Week 1 Flashcards
1
Q
What is nutrigenomics?
A
This is a branch of nutrition in which an individual will respond uniquely to their nutrition status based on their genetic makeup
2
Q
What is a positive energy balance?
A
This is when an individual is consuming an excess amount of calories that exceeds their daily requirements and will result in the calories being stored as fats.
Seen in both macronutrients and micronutrients.
3
Q
Is a developed or developing country more likely to contain individuals in a positive energy balance?
A
Developed
4
Q
What does nutrigenomics question?
A
Nutrigenomics questions how much of a nutrients one should be consuming. This consumption would be based off of their genetic makeup. If they lacked excreted a micronutrients easier then most they may need to consume more to get the required amount.
5
Q
What is the definition of nutrition?
A
Nutrition is the science of food and food systems, their nutrients and other constituents, and how their interactions within and between all relevant biological, social, and environmental systems.
6
Q
What are the 5 perspectives that make up nutritional sciences?
A
- Broad and integrative discipline (uses different studies)
- Strives to achieve a comprehensive understanding
- Researches the process by which we consume food
- Holistic approach
- It is the basis for formulation and dissemination
7
Q
What is an essential nutrient?
A
An essential nutrient is a nutrient that is unable to be synthesized at the rate necessary or at all that will allow for optimal health and must be consumed in one’s diet.
8
Q
What two observations need to be made for nutrients to be considered essential?
A
- When ones diet is deficient in the nutrients it causes an alteration in ones biochemical processes and results in symptoms which illustrate the decline in someones health.
- When the nutrients is restored in ones diet the dietary problems correct their selves and no permanent damage has occurred.
9
Q
If a pregnant mother is deficient in iodine what condition develops in the child and will the introduction of iodine in the child’s diet after birth correct the problem?
A
This will lead to the development of cretinism which is permanent and can’t be corrected.
10
Q
What does a deficiency in Iron, Folate, or Vitamin B12 cause?
A
Anemia.
Anemia causes low oxygen levels as the amount of red blood cells in the body are decreased.
In development this will decrease growth and cognitive impairment.
Can cause fatigue
11
Q
What does a deficiency in Vitamin D cause?
A
A deficiency in vitamin D causes rickets or osteomalacia.
This will result in deformed leg bones during infancy and fractures in adults.
Vitamin D is 10% diet and 90% sunlight.
Low levels have been linked to cancer, multiple sclerosis and cardiovascular diseases.
12
Q
What does a deficiency in Thiamine (Vitamin B1) cause?
A
A deficiency in thiamine causes beriberi which causes there is abnormalities in one’s nerves, weakness and pain in limbs and irregular heartbeat. Also impairs energy production.
13
Q
What does a deficiency in Vitamin C cause?
A
Causes scurvy due to a lack of fruits and vegetables. Will prevent proper collagen formation which causes haemorrhaging, bleeding gums and and skin ulcers.
14
Q
What does a deficiency in Niacin (vitamin B3) cause?
A
Causes Pellagra. Due to a corn-based diet which is characterized by sensitive skin, dementia and diarrhea.
15
Q
What are nutrient requirements?
A
These are considered frequency distrubutions
16
Q
Nutrient requirements are considered ________ of nutrients needed by individuals ________ to achieve a similar endpoint
A
Frequency distributions, within a population
17
Q
To make nutritional requirements what do nutritional scientists need?
A
- Data on the number of nutrients required to satisfy an endpoint
- The percentage of a population that requires a similar amount of nutrients.
18
Q
What is an Estimated Average Requirement?
A
the amount of nutrients required to meet the needs of 50% of individuals within a population
19
Q
What is the Recommended Daily allowance?
A
The recommended daily allowance is 2SD away from the EAR and is the amount of a nutrients an individual needs to consume. Consumption of the RDA means there is 97.5% chance you are not deficient in the nutrients. The other 2.5% of individuals maybe deficient as a result of their genetic material.
THE INTAKE THAT WILL MEET THE NEEDS OF 97.5% OF INDIVIDUALS WITHIN A POPULATION.
20
Q
What are some impacts of vitamin D deficiency?
A
Vitamin D deficiency reduces the amount of vitamins circulating the body. Low levels of vitamin D in the blood reduces calcium stores. Low levels of vitamin D causes a reduction in calcium stores which can lead to a low bone density causing rickets (abnormal bone development) and an increase in fractures in adults (osteomalacia). Likewise, it can also impair vision.
21
Q
Why do we not set the RDA higher then 2SD above the EAR?
A
This does not happen for two reasons.
- The RDA can be achieved through a diet of whole foods. Higher than 2SD above the EAR could require the intake of supplements.
- An RDA higher could cause toxic effects.
22
Q
What is an issue with having to high of vitamin D?
A
This will increase calcium stores which can cause calcium crystallization in soft tissues like the kidney (kidney calcification) and increases calcium in the blood.
23
Q
What is the Tolerable Upper Intake?
A
This is the maximum amount of a nutrients that should be consumed over long periods of time. An intake greater over long periods of time can have negative effects.
24
Q
What is the goal of health Canada?
A
The goal of health Canada is to keep the whole population between the RDA and the UL. The ratio between individuals at the UL and RDA is known as the therapeutic index.
25
How do you calculate the therapeutic index?
TI = UL/RDA
26
What is the Al and when do we use it?
This is the acceptable intake that is used when we do not have the data to set an EAR or RDA. This is the average intake of individuals who appear healthy and meeting the nutrients requirement. This is usually what is used when the nutrients deficiency does not pose a high risk.
27
What is the EER?
The EER is the estimated energy requirements. This is the amount of energy one should consume to maintain a balanced and healthy weight. This is determined by one's age, sex, gender, physical activity, height and life stage.
28
What does the EER include for children and pregnant women?
The EER takes into consideration the amount of energy that is needed for growth.
29
The Acceptable Macronutrients Distribution Range is....
The amount of each macronutrients that should be consumed of a particular energy (protein, fats or carbohydrates). This amount will help prevent chronic diseases while providing adequate intakes of essential nutrients.
30
What diseases can insufficient macronutrients cause?
This can cause protein/calories or protein/energy malnutrition which can cause a wide spectrum of wasting and stunting conditions
31
How many essential nutrients are there?
There are 40 essential nutrients out of 5000 nutrients
32
What does the food composition analysis refer to?
Food composition analysis refers to the development, application, and study of analytical methods for characterizing food and their constituents
33
What are the three food composition analyses that are used in foods and animal feeds?
Proximate analysis, newer methods, and Southgate analysis.
34
What is the proximate analysis?
The proximate analysis is the basic determination of a foods moisture, crude fibre, crude fat, crude protein and ash (mineral) content.
35
What is the newer methods?
The newer method replaces or extends components of the proximate analysis (aka. more detailed information can be provided from using this method)
36
What is the Southgate method?
The Southgate method refers to the analysis of crude fiber for carbohydrates, allowing researchers to determine the amount the fibre, starch and sugar content of foods.
DOES NOT DETERMINE THE AMOUNT OF SOLUBLE OR INSOLUBLE FIBRE THERE IS.
37
Why should there be standardized qualifications for food?
1. To allow for manufactures to know if their food is safe, desirable, healthy and for quality control.
2. Prevents companies from making false claims about their products or branding the product as something it is not
3. Helps reduce competition between food companies. To illustrate if a food product does not contain a certain value for its ingredients it is not actually able to be labelled as a product
4. Allows for there to be information for nutrition labels, ingredient lists, and health claims.
38
What 6 things are on the nutrition facts of a food product?
1. Serving Size
2. Serving per container
3. Amount per serving
4. Calories
5. Vitamins and minerals
6. Percent Daily values
39
What does it require to determine the trans fats in foods?
It requires gas lipid chromatography and thin-layer chromatography
40
Why are trans fats used?
trans fats are used to increase the shelf life of the product and taste and are cheaper to use.
41
Are all foods created equally? If not explain how?
Not all foods are created equally. Some foods have a greater nutrients density than others. For example, the amount of nutrients a cupcake provides in comparison to broccoli is much lower. Likewise, the number of calories in a cupcake compared to broccoli is much greater. Thus, it is not very nutrient-dense. A cupcake would have a low nutrients density or empty calories.
42
What is the general framework for proximal analysis?
The general framework for proximal analysis is composed of 5 parts.
1. The moisture is determined by weighing food before and after it has been dried out. This difference will tell you the amount of moisture in the food
2. The crude protein (nitrogen the Kjeldahl Analysis)
3. Crude fat (ether extraction)
4. Crude fiber (Southgate)
5. An atomic spectrum of ASH content
43
True or False?
| To determine the minerals, crude protein, crude fat and crude fibre the food needs to be wet.
False, in order to determine the crude fat, crude protein, crude fibre, and minerals you need the food to be DRY.
44
True or false?
| Food goes bad quicker when its dried and dried food does not impact the taste or appearance of the food.
False, dried food spoils over a longer period of time than wet food. Dried food can alter the taste, texture and apperance of the food.
45
How do researcher determine the crude fat of food?
The crude fat of protein is determine by using an ether extraction. Ether contain lipid like substances and are non-polar so will carry lipid substances out of a food.
Ether extractions do not determine the phospholipid, triglycerides, fatty acids and cholesterol content just the lipid content.
46
How do researchers determine the mineral content of foods?
| Why is knowing the minerals important?
Minerals are inorganic compounds and do not dissipate in fire. That is why to determine minerals the dry food is burned and the ash represent the mineral content of the food.
The mineral content of food is important because it can help enhance the flavour, the shell life, appearance and texture of the food. Some minerals like sodium in large qualities can impact ones health and thus regulating minerals and informing consumers of mineral content in products can help.
Can help inform manufacturers and consumers about how long it will take for microorganism to grow on food
Can impact physiochemical properties (how fast bread will rise)
The nutritional fact label of products needs to include iron, calcium and sodium so knowing these mineral values of very food is essential and mandatory.
47
What minerals are mandatory on nutritional labels?
1. sodium
2. calcium
3. iron
48
How do researchers determine crude protein?
Crude protein is determine through the use of nitrogen. This method is known as the Kjeldahl method.
49
What is melamine and why is it bad?
Melamine is added to foods to elevate the protein content of foods. However, melamine is high in nitrogen and when used in feeds in high qualities it causes kidney failure.
50
How do researchers determine the crude fibre content?
The crude fibre content is organic matter that is indigestible and is typically added to feeds to bulk them up (think more cow feces would be better but this is not allowed as the amount of fibre is regulated) . This is carefully regulated by government officials to ensure that waste products are not added to products to increase the fibre content.
The Southgate analysis is used to determine the starch, fibre and sugar content of CHO in the food. The Southgate analysis is unable to differ fibres (insoluble and soluble) and would require the use of gas chromatography.
51
Do nutrition labels state the fibre, sugar and starch content?
No the nutrition labels only state the total carbohydrates, sugars and fibre. To determine the starch content one must subtract the fibre and sugar from the total CHO on nutrition labels
52
Why is the proximal analysis not being able to separate soluble and insoluble fibre an issue for farmers trying to determine the amount of energy their animals are consuming?
Some animals are able to digest and absorb insoluble fibres and some can NOT and as a result the amount of energy that a species can consume from their feed may vary, for that reason some animals could consume to much or to little energy.
53
What are the three insoluble fibres?
Insoluble fibres are cellulose, hemicellulose and lignin
54
What are the three soluble fibres?
pectins, gums and mucilages
55
Does proximal analysis look at digestibility or bioavailability?
No the proximal analysis does not look at digestibility or bioavailability.
56
What determines the bioavailability of food?
The bioavailability of food digestibility is determined by the digestive tract of the species. This is why knowing if a species can digest insoluble fibre which can contribute to the amount of energy a species is consuming is necessary.
57
Is the serving size based on the wet food or dry food?
The serving size is based on wet food not dry food. It includes the moisture content of food.
58
How are iron and calcium derived to be placed on the nutritional label?
It needs an atomic absorption spectroscopy of the Ash fraction which is done when doing a proximal analysis of the food.
59
Where is the caecum located in humans and what is it called?
The caecum in humans is located in the large intestine and is called the appendix and it contributes to fermentation and gut immunity.
60
where is the urine and feces of birds collected
the cloaca
61
What is the diet like for species with a non-functional cecum (like humans who's caecum is small, the appendix)
Very nutrient dense food (this is food that contains a high amount of essential nutrients which are nutrients required for optimal metabolism) and low fibre
62
What is a non-functional caecum referred to as?
Vestigal
63
What is one link to the benefits of the appendix (small caecum)?
There is a high concentration of immune cells in the tissues and microbes found inside the appendix
64
What is a chronic disease that can evolve after removing the appendix?
Irritable bowel syndrome
65
What does the appendix provide to the colon after a food poisoning event or infectious diarrhea?
microbes. microbes use the appendix as a "safe house" and when the microbes in the colon are lost they can go and be transferred there.
66
Is the luminal content of food considered the inside or outside?
The luminal content is considered the outside as absorption must transfer the nutrients across the mucosal cells, into the blood then the tissue.
67
What are the two enzymes secreted from the salivary glands in the oral cavities
alpha-amylase (starch) and lingual lipase (fats)
68
What does the breakdown of carbohydrates in the oral cavity help increase....(think taste)
The breakdown of carbohydrates in the oral cavities through the secretion of alpha amylase is the increase in sweetness
69
Does the enzymes released in the oral cavities, alpha amylase and lingual lipase, help or impact digestion significantly?
No it does not impact digestion significantly and individuals who do not have proper enzyme excretion in the oral cavities do not have impacts in digestion.
70
What part of the digestive system is the acidic compartment?
The stomach, has a pH of 2
71
How many sphincters are there? What are they?
There are two sphincters the opening or entrance which is the lower esophagus sphincter and the exit which is the pyloric sphincter.
72
What is the pH in the stomach?
The pH in the stomach is 2 and the low pH in the stomach is what allows for food to be broken down and converted into chyme. Also, the acidic concentration denatures the proteins releasing fat into droplets that are able to move down the GI tract
73
What do the gastric gland secrete?
The gastric glands secrete water, HCl, enzymes, mucus and electrolytes
74
What is the stomach empty and filled?
The stomach empty is 50 mL and filled is 1-1.5 L
75
How long does it take the stomach to empty?
2-6 hours
76
Why is acid secretion important in the stomach?
The acidic secretion in the stomach is important as the acidity allows for proteins to be denatured. The denaturing and degrading of proteins allows for the release of some of the fats stored or captured within the proteins.
77
How are the fats released from the proteins in the stomach due to acid secretion?
The proteins release fats into little droplets to be released in the GI tract.
78
What are the two enzymes that are secreted in the stomach to begin the breakdown of the proteins consumed in the diet?
The two enzymes that are secreted is pepsin and parapepsin.
79
What is two of the functions of the acidic content of the stomach?
This is to breakdown proteins and denature them to help with digestion and releasing the fats into droplets. Likewise, the acidic content helps kill and remove any bacteria that was ingestion which could be harmful.
80
What makes the four regions of the stomach differ despite there being no real distinct separation?
The secretion and the inner surface
81
What is the cause of heart burn?
When there is excess secretion of acid or improper closure of the lower esophageal sphincter the acid content can move up the esophagus causing the heartburn feeling.
82
What is gastro-esophageal reflux disease (GERD)?
When the lower esophageal sphincter does not close properly or there is constantly an excess of acid causing inflammation of the esophagus this can lead to GERD (gastro-esophageal reflux disease)
83
What is symptoms which follow when the pyloric sphincter does not close properly and the acidic content of the stomach exits through the improper closing and enters the small intestine?
This causes nausea and vomiting as well as heartburn.
84
When in the GI tract do we see reverse motility and why?
We see reverse motility in the GI tract when the stomach and the esophagus expel food upwards as this is done to remove food that is sensed to be toxic.
85
What is gasteroparesis?
This is improper closing of the pyloric sphincter of the stomach which causes acidic content to enter the small intestine which cause heartburn, vomiting and nausea.
86
When Chyme leaves the stomach it is acidic what changes the acidity in the small intestine?
The bile secreted from the liver , the pancreatic juices and duodenum secretion
87
From what are the digestive enzyme mainly secreted from in the small intestine?
The pancreatic juices
88
Can humans survive without gallbladders?
Yes
89
What is the second brain?
The enteric nervous system
90
What are the reverse waves called in the small intestine?
The reverse waves in the small intestine are called the impeding waves.
91
What triggers the impeding waves in the small intestine?
The second brain aka the enteric nervous system will be informed by the receptors in the small intestine that there is nutrients which has not fully been digested (digestion is not completed). If something is not fully digested it can not be fully absorbed so it will cause the impeding waves to go and move food back to the beginning of the small intestine where digestion is a lot higher/greater. Also if a nutrients hasn't been absorbed a lot and can be absorbed greater then it will be sent back to the beginning of the small intestine for absorption.
92
What causes the small intestine to have bidirectional movement of food?
The impeding waves which are caused through the detection of the receptors in the small intestine which detect if further digestion can occur and if so will send the notification which causes the second brain (aka the enteric nervous system) which triggers the impeding wave (reversing the motility)
93
Why is the enteric nervous system unique compared to the other nervous systems?
It has complete reflexes and does not require the use of the brain or spinal cord
94
Why are the receptors in the small intestine significant for macronutrient absorption?
The small intestine receptors are significant for macronutrient absorption because they detect how much bile for example or pancreatic secretion needs to be released for optimal digestion.
95
Why is there cross talk between the enteric nervous system and the central nervous system?
To allow for optimal metabolism by discussing hunger cues and hunger controls. This allows for whole body energy metabolism as systems are coordinated.
For example: when you are digesting foods you are not also hungry.
96
What causes the small intestine to be 40 m^2?
The several levels of the anatomical and cellular structures.
97
How many levels of the small intestine are there?
There are four levels of the small intestine
98
What are the four levels of the small intestine?
1. Kerckring folds
2. Villi
3. Microvilli
4. Glycoproteins.
99
Explain the four levels of the small intestine?
1. Kerckring folds are visible to the human eye and is the folding of the small intestine (helps with the 40 m^2 surface area). These foldings give the wrinkly appearance of the small intestine.
2. The villi. The villi surround the kerckring foldings are are composed of the capillary bed, venue, arteriole and the central lacteal. The villi keep their shape through the extracellular matrix proteins and the outer epithelial cell layer called the enterocytes. The enterocytes need to be replaced every 3 days and are replaced by the crypts which are at the bases of the villi through cell division
3. Microvilli. The microvilli are found on the villi and are finger like projections which are composed of membrane bilayers.
4. Glycoproteins. Glycoproteins are a mesh layer which surround the microvilli. This layer extends/reaches out into the lumen and acts as a binding site for digestive enzymes so they are not lost when moving past. The digestive enzymes they catch are made right by the transporters.
100
What replaces the outer epithelial cell layer of the small intestine of the villi?
At the cyrpts which is at the base of the villi will repair the epithelial cell layer which helps maintain the shape of the villi. The outer epithelial layer unlike the other layer (the extracellular matrix proteins) needs to be replaced every 3 days. This replacement is done through the stem division at the crypts, with the stem cells differentiating close to the top where enterocytes are needed..
101
What does a villi need to contain?
A villi needs to contain central lacteal, arteriole, venule and capillary bed
102
What maintains the structure of the villi?
The extracellular matrix proteins and the outer epithelial cellular layer (enterocytes)
103
Is there more bacterial cells or human cells in the body?
There are more bacteria cells (500 colonic bacterial cells)
104
What weighs more bacteria or human cells?
Human cells.
105
Do bacterial cells require oxygen or not to grow. What type would this be anaerobic or aerobic?
Bacterial cells do not require oxygen to grow. This is anaerobic bacteria.
106
Are babies born with colon microbes?
No babies are not born with colon microbes but colonization of these microbes occur rapidly.
107
Do the microbe population diversity increase or decrease with age?
Microbe population diversity decreases with age and as chronic diseases occur
108
What are 6 of the things that microbes can do for our health?
6 things microbes can do for our health is
1. Ferment undigested fibre
2. Ferment resistant starches
3. Ferment proteins
4. Produce VFA which provide energy
5. Help displace pathogens
6. Help with transit time reducing constipation
109
What do colonic microbes produce and do we absorb this product or not?
Colonic microbes produce violate fatty acids (VFA) which can be used for anaerobic metabolism (no oxygen)
110
What are the three types of VFA that are produced by the microbes in the colon?
Acetic acid, butyric acid, and propionic acid
111
What type of digestive systems do humans, dogs, cats and pigs have?
Simple system with a non-functional or small caecum
112
What is the key difference between pseudo-ruminants and true ruminants?
Hindgut fermentation
113
In pseudo-ruminants where is the caecum located and what is it?
The caecum is located in connection with the large intestine and is a large blind sac.
114
enzymes are _______?
Proteins. These enzymes can contribute to the protein content that is in the urine which can make it appear that some food have a low digestibility.
115
What are the two methods used to determine the digestibility of foods?
The two methods that are used to determine the digestibility of foods are the total collection method and the indicator marker.
116
How does the endogenous secretions impact the accuracy if the apparent digestibility?
Secretions in the body to help digest, metabolize and absorb food can all impact the digestibility of food. Enzymes are proteins so when we look at the apparent digestibility of a protein in the feces for example it can be greater then it truly would be because the enzymes are released into the feces but do not contribute to the true protein digestibility. Likewise, bacteria in the body can produce vitamins like boitin which can increase the amount of vitamin content present in the feces.
117
What are two other reasons (besides protein) apparent digestibility may not be accurate?
The apparent digestibility looks at the fece intake which can contain dead matter from the body such as enterocytes which can add to the weight of the feces. Bacteria that grows inside the human can increase the bulk of feces, like vitamins which can make it look like more nutrients was absorbed than really was
118
What is the difference between apparent digestibility and true digestibility?
Apparent digestibility does not account for how fece matter can be bulked up and can make it look like poorer digestibility of a feed but true digestibility takes into account these differences as it determines the endogenous secretions and removes these from the feces.
119
What factors impact digestibility?
Feed intake (more digestion when food is restricted)
Particle size (faster particles pass quicker)
Chemical composition (cooking a meal can change the composition and digestion)
Geography (higher altitudes more retention)
Age of animal
120
Are the enzymes that sit in the lipid bilayer proteins?
Yes, these are proteins that sit in the membrane bilayer to help facilitate diffusion.
