What factors can influence your food choices?
-Social changes (Time shortage for Americans)
-Flavor, Texture, Appearance
-Routine and Habit
Definition of Hunger
The primary physiological drive to find and eat food, mostly regulated by internal cues to eat.
Definition of Appetite
The primary psychological (external) influences that encourage us to find and eat food, often in the absence of obvious hunger.
State in which there is no longer a desire to eat; a feeling of satisfaction.
The science that links food to health and disease. Including the process by which humans ingest foods.
Chemical substance in food that contributes to health, many of which are essential parts of a diet. Nutrients nourish us by producing calories to fulfill energy needs, materials for building body parts, and factor to regulate necessary chemical process in the body.
A substance that when left out of a diet leads to signs of bad health. The body either cannot produce this nutrients or cannot produce enough of it to meet its needs. Then if added back into diet before permanent damage occurs, the affected aspects of health are restored.
Six Classes of Nutrients
Three functional categories of nutrients
1. Provide calories to meet energy needs
2. Important for growth, development and maintenance
3. Those that act to keep the body functions running smoothly
Why is water a nutrient?
-Solvent, Lubricant, Vehicle for Nutrients and Waste, Regulates Temperature
How much water should the average man and woman drink a day?
Men: 3 liters a day
Women: 2200 grams
AKA: "Super Foods"
Are plant chemicals that are physiologically active compounds in food that provide benefits but are not essential nutrients.
What is a Calorie?
The amount of heat energy necessary to raise the temperature of one gram of water 1ºC
What is a Kcal?
How many calories per gram are there for Carbohydrates?
How many calories per gram are there for Protein?
How many calories per gram are there for Alcohol?
How many calories per gram are there for Fat?
What percent of U.S. adults are overweight or obese?
What fraction of children in the U.S. are overweight/obese?
Definition of Food Science
Discipline in which engineering, biological, physical sciences are used to study the nature of food and food processes.
Definition of Nutrition (as in the occupation)
The science of food, the nutrients and substances therein.
Food Plate categories
Grains, Proteins, Vegetables, Fruits, and Dairy
What are Macronutrients?
-Major form of fat in food, key energy source, fat storage in body
-Made up of fatty acids and gycerol
Saturated and unsaturated
Composed of the elements carbon, hydrogen, oxygen, and nitrogen.
Functions of Protein
Bone and muscle
components in blood, cells, membranes, enzymes, and immune system.
1 pound= how many calories?
If there are 15g of carbohydrates, how many calories in the food come from carbs?
What are the biggest issues with the American diet?
What percent of calories (energy) should come from Carbohydrates?
What percent of calories (energy) should come from Fats?
What percent of calories (energy) should come from protein?
High calorie content relevant to nutritional content (vitamins, minerals).
High levels of nutrient content (vitamins and minerals)
Metabolic needs are met
Depleted supplies of nutritional needs
Can cause stomach distress and toxicity
Measuring Nutritional Status: (ABCDE)
A. Anthropometric: Weight, height, waste cirumfrence
B. Biochemical: Measure of nutrients in blood or waste products
C. Clinical: Physical exam
D. Dietary: examine the diet (food record)
E. Environmental: living conditions, educational levels, where they were raised
Daily recommended income
Recommended daily allowance
Estimated energy requirment
General Food Label Requirments
-Product name, name and address of manufacturer, amount of product in package, ingredients in descending order by weight, a nutrition fact panel
What foods are food labels not required on?
Raw fruits and vegetables, fish
Food Labeling and Protein
Protein percent Daily Value does NOT have to be listed for those over age 4
-American have plenty of protein in their diets, and it is very difficult and expensive to measure
Two components closely regulated by FDA
2. Disease or Health related conditon
What is the problem with Dietary supplements?
They are NOT strictly regulated
-Quality control-unknown concentrations of active ingredients
-Unknown active ingredients
What are the three pieces to a healthy diet?
A single serving size cannot contain more than ___ grams of fat
A single serving size cannot contain more than ___ grams of Saturated fat
A single serving size cannot contain more than ___ grams of cholesterol
What changes to the food label are they trying to change?
Have total calories first
Make fonts more appropriate
Less focus on fat, but more focus on sugars
Double layer of lipid, carbohydrates, and protein
Control passage of substances
Fluid material within a cell
-Anaerobic, produces energy for the cell without oxygen
Major site for energy production
Aerobic (uses oxygen)
All cells EXCEPT red blood cells
Communication network, synthesis, detoxification, calcium storage
packaging site for proteins
Cell digestive system
Contain enzymes for digestion
AKA suicide bags
Detoxify harmful chemicals
form peroxides (H2O2)
Prevent peroxide build-up (catalose)
Not in Red Blood Cells
Genetic material DNA makes up the senses found on chromosomes
Direct protein synthesis and cell division
Mitochondria contain their own DNA
Four primary types of tissue:
Carrie blood into the heart on the right side
Bring blood out of the heart (left side)
Blood and Plasma
Carries oxygen and carbon dioxide
carries nutrients and waste products
Contains the portal veins
transports most fats after digestion
Important part of Immune system
Pick up fluids between cells and transports fluids back to the heart for the cardiovascular system
MOuth's job in digestion
Long muscular tube
connects the pharynx (throat) with the stomach
Prevents food from entering the trachea
Muscular contractions that move the food bolus along
Closes the opening of the esophagus to the stomach
Large muscular sac
can hold up to 4 cups of food
food is mixed with gastric juices
-Hydrochloric acid (HCL)
Chyme is formed
Mixture of food and digestive enzymes
Gastric Juices/ Stomach Acids
-Destroys activity of protien
-Activates digestive enzymes
-partially digests dietary protein
-Makes dietary minerals soluble for absorption
Cells producing the HCL (stomach acid)
Release the enzyme pepsinogen
-Zymogen: inactive form of an enzyme
Pepsinogen is activated to pepsin by HCL
10 feet long
MOST OF THE DIGESTION AND ABSORPTION OF NUTRIENTS OCCURS HERE
Located at the base of the stomach, controls the entry of chyme into the small intestine
Three sections of small intestine
The contraction that moves food along through the system
Lining of the small intestine
Cavity of the small intestine
Folded many times
contains villi (finger like projections to trap food particles and enhance absorption
increases surface area 600 times
New absorptive cells constantly being produced
-Due to acidity of substance coming from substance they only last a few days
Crypts produce new cells
Ways to absorb nutrients
High concentration to Low concentration
-Fats, water, and some minerals
Carrier protein drives nutrient through absorptive cells
Carrier protein AND energy drive nutrient through cells
-glucose and amino acids
Active cells engulf solid nutrients
Active cells engulf liquid nutrients
-Mucus lining protects from bacteria
-Very small amount of absortion
-strength of the immune system occurs here
-formation of fecies
-Bacterial population (important for health and breaking down fiber)
Rectum= collecting area for feces
Anus is the outer opening utilized for elimination of fecal matter
2 Anal Sphincters
-External- under voluntary control
-recycled by enterhepatic circulation
Bile used in the small intestine to emulsify fat (detergent affect to break up fat into small usable pieces)
-Insulin: regulates blood glucose storage
-glucagon: regulates glycogen storage
Pancreatic enzymes- for breaking down carbs, fats, and proteins
Bicarbonate- protects lining of small intestine (like baking soda)
protects lining of small intestine (like baking soda)
For breaking down carbohydrates, fats, and proteins
Humans have nutrient storage so we do not have to eat constantly.
Where is Fat stored?
Where is Carbohydrates stored?
Where is protein stored?
There is no true reserve
Changes in gene expression caused by other factors
Study of how food impacts health
(currently a one-size-fits-all approach is used, but that will/is change)
Nutritional diseases with a genetic link:
An open sore on an external or internal surface of the body, caused by a break in the skin or mucous membrane that fails to heal
Causes: H. Plyori (bacteria), smoking/anxiety/stress, Non steroidal anti-inflammatory painkillers)
-1/2 of adults are affected
treated w/ medication and diet
-ignoring normal urges
** DIETARY FIBER
-regular physical activity
-Irritate the intestinal nerve
-Draw water into the intestine
-Regular use is harmful
Swollen veins of the rectum and anus
Intense pressure and straining especially in butt area
Dietary recommendation: FIBER and fluids
Irritable Bowel Sydrome
Symptoms: cramps, bloating, increased frequency, diarrhea, constapation
25 million cases
Causes: altered intestinal peristalsis, decreased pain threshold, stress/anxiety
Treatment: Elimination diet, moderate caffine, Low-fat, small, frequent meals
Fluidity and frequency of evacuation
Generally lasts 1-2 days
Causes: infections, poorly absorbed substances, too much fiber, sugar alcohols
Treatment: Plenty of fluids
Causes: Cholesterol crystallizing in solid masses
-Being over weight
-losing weight rapidly
Symptoms: Upper right abdominal pain, gas, bloating, nausea, vomiting
Treatment: removal of galbladder
Allergic reaction to gluten
-Flattens villi in small intestine
-Limits absorption of nutrients
Treatment: elimination of wheat and rye in diet
Grain and Gluten
Wheat, Rye, Barley
-Oats are often contaminated in the field during harvest but does not contain gluten
-Mucous blocks pancreatic ducts
-Impaired digestion of carbs, protein, fat
because enzymes are not delivered to small intestibe
Treatment: replacement enzymes
Foods that provide healthy benefits beyond those supplied by the traditional nutrients they contain
Stage of a disease or disorder not severe enough to produce symptoms that can be detected or diagnosed
The study of how disease rates very among different population groups
Generally a fake medicine of treatment used to disguise the treatments given to the participants in an experiment
Use of animals to studydisease to understand more about human disease
An experimental design in which neither the participants nor the researchers are aware of each participants assignment or the outcome of the study until it is completed. An independent third party holds the code and the data until the study has been completed
Dietary reference intakes: term used to encompass nutrient recommendations made by the food and nutrition board of the national academy of science.
Balancing Calories to manage weight
Balance between calories consumed and calories expended determines weight
What claim is NOT FDA approved?
Structure/ function claims
The surface tissue that line the outside of the body and all external external passages within it
Protein tissue that hold different structures in the body together some body structures are made up of connective tissues- tendons, and cartilage connective tissue also forms part of bones and the non muscular structure of arteries and veins
a type of tissue adapted to contract to cause movement
Tissue composed of highly branched, elongated cells, which transports nerve impulses from one part of the body to another
A system of vessels and lymph that acceots fluid surrounding cells and large particles, such as products of fat absorption. Lymph eventually passes into the blood stream from the lymph system
Barrier to invading microorganisms
The way that genome is marked and packaged inside the cell nucleous
Inherited changes in gene expression caused by mechanisms other than changes in the DNA sequence
Found in ring structure
Major monosaccharide in the body
-In bloodstream (blood sugar)
-Breakdown of starches and sucrose
source of fuel for cells
-part of sucrose
-In fruit, honey, and high fructose corn syrup
-converted into glucose in the liver
Part of lactose
-converted to glucose in the liver
Two sugars bonded together
-Sucrose, Lactose, Maltose
glucose and fructose= table sugar
Galactose and glucose = milk products
Glucose and glucose= fermentation and alcohol
soluble or viscus- Functional or fermentable
-Found in all plants
-Increases fecal bulk
Storage form of carbohydrate for animals and humans
-Structure similar to amylopecton --> highly branched
-More sites for enzyme action
-Found in the liver and muscles
Do NOT provide calories
High-Fructose Corn Syrup (HFCS)
Made from cornstarch mixed with acid and enzymes
55% or 42%fructose with a balnce of glucose and water
-Very close to sucrose
-Sweeter then sucrose
-Improved shelf-stability and food properties
How does the American intake of sugar relate to the recommended amount?
Most of U.S. has too much sugar in their diets
What creates Carbohydrates?
6 carbon+6 water= glucose+ 6 oxygen
What is the basic unit of all sugar?
A carbohydrate made up of multiple units of glucose attached together in a form the body can digest (complex carbs)
Substance in plant foods not digested by the processes that take place in the stomach or small intestine. Adds bulk to feces.
The concentration of carbohydrates to alcohole, acids, and carbon dioxide without the us of oxygen
Long, straight chains of glucose units
A digestible branched chain type of starch composed of glucose units
Raises blood glucose quicker
Fiber added to foods that has been shown to provide health benefits
What is important to remember when looking at the percent of calories from carbohyrates?
The percent of calories from carbs is more important than the total amount of carbs in a food when constructing a healthy diet
Sorbitol, xylitol, Erythritol
-Has cooling affect in mouth
-Does NOT promote tooth decay
-Metabolizes more slowly than glucose- good for diabetes
-Can give you diarrhea
Alternative sweeteners in order of increased sweeteness
Digestion of starches/fibers in the mouth
Some starches are broken down to maltose by salivary amylase
Digestion of starches/fibers in the Stomach
Salivary amylase is inactive by strong stomach acids in the stomach, NO farther digestion occurs in stomach
Digestion of starches/fibers in the pancreas
Enzymes (amylase) from pancreas break down starch into maltose in the small intestine
What type of sugar do they measure sweetness with?
Sucrose (table sugar)= 1 in sweetness
Types of sweeteners
Brown sugar: molasses and sucrose
Turbinado: raw sugars
Maple Syrup: Mostly sucrose
Honey: fructose and glucose
Agave Nectar: (insulin and heat) mostly fructose, little glucose
Fruit Concentrates: Mostly fructose
What is the result of not eat enough Carbohydrates?
Your body will start to break down protein and will eventually result in loss of muscle
The condition of having high concentration of Ketone bodies and related breakdown products in the bloodstream and tissues
What helps regulate glucose levels?
-Insulin: A hormone produced by the pancreas which increases the synthesis of glycogen in the liver and the movement of glucose from the bloodstream into body cells
-Glucagon: A hormone that stimulates the breakdown of glycogen in the liver into glucose
-Epinephrine: a hormone aka adrenaline is released and various nerve endings in the body it acts to increase glycogen breakdown in the liver, among other functions
Process regualting blood glucose
1. elevated blood glucose
2. Pancreas releases insulin
3. Glucose transports into cells
4. Conversion of glucose into glycogen
5. Normalization of blood glucose
6. Low blood glucose
7.Pancreas releases glycagon
8. Breakdown of glycogen to glucose
9. Increased gluconeogenesis
10. Normalization of blood glucose
The blood glucose response of a given food, compared to a standard GI is influenced by starch structure, fiber content, food processing, physical structure, and macro-nutrients in the meal, such as fat.
*The likelihood of a food to raise your blood sugar*
Glycemic load (GL)
The amount of carbs in a serving of food multiplied by the glycemic index of that carb divided by 100.
(GI*Grams of Carbs)/ 100= GL
How dies fiber help with blood glucose levels?
Fiber has slow glucose absorption which better regulates glucose
What is the recommended about of fiber intake for men? and Women?
Men: 38 grams a day
Women: 25 grams a day
Problems with high-sugar diets
Type one Diabetes
Decreased release of insulin
Frequent urination and urine high in sugar
*Body stops producing insulin
*beta cells are destroyed
Type Two Diabetes
-Begins often after age 40
-Most common type
-The insulin receptors on the cell surfaces of certain body tissues becoming insulin resistant
-Often linked with obesity and can be reversed by weight loss
Low blood glucose thatfollows a meal high in simple sugars, with corresponding symptoms or irritability, headache, nervousness, sweating, confussion
Low blood glucose that follows about a day of fasting
A condition in which a person had poor blood glucose regulation, hypertension, increased blood triglycerides and other health problems, this condition is usually accompanied by obesity, lack of physical activity and a diet high in refined carbohydrates
What is the most popular, and oldest sugar substitute in North America?
Saccharine (Sweet 'N Low)
Where in the digestive tract is Tagatonise metabolized?
What is the minimum amount of Carbs a person should consume a day?
130 grams MINIMUM
What is the main fuel source for the brain and blood cells?
What happens with undigested Carbohydrates?
-Only minor amounts escape digestion
-Travels to colon
-Fermented by bacteria
-Acids and gasses produced
-May promote health of the colon
-Transform monosaccharide into glucose
-Release glucose back into the bloodstream
-Store as glycogen (or fat)
Why do Legumes give people Gas??
Contain high levels of two indigestible sugars
-Stachyose (Tetrasaccharide) & Raffinose
-Humans Lack the Enzyme that Breaks Down these Sugars
-Pass Through the Stomach and Small Intestine into the Large Intestine
-Gas-Producing Bacteria in the Large Intestine LOVE These Sugars and Metabolize Them –Producing Gas
Functions of Carbohydrates
-Supply energy to brain, Central nervous system, and RBC
-Protein sparing: uses carbs before protein
-Prevents ketosis: maintains acid/base
High blood glucose
Low blood glucose
Role of Liver
Regulates glucose that enters bloodstream
Role of the pancreas
-Release of insulin
-Release of glucagon
The synthesis of new glucose from non-carbohydrates precursors
-Protein used as fuel and not to build and repair tissues
-Amino acids taken first from blood then from muscles, heart, liver, kidneys...
During sedentary (low activity) what is used as a predominant energy source?
Blood Glucose Regulation
VERY TIGHTLY REGULATED
Develops during pregnancy
Usually goes away after baby is born
Develops after early childhood