Midterm 1 Flashcards
Distinguish between the terms: food, nutrient, and nutraceutical
food- pshycological, social, culteral, economic and technological factors effecting food choice
nutrients- balance (ESSENTIAL)
nutraceuticals- not required (health promoting)
What are the differences between and the origins of hunger and appetite
hunger- physiological (low blood glucose)
appetite- psychological (response and desire to food), triggered by hunger
What do we mean by the term satiety in the context of food consumption, and why is it an important concept to study
feeling of being full (fats) which slow down rate of stomach emptying and fibres which increase stomach and SI content viscosity
important due to the rise in obesity
List the regions of the digestive tract and indicate their functions
1) mouth- produce bolus (saliva, amylase, enzymes)
2) stomach- chyme- destroy microorganisms, pepsin- breakdown large food molecules, churning and mixing
(none to little absorption)
3) small intestine- duodenum: releases pancreatic fluid and intestinal juices, jejunum: emulsifies fats by bile, breakdown fats, proteins, carbs; assimilation begins, Ileum- assimilation continues
4) large intestine: site of fermentation (colon- water reabsorption, mineral reabsorption and microbial fermentation, detox and protection) (rectum- water reabsorption and stool evacuated)
Why is digested food first acidified in the stomach and then neutralized in the small intestine?
digested food is acidified in stomach to destroy microorganisms and then neutralized in the small intestine so that enzymes can function
pepsin vs. trypsin
pepsin (peptic enzymes)- in stomach start to breakdown are food molecules
trypsin (proteases)- in duodenum of SI, enzyme induced breakdown occurs by hydrolysis
Why does a high fat meal leave a feeling of satiety longer than a high carbohydrate meal?
fats are digested slowly, carbs are digested quickly
role of liver
- secretes bile to SI to neutralize stomach acid
- accepts nutrients from hectic portal vein
- carb AAs metabolism
role of gall bladder
stores bile from liver
role of pancreas
secretes enzymes and bicarbonate ions to SI for neutralizing stomach acid and enzyme induced breakdown (hydrolysis)
- secretes insulin and other hormones for regulation in body with hormonal control
kidney
absorption and excretion
Lipids and sugars are absorbed differently by the body. Why?
lipids are fat soluble and sugars are water soluble
Describe the fate of lipids, sugars and amino acids after ingestion
lipids go to the lymphatic system which takes fat soluble compounds from GI tract through thoracic duct to bloodstream
sugars and AAs are taken by blood vessels to the liver
Why does a high protein meal put more load on the kidneys than a high fat meal?
because fats just get stored as body fat but proteins replace body protein and then they end up as nitrogen lost in urine and excreted by kidneys
When we discuss “optimal” nutrient intakes, what are we “optimizing” for? How difficult are each of these goals to achieve?
refers to optimizing to
- prevent deficiencies
- maintain healthy weights
- optimize health and delay degenerative disease
difficult to achieve due to difficulty determining biological requirements due to individual variations, lack of food consumption data, human studies restricted and expensive
How many servings of each of the four food groups in Canada’s Food Guide should YOU consume?
Adult (19-50) female veg. and fruits 7-8 grain products 6-7 milk and alternatives 2 meat and alternative 2
What are some of the main “eating right” messages of Health Canada?
- increase fruits & vegetables (especially fruits),
- increase fibre,
- eliminate trans fat,
- reduce saturated fats,
- reduce total fats,
- include a small amount of polyunsaturated fat,
- reduce simple sugars,
- increase calcium,
- reduce energy intake,
- drink water,
- include folic acid, iron (for mature women), vitamin D (over 50s)
- increase physical activity!
Why recommend to Canadians that they should choose a variety of foods from each food group each day?
- balanced diet
- helps maintain a healthy, well balanced, interesting diet that provides adequate nutrition
- can help prevent diseases
What is meant by the “metabolic syndrome”?
refers to combination of factors that greatly increased a persons risk of developing cardiovascular disease
What is the definition of EAR, RDA and AI? How are the numbers determined and by whom?
EAR- estimated average requirements: median required for specific age and gender groups
RDA- recommended dietary allowance: EAR and 2 standard deviations to cover 97-98% of population (specific to age and gender)
AL- adequate intake: when no EAR exists
Howis the % daily value on the Nutrition Facts table calculated?
%daily value= actual content in the food per serving/ reference daily intake
How is the energy content of a food serving, which is declared on a food label, calculated?
found by thermic effect of food avg physiological food values: carbs 16 MJ/kg protein 15 fat 37 ethanol 29 *multiply these values by the % of each and multiply by grams
What does (the abbreviation) BMR mean and what is it?
basal metabolic rate- 60- 70% or more of daily energy
- the use of energy to maintain body function at rest, most accounted for by organs and muscle
- increase with activity
- decrease when energy intake remains below needs for long
- increased during overconsumption (thermos genesis)
What does EER mean and what is it? What is your EER?
estimated energy requirement: 2 standard deviation rule not applied
What does BMI mean and what is it? How is it calculated? In terms of BMI, what is considered normal? Obese? What is your BMI?
Body Mass Index: weight/ height2
normal (18.5-24.9)
obese 1 (30.0-34.9)