nutrition
The adding back of some of the nutrients to grains whose levels decrease as a result of the refining process came from concerns for the health of Americans during WWII Folate was added in 1998 because of its role in preventing neural tube birth defects
Federal Enrichment Program
Tuberous vegetables Cereal grains (corn, wheat, rye, barley, oats) Rice Legumes Nuts, seeds
Naturally occurring dietary sources:
Both types of fiber may prevent or reduce the risk of constipation and conditions associated with it because fiber (indigestible) creates bulk in the large intestine and helps to stimulate peristalsis which helps with regularity. They also prevent obesity because both types of fiber help fill up the stomach which increases satiety, and decreases the total number of calories consumed. Soluble fiber in particular delays stomach emptying because it has gel forming characteristics.
significance of fiber
proteases
digest proteins, synthesized in the stomach, pancreas, small intestine, functions in the stomach and small intestine
Total calories are calculated using the carb value which includes fiber even though fiber does not contribute to the calories
explain carbohydrate components on a food label
They provide energy during the process of germenation
explain how plants might use simple sugars and complex carbohydrates (why fruits are sweet and seeds are starchy)
hydrochloric acid
facilitates digestion process in the stomach, functions in the stomach
bile
facilitates the digestion process, synthesized in the liver, stored in the gal bladder, functions in the small intestine
bicarbonate
facilitates the digestion process, synthesized in the small intestine
a. Sweet --> carbohydrates (energy) -->seek b. Sour--> spoiled food (bacteria) --> avoid c. Salt→ sodium--> seek d. Bitter--> might be toxic/poisonous→ avoid e. Umami→ (savory) protein (glutamate)--> seek f. TASTE-->SURVIVAL
10. Describe the role that taste plays in the digestive process and in health more generally
a. Variety of factors can affect the rate at which the stomach contents empty into the small intestine (WEIGHT CONtROL) b. Presence of fat or protein in meal→ delay stomach emptying ( make sure fat and protein in every meal) c. large meals= quicker release into small intestine (eat smaller meals or smaller portions) d. liquids leave stomach faster (Don't drink your calories) e. carbs release first, then protein and fat (we want some fat and protein in every meal) f. takes about 20 mins for brain to recognize what we have eaten... need brain to catch up (eat slower, enjoy meal)
11. List the factors that can affect the rate of stomach emptying and predict how that could affect total calorie intake
a. MOUTH: Mechanical breakup of food via teeth and tongue to facilitate swallowing; saliva lubricates food to help with swallowing, amylase helps digest carbs, contributes to taste; detection of food's taste b. Esophagus moves food to stomach via peristalsis (NO DIGESTION OR ABSORPTION) c. Stomach has chime that has digestive juices and denatures protein d. Small intestine is the primary site for digestion and absorption: neutralization of acidic chime from stomach with bicarbonate; emulsification of lipids via bile salts; release of amylases, proteases, and lipases; mixing chime with bile and digestive enzymes via longitudinal and circular muscles to complete the digestion of carbs, proteins, and fat... absorption of nutrients and other food components and reabsorption of digestive secretions through intestinal villi e. Large intestine: controls the release of waste; bacterial activity (prevents pathogenic bacteria from growing, helps maintain a healthy colon by producing by-products that the colon can use for energy, produce some vitamin K that can be absorbed from the colon, produce gas); reabsorption of water and absorption of some minerals and vitamin K
12. Match the mouth, esophagus, stomach, small and large intestine with the digestive and/or absorptive activity(ies) that take(s) place there
a. Saliva--> carbohydrates b. Digestive enzymes on carbs, fats, and proteins c. HCl --> break down contents of stomach d. Bicarbonate neutralizes HCl e. Bile
13. Match the digestive chemicals saliva, and the digestive enzymes, hydrochloric acid, bicarbonate, and bile with the compounds upon which they act and/or their function
a. Make calories more prominent b. Provide information on added sugars c. Change the micronutrients to reflect those of current public health significance i. Remove A and C, add D and potassium, include absolute amounts d. Change the footnote regarding the "Percent Daily Value" for better clarity E. Change serving sizes to reflect the amount that is actually eaten
5. Compare and contrast the components of the new and old Nutrition Facts labels
Once compounds have entered the intestinal villi cells (they line the walls of the small intestine & absorption and reabsorption can take place up and down each one), they are then deposited into either the CAPILLARIES OF THE CIRCULATORY SYSTEM or the LACTEALS OF THE LYMPHATIC SYSTEM. Water soluble compounds enter via the capillaries of the circulatory system and fat soluble compounds enter via the lacteals of the lymphatic system.
15. Distinguish between the roles that the circulatory and lymphatic symptoms play in the absorptive process
Small intestine can control amount of absorption of SOME micronuts but it varies based on the amount of micronut you ate. But efficiency of macronut (protein, carbs, fat) digestion and absorption is ALWAYS GREATER THAN 90% regardless of how much macronut you ate. ANATOMY OF GI TRACT MAXIMIZES CHANCES THAT MACRONUTS WILL BE DIGESTED AND ABSORBED BC THE MOUTH, STOMACH, and SMALL INTESTINE PRODUCE AMYLASES, PROTEASES, and LIPASES TO DIGEST AND ABSORB MACRONUTS.
16. Compare the efficiency of macro and micronut absorption and explain why the difference exists
Mouth prepares for food in cephalic phase (i.e. saliva and other shit) and prepares rest of GI tract via taste and smell and begins digestion of carbs w amylases. Stomach begins digestion of protein with proteases Small intestine emulsifies fats with lipases and does a lot of mixing with longitudinal and circular muscle movement and has high surface area for absorption (⅓ football field) and blood supply can be diverted to intestinal villi to maximize nutrient uptake 30 other digestive enzymes also facilitate this and 10 different hormones and other regulatory chemicals produced by GI tract work to increase muscle activity, movement of food material, and open and close the sphincters.
17. List the ways by which the GI tract maximizes efficiency.
Poop is made out of... Undigested food (primarily fiber) Shedded/extra intestinal cells MOSTLY dead bacteria To poop: The excretion of waste from the GI tract requires sufficient bulk pressing against the walls of the colon to stimulate peristalsis & sufficient WATER for lubrication and softening
18. List the components of fecal matter and explain what the excretion of waste from the GI tract requires.
Friendly bacterial strains live on undigested material (primarily FIBER) in the large intestine and THESE BACTERIA... prevent pathogenic (BAD) bacteria from growing, producing extra stuff the colon can use as energy, produce VITAMIN K that can be absorbed from colon, and produce gas which is the only bad thing.
19. List the roles that bacteria plays in health.
a. Digestion- The chemical breakup of complex food molecules (the macronutrients) into molecules small enough to be absorbed b. Absorption- the process of bringing those small molecules, along with the micronutrients, and other food components INSIDE the body
2. Define digestion and absorption
a. To represent those of current public health significance b. Remove vitamin A and C, adding vitamin D and potassium, including absolute amounts
2. Explain why the micronutrients labels were chosen
A PRObiotic is a bacteria-containing food or supplement (Activia yogurt or like physical probiotic pills). A PREbiotic is the "food" that bacteria live on (found in fruits and veggies and whole grains and fiber).
20. Explain the difference between a probiotic and a prebiotic.
Indigestion ----> HEARTBURN Indigestibility ----> INABILITY TO DIGEST (Also called Non-Digestion) Many fad diets and supplement products confuse indigestion with the inability to digest.
21. Explain the difference between INDIGESTION and INDIGESTIBILITY and how it relates to claims associated with fad diets and supplemental products.
Disease that limited esophageal function: since no digestion or absorption happens here, the food would literally just move slower towards the stomach (peristalsis would be affected) Disease that limited stomach functioning: not enough HCl secreted into stomach could affect pH level which could lead to increase in microorganisms Disease that limited stomach functioning part 2: not enough HCl could also limit the process of denaturation of protein and cause the small intestine to work harder when finishing protein digestion with proteases Disease that limited stomach functioning part 3: if the sphincter between the stomach and small intestine that is supposed to release contents teaspoons at a time was either limited or releasing too much at once, the efficiency of the digestive and absorptive process in the small intestine would not be maximized OR weight control would be affected Disease affecting pancreas: bicarbonate and macronut-digesting enzymes could not be released properly from the pancreas, leading to effects in the small intestine where the majority of digestion and absorption takes place that needs these enzymes. Disease affecting liver: Bile not released properly from liver, affecting emulsification of lipids and possibly affecting the gallbladder which is where bile is stored. Digestion of macronut could possibly not be completed in the small intestine because of this. SOMEONE WHO NEEDS TO BE TAKING DIGESTIVE ENZYME SUPPLEMENTS MIGHT BE UNDERWEIGHT (i.e. CYSTIC FIBROSIS)
22. Predict the consequences of a loss of functioning of a component or components of the GI tract or organs associated with it (i.e what would happen relative to nutrient digestion or absorption if you had a disease that limited the functioning of your pancreas, liver, stomach, etc.).
FOOD COMBINING: theory of eating that claims that certain foods should not be eaten together because of the body's inability to digest them simultaneously. INACCURACY: thinking that eating a steak (which has protein that requires HCl in the stomach to break it down) and a baked potato (which needs an alkaline in the stomach to break it down) neutralizes the stomach acid because an an acid and an alkaline is typically thought to neutralize. THIS IS FALSE. INACCURACY: thinking that more digestive juices have to be secreted into the stomach because of this and thinking that they continue to become neutralized... FALSE Beverly Hills Diet misconception that food combining leads to food not being properly digested leading to excess weight HOWEVER no digestion = no absorption = no calories = NO WEIGHT GAIN!!! You will lose weight if you follow these fad diets that limit food combining because you would be restricting your calories
23. Identify and explain the inaccuracies related to digestion and absorption found in popular fad diet plans that focus on the principle of FOOD COMBINING.
LIVER (Post Absorption): screens and begins to metabolize unwanted compounds that small intestine let in & converts wanted compounds into other compounds (i.e. converts fructose into glucose and/or fat). KIDNEYS (last stop): excrete absorbed but unwanted WATER SOLUBLE compounds like excess water soluble vitamins & excrete water soluble waste products of metabolism like urea from excess protein & control nutrient levels by increasing or decreasing excretion as body needs (i.e. water, sodium, potassium, electrolyte balance). !!!YOU WOULD FIND SOME OF THE EXCESS WATER-SOLUBLE VITAMIN C THAT YOU CONSUMED IN UR PEE!!! This is an example
24. Explain the roles that the liver and kidneys play in processing and/or eliminating absorbed compounds.
Bran (outer covering)- rich source of niacin, thiamin, riboflavin, magnesium, phosphorus, iron and zinc; contains most of the seed's fiber Germ (plant-to-be)- concentrated source of niacin, thiamin, riboflavin, vitamin E, magnesium, phosphorus, iron, and zinc. The germ also contained protein and some healthful unsaturated fats The endosperm, which makes up the bulk of the gran, is all that remains after refining. It contains the majority of the grain's protein and carbohydrate, but only small amounts of vitamins and minerals.
3 parts of a grain kernel
a. Longitudinal muscles- shorten and lengthen the tract to create a wave of movement b. Circular muscles- opens and closes to work with the longitudinal muscles and propel things through the tract and out of the tract
3. Compare and contrast the roles that longitudinal and circular muscles play in the movement of food material along and out of the GI tract
a. Pancreas makes proteases, amylases, lipases, and bicarbonates b. Gallbladder makes bile
4. Describe the roles that the pancreas and gall bladder play in the digestive process
a. Longitudinal muscles and circular muscles work together to move food along, and ultimately out, of the GI tract b. The contraction of circular muscles behind the food material prevents it from going backwards, while "waves" of longitudinal contractions act to propel it forward
4. Explain peristalsis
a. 5% of daily value is low b. 20% is high
4. Read and interpret a food label, for example, by determining whether something is a good or not so good source of a nutrient
a. Sphincters are a type of circular muscle that acts as a valve to control the movement of the food material from organ to organ so as to maximize both the digestive, as well as the absorptive process b. Sphincter at the esophagus and the stomach- prevents backflow of food into the esophagus c. Sphincter at the stomach and small intestine- limits the rate of flow into the small intestine d. Sphincter at the small and large intestine- limits the rate of flow into the large intestine e. Anal sphincter- controls the elimination of waste from the body
5. Explain structures, function, and location of the sphincters
a. ENZYMES b. Proteases- digests proteins; synthesized in the stomach, pancreas, and small intestine; functions in the stomach and small intestine c. Amylases- digests carbohydrates; synthesized in the mouth, pancreas, and small intestine; functions in the mouth and small intestine d. Lipases- digests fats; synthesized in the pancreas and small intestine; functions in the small intestine e. OTHER DIGESTIVE CHEMICALS f. Hydrochloric acid- facilitates the digestive process; synthesized in the stomach; functions in the stomach g. Bicarbonate- facilitates the digestive process; synthesized in the pancreas; functions in the small intestine h. Bile- facilitates the digestive process; synthesized in the liver, stored in the gallbladder; functions in the small intestine
6. List the 6 chemicals or types of chemicals involved in digestion and identify their functions, sites of synthesis and sites of action
a. TRUE i. Raw foods contain enzymes that can "digest" the macronutrients within plants (papaya contains proteases) ii. Heating food destroys enzymes (denaturing of muscle protein during cooking makes it easier to chew) b. FALSE i. Eating foods without enzymes makes digestion more difficult (we make PLENTY of digestive enzymes on our own) ii. Lack of digestion causes obesity (if we lack both our digestive enzymes and plants, we would be absorbing less calories and losing weight)
7. Provide a critique of the claims made by proponents of the raw food diet
a. BEFORE FOOD ENTERS THE MOUTH b. Cephalic phase- brain is thinking about the food (taste, small, look, saliva forms, stimulus, and gastric secretions c. Prepares the GI tractà maximize efficiency of digestion and absorption d. Cooking- soften tissues: connective tissues in mean and fibrous tissues in plants e. Cooking increases the variety of foods we can eat and the variety increases the likelihood that we get all the essential nutrients which improves the likelihood of survival
8. Describe the roles of the cephalic phase and cooking play in digestion
a. Cutting incisors of a rodent, pointed canines of a carnivore, and grinding molars of an herbivore
9. Explain how our teeth reflect our being omnivores
Excess insulin production in response to carbohydrate intake Causes blood and glucose drop rapidly and or too low
Causes of hyperglycemia
polysaccharides
Complex Carbohydrates →
a. The food label tends to encourage avoiding foods vs selecting foods based on nutrients of need
Describe the implications associated with the design of the food label relative to how people might view food (and what makes up a "healthful diet") more generally
-lactose is digested by lactase (enzyme) and absorbed as glucose and galactose -sucrose is digested by sucrase (enzyme) and absorbed by glucose and fructose
Di:
low in fat - contains carb foods that have vitamins, minerals and dietary fiber - monitor total carb intake by carb counting or another way - be consistent in amount of carbs consumed at meals and snack
Dietary Recommendations type 2
a. All packages food is regulated by the FDA- except anything covered by USDA or ADF b. All packaged foods must carry a nutrition information panel c. % of the daily values are based on 2000 calories d. with some exceptions, all the nutrients may be added at the discretion of the manufacturer i. for micronutrients, only vitamin A and C, and the minerals calcium and iron are required e. 5% of daily value is low (bad if it is a good nutrient that you want, good if it is not healthy) f. 20% is high g. all ingredients must be listed in descending order by weight, aka the first ingredient is the one that is present in the largest amount h. manufacturers are allowed to round down to 0 when a value is .5 grams or less i. FDA regulates (ultimate approver) the use of reduced, free, light, more, less, low calorie i. Light mayo is half the amount of calories as regular mayo, and reduced fat has half as many as the light j. There are government defined serving sizes, but they may not be the amount that you eat k. FDA decides what claims can be made
Explain the basic regulations governing food labels, including: the ingredient list, rounding; the use of descriptive terms; serving sizes; health claims
known as "fruit sugar" May be used for energy Some may be converted to glucose by the liver Excess fructose can be converted to fat in the liver Fruits and vegetables and honey (as a monosaccharide) Sucrose-containing (as a part of a disaccharide) Fiber-containing foods (as a part of a polysaccharide)
Fructose:
NA Some may be converted to glucose by the liver Limited (as a monosaccharide) Lactose-containing foods (as a part of a disaccharide)
Galactose:
known as "blood sugar" and "dextrose" Can be used by any type of cell for energy Brain and central nervous system use almost exclusively for energy (is critical) Excess can be converted to fat in the liver Fruits and vegetables and honey (as a monosaccharide) Lactose-containing foods and sucrose-containing foods (as a part of a disaccharide) Starch-containing foods and fiber-containing foods (as part of a polysaccharide
Glucose:
Sugar is essential in the gelling process of jams, preserves and jellies to obtain the desired consistency and firmness. This gel-forming process is called gelation, where the fruit juices are enmeshed in a network of fibers.
How are sugars used in food processing
Sources: wheat bran, whole wheat products, legumes, nuts, fruits, vegetables Characteristics: does not dissolve in water; small amounts can be digested by intestinal bacteria
Insoluble fiber
Also known as "milk sugar" - a disaccharide of glucose and galactose Milk (mammalian) and its products
Lactose:
Glucose absorbed as glucose Fructose absorbed as fructose Galactose absorbed as galactose
Mono:
Starches are digested by amylases (enzymes) and absorbed as glucose Fiber is NOT digested therefor all dietary carbohydrate is absorbed in the form of monosaccharides
Poly:
monosaccharides and disaccharides
Simple Sugars
Sources: oat bran, oat products, legumes, fruits, vegetables Characteristics: does dissolve in water (will form gels); slows the rate at which the stomach empties; larger amounts can be digested (fermented)by intestinal bacteria, as compared to insoluble fiber May help to prevent obesity, control blood glucose levels , and lower serum cholesterol levels
Soluble fiber
Polysaccharides (1000s) of GLUCOSE only
Starches
sugar=sucrose; we have enzymes that break down sucrose into glucose and fructose Bees collect nectar (sucrose) from plants; they have enzymes that can breakdown sucrose into glucose and fructose- a disaccharide of glucose and fructose Our body sees these as the same thing!!
Sucrose is often seen as "bad", while honey is seen as "good"
Also known as "refined sugar", "white sugar", "table sugar", and is "sugar" on a food label Fruits and vegetables
Sucrose:
fructose, sucrose, glucose, galactose, and lactose
Sweetness from greatest to least:
not significant in "the trapper" because binding is in milligrams and what we consume is in grams If the fat trapper really did trap significant amounts of fat in the GI tract preventing its absorption and aiding in weight loss then would have oily stool
Using a soluble fiber supplement
Increase fiber intake SLOWLY to give your GI tract time to adjust DRAIN and RINSE canned beans before using Rinse dry beans several times; do not use rinse water in cooking Use BEANO to digest the gas-causing indigestible carbohydrates in beans and other vegetables. It can be added to food (via drops)or taken by mouth before the meal via a tablet
Ways to reduce discomfort (gas) associated with high-fiber vegetable and legume consumption:
a. Esophagus; pathway to the stomach, food moves through peristalsis b. Stomach; holding tank for several hours c. large intestine; holding tank, stores/controls the release of waste d.small intestine; primary site of absorption and digestion
Which organs are part of the GI tract and which are related to its function
They cause rapid weight loss Most of this is water from urine You can eat lots of typically forbidden foods You don't feel as hungry You have limited choices No eating high calorie junk food and no drinking large quantities of high calories soft drinks and other sugared beverages Give you an excuse not to eat vegetables Told that you don't have to exercise Any restricted eating plan can cause weight loss because it tells you what and when to eat
Why did carbohydrate restricted diets become so popular? Because they work over the short term. How?
Typically 10s-100s of GLUCOSE, FRUCTOSE and/or other monosaccharides The bond makes fibers different from starch
basic structure of fiber
Pancreas stops producing insulin due to an autoimmune response The body's immune system attacks its own insulin likely due to an environmental trigger such as a virus There is a genetic predisposition Can occur at any age but most commonly develops in childhood
causes of (type 1) hyperglycemia
Causes: - cells respond less well to the presence of insulin which is called insulin resistance -associated with abdominal obesity - strong genetic predisposition
causes of (type 2) hyperglycemia
Using a cellulase supplement→ not beneficial because we are losing the benefit of fiber You would take the cellulose (indigestible) and you would be breaking it down and increasing the number of calories consumed You may also see an increase in constipation Using a soluble fiber supplement→ not significant in "the trapper" because binding is in milligrams and what we consume is in grams If the fat trapper really did trap significant amounts of fat in the GI tract preventing its absorption and aiding in weight loss then would have oily stool
consequences of using a cellulase supplement, and a soluble fiber supplement that binds to dietary fat and explain why
analyses
digest carbohydrates synthesized in the mouth, pancreas, and small intestine
Realized the complexity of the molecule was not the most important factor in determining rate of digestion
history and development of the Glycemic index
Inulin Oligofructose Polydextrose Modified wheat starch Soy fiber Sugarcane fiber Health benefits specific to soluble fiber require that the fiber be vicious. Most of the soluble fibers like inulin are not
how can manufacturers add fiber to foods what is it and their healthfulness compared to whole fiber sources
Make sure the word "whole" is in front of a grain identified first on the label's ingredient list It must say 100% whole grain Dark or brown bread does not mean grain
how can u know something is for sure whole grain
Have different thickening and gel-forming characteristics that are due to differences in: The number of glucose molecules in the starch The degree of "branching" of the molecule Glucose molecules can be arranged in a linear or branched formation
how do starches differ from one another
feeding 10 or more healthy people a portion of the food containing 50 grams of digestible (available) carbohydrate and then measuring the effect on their blood glucose levels over the next two hours.
how is gi determined in individual food
smaller, more frequent meals w fat and protein and moderate rise in glucose level
how to prevent hyperglycemia
too much
hyperglycemia
low in fat - contains carb foods that have vitamins, minerals and dietary fiber - monitor total carb intake by carb counting or another way - be consistent in amount of carbs consumed at meals and snack
hyperglycemia (type 1) dietary rcmdations
-low levels or no lactase production→ decreased or no digestion of lactose in the small intestine→ undigested lactose travels to large intestine Symptoms: -undigested lactose attracts water in the large intestine causing bloating and diarrhea -undigested lactose is metabolized by intestinal bacteria in the large intestine causing gas Who will experience it: -non caucasians because in their traditional meals there is not a lot of dairy -the elderly because lactase levels decline with age How to handle it: -eat foods naturally low in lactose -foods with lactase -small amounts of lactose containing foods with other foods
lactose intolerance, what it is, symptoms, who will experience it, and how to handle it
For men: It is recommended that they consume 35g/d of fiber For women: It is recommended that they consume 25 g/d of fiber Americans are only consuming 10-15 g/d
levels of fiber intake that are recommended by the DRIs and explain why americans are/are not close to meeting those goals
the GI is created by feeding a set amount of one food and monitoring changes in blood glucose -we don't always eat food by itself -we don't necessarily eat the amount of food used in the glycemic index test -the lists vary widely depending on the source of the data
limitations of GI
The primary function of carbohydrate in the body is to provide energy in the form of glucose. DRI for total carbohydrate consumption: 45%-65% of total calories To make sure not only that we get enough glucose for the brain and CNS, and during exercise, but also because foods naturally rich in carbohydrates are excellent sources of a variety of micronutrients and fiber as well DRI for added sugar: less than 25% of total calories Restricting added sugars is designed in part, to restrict foods that are nutrient poor
primary function of digestible carbohydrate in the body, list the DRI for total carbohydrate consumption, and for added sugars, and explain the rationale for each
A way to compare different foods' effects on blood glucose level
purpose of the glycemic index
Glycogen is a highly branched polysaccharide of glucose molecules -the function is a muscular response that stores energy to be used in fight or flight and is a quick source of energy vs fat stores
structure of glycogen and how it is used in the body
- excessive urination and thirst because the body is having to eliminate excess glucose - weight loss
symptoms of (type 1) hyperglycemia
develops gradually - few outward symptoms examples are tiredness and nighttime urination
symptoms of (type 2) hyperglycemia
It will convert to glycogen or convert to fat
two potential fates for glucose if it isn't used immediately for energy
Studies show that weight loss can be greater at 6 months for people on an Atkins-style diet as compared to those on a more traditional low fat/high carb diet BUT the difference in weight loss typically disappears after one year.
why do carb restricted diets work better for the short term, is there evidence to show that it works for the long term?
Because there are not many outward symptoms -rates are rising because -effects: Blindness from glucose induced nerve damage in the retina Amputations from glucose induced nerve damage which decreases awareness of injury which can lead to infection Cardiovascular and kidney disease from glucose induced blood vessel damage
why does type 2 diabetes go unnoticed, why rates are rising and potential affects of this disease