UNIT 1: INTRODUCTION Flashcards
The science of food and food systems, their nutrients and other constituents, and their interactions within and between all relevant biological, social, and environmental systems
Nutrition
What is an essential nutrient?
- chemical required for optimal metabolism
- cannot be synthesized (or rapidly enough) to meet physiological function
What are the 2 steps to determine if nutrient is essential?
- remove from diet, and is deficient
2. put nutrient back in, and it corrects the problem (refeeding stage varies depending on pathology)
Deficiencies in thiamine (vit B1) is…
lethal
Deficiencies in folate is…
suboptimal
Deficiencies in B12 is…
suboptimal
Deficiencies in vitD is…
suboptimal
Deficiencies in vit C is…
lethal
Deficiencies in niacin (vit B3) is…
lethal
Approx. how many essential nutrients are there?
a. 4
b. 10
c. 40
d. 400
~ 40 essential nutrients
- classified by chemical structure, absorb/digest//transported, impact on health
Define EAR.
EAR - estimated average requirement
- Recommended intakes to maintain optimal health in population.
- Calculated by taking average/mean of population (peak)
How much of the population will have a higher nutrient requirement than EAR? How much will have lower?
50% higher and 50% lower.
- the EAR is the average
What is the RDA?
RDA - recommended daily allowance
- add 2SD to the mean
RDA = EAR + 2SD
- this will include 97.5% of the population
If the whole population consumes RDA level of nutrients, will there people who are deficient? What proportion?
2.5% deficiency
At what point does conc. of nutrient become “excess”? What is this called?
Upper limit. (UL)
Past the UL the condition level is considered suboptimal.
At what point is nutrient considered suboptimal?
- past UL
- less than EAR
The highest average daily intake that may not pose a risk of adverse effects to most individuals in population is…
UL - upper limit
~3.5-4 SD above EAR
Health Canada tries to keep the whole population between which two points?
RDA - recommended daily average and upper limit (UL)
What is the therapeutic index?
TI = UL / RDA
It measures the difficulty in accomplishing the goal of keeping the whole population between RDA and UL
The dietary reference intake that is derived for nutrient if EAR and RDA evidence is insufficient is called…
Adequate Intake
- AI indicates more research needs to be determined with a certain degree of confidence
The dietary reference intake that is the average dietary intake predicted to maintain energy balance in healthy normal weight individuals is…
Estimated Energy Requirement (EER)
- defined by age, gender, weight, height, level of physical activity
The dietary reference intake for the intake range for a particular energy source (protein, fat, carb) expressed as a percentage of total energy (kcal) that is associated with reduced risk of chronic disease while providing adequate essential nutrients is….
Acceptable macronutrient distribution range (AMDR)
RDA is used to calculate energy requirements.
True or False
False.
Nutrient requirements, not energy.
- this would lead to obesity and recommended daily intake covers 97.5%
What is used to correctly determine energy requirements?
EER - Estimated Energy Requirement.
- factors in age, body weight, gender, height, level of physical activity
In adults, rank macronutrient AMDR of fat, carbs, protein in increasing order of contribution to total daily energy.
- Protein 10-35%
- Fat 20-35%
- Carbohydrates 45-65%
What is energy expenditure = ?
resting metabolism + physical activity
PCM and PEM are due to?
insufficient macronutrients
- protein/calorie malnutrition
- protein/energy malnutrition
Name the macronutrient classes.
- carbs
- lipids
- proteins
Name the micronutrient classes.
- vitamins
- minerals
Which classes of molecules/nutrients are organic?
- carbs
- lipids
- proteins
- vitamins
Both macronutrients and micronutrients contribute to growth and development, but are consumed in ____
macro - consumed in large amounts
micro - consumed in smaller amounts
Macro or micro:
- metabolic regulation at level of gene expression and hormonal control
micronutrients
Macro or micro:
- support metabolism and physical activity in calories
macronutrients
What is your body composition?
- 55-65% water
- 20-25% lipid
- 15% protein
- 2% vitamins/minerals
- 0.5% carb