 125
Normal
99 or below
Risk Factors
- Type I
o First degree relative with type I diabetes
o More common in Caucasians
- Type II
o Lifestyle risk factors
o > 45 yrs old
o Overweight
o Sedentary lifestyle
o More prevalent in minorities
Treatments
- Type II treated with lifestyle changes
o 10% of population with have type II no matter what lifestyle changes are made
o Type II can be “cured”
- Type I easier to be treated because cells are still reacting to insulin**