Exam #4 Flashcards
Function of vitamins?
promote and regulate body processes necessary for:
- growth,
- reproduction,
- and the maintenance of health
Fat soluble vitamins
- Are stored in the body’s fat (adipose) tissue
- Remain in our system longer than water soluble vitamins
- Not readily excreted (can build up)
- Too much of these can lead to toxic levels (except vitamin K)
Water soluble vitamins
- Excreted/ Flushed out of body if not used… not toxic
- Exceptions are Vitamins B-6 & B-12 (May not be flushed…excess amounts are not healthy)
- Because of the body’s limited vitamin storage capacity… We need to consume appropriate amounts every day via food, or in supplement form
Meeting vitamin needs general guideline:
If the % Daily Value is 5% or less, the food is a poor source of the given nutrient
if it is 10 to 19%, the food is a good source
If it is 20% or more, the food is an excellent source.
How do you determine the exact amount of a vitamin in food?
Look up the daily value and multiply it by the daily % value on the label
Bioavailability?
the extent to which the body can absorb and use nutrients
Bioavailability of vitamins: (%, where, influence)
About 40 to 90% of vitamins in food are absorbed
Absorption occurs mainly in small intestine
Composition of diet and conditions in digestive tract influence vitamin bioavailability
Vitamin bioavailability is affected by?
a) Absorption
- Fat-soluble vitamins: need dietary fat
b) Transport in blood
- Water-soluble vitamins transporter - blood proteins
vitamins go directly from small intestine to blood
- Fat-soluble vitamins transporter - chylomicrons
pass through the lymph before passing into blood
c) Conversion of inactive provitamins (vitamin precursors) into active vitamins
General function of vitamins:
a) Promote and regulate body’s activities
Examples:
Vitamin A = vision and growth and development
Vitamin K = blood clotting and bone health
Vitamin B = act as coenzymes
b) Act as coenzymes
c) Act as antioxidants protection against free radicals
Free radicals
highly reactive atom or molecule that cause oxidative damage
steal electrons from other compounds, causing changes to structure and function
Antioxidant
destroy reactive oxygen molecules
Functions of vitamin C, E and provitamin A
are antioxidants that help protect us from oxidative damage.
Functions of vitamin A, B6, C, D and folate:
are needed for healthy immune functions.
Functions of vitamin B6, B12, K and folate:
Are needed to keep blood healthy
Functions of vitamin A and D
are needed for normal growth and development.
Functions of vitamin B6, B12 and folate
are important for protein and amino acid metabolism.
Function of vitamin A, C, D, K:
are needed for bone health
Function of the B vitamins thiamin, riboflavin, niacin, biotin, pantothenic acid, and vitamin B6
are needed to produce ATP from carbohydrate, fat, and protein.
Frozen, fresh and Canned foods
Frozen Foods:
Frozen in the field helps to minimize nutrient losses
Fresh Foods: How Fresh? truck delivery days on produce shelf time in your fridge
Canned Foods:
availability & Affordable
10 ways to get the most nutrition from your food
- Eat locally grown food soon after it’s been picked
- Soak, Chop, Crush, Blend
- Store fruits and vegetables the right way
- Eat most sources of water-soluble and heat-sensitive nutrients raw.
- Know which foods are best when cooked.
- Pair food strategically to maximize nutrient absorption
- Keep it Simple
- Don’t discount frozen foods
- If possible, try an animal source
- Monitor your tolerance
What soaking, shopping, crushing and blending of food does to it:
Cutting fruits & veggies - breaks down rigid plant cell walls
Crushing and chopping onion & garlic - releases alliinase (helps to form compounds to protect against disease)
Soaking grains & beans - reduces phytic acid (blocks absorption of iron, zinc, calcium and magnesium)
How to store fruits and vegetables
All vegetables – refrigerator (except root variety)
All fruit except berries - room temperature (no light)
All cut fruit and vegetables - airtight container with a squeeze of lemon juice
All herbs - chopped up and frozen
Heat breaks down vitamins?
B1, B5, C & folate
In the USA multivitamins account for almost one-sixth of all purchases of dietary supplements and __% of all sales of vitamin and mineral supplements.
($___ billion in 2014)
40%
5.7
Mineral functions
Contribute to body structures
Regulate body processes, water balance and energy metabolism
Affect growth and development through their role in the expression of certain genes
Act as cofactors needed for enzyme activity
To maintain health our body requires more than __ _______ from our diet.
20 minerals
Major mineral
Need more than 100mg/day
Sodium, potassium, chloride, calcium, phosphorus, magnesium, and sulphur
Trace minerals
Need less than 100mg/day
iron, copper, zinc, selenium, iodine, chromium, fluoride, manganese, molybdenum, and others
Iron functions
Transports oxygen in blood and muscles
Releases energy from cells
Fights fatigue & infection (immune system)
Red blood cell production
How much iron do you need? Deficiency symptoms
7-8mg/day males
12-18mg/day females
10-13mg/day teens
Fatigue, headaches, difficulty concentrating, anemia, low blood hemoglobin
Calcium functions
Bone and tooth strength & structure
Muscular contractions
Nerve impulse transmission
How much calcium do you need? Deficiency symptoms
Adults = 1000 - 1500 mg/day
Body absorbs 300-500mg per meal
Bone deterioration (Osteoporosis)
Potassium functions
Aids nerve impulses, muscle performance
Reactions that build protein
Water balance, functions in balance of intracellular fluid
How much potassium do you need? Deficiency symptoms
Adults = 4700mg/day
Leads to muscle weakness or cramping during exercise, dehydration, loss of appetite, irregular heartbeat
Sodium functions
Aids nerve impulses, Water balance
Functions in ion balance of extracellular fluid
How much sodium do you need? Deficiency symptoms
Adults = 1200 - 1500 mg/day
Try to stay under 2400 mg/day (about 2 teaspoons)
leads to muscle cramping during exercise Too much (more common issue)… leads to high blood pressure, calcium loss, water retention
RMR - resting metabolic rate
The energy required to maintain the body’s vital processes in the resting state
* Basal Metabolic Rate (BMR)
TEF - thermic effect of food
The energy required to digest, absorb, and store food
PA = NEAT + EA (Physical activity)
all activity or movement,
including “spontaneous non-exercise activity”
Set point theory
A weight-regulating mechanism (WRM) in the human body that has a setpoint
Controls appetite and amount of fat stored
Following weight loss, the body attempts to regain the lost weight
(each person has a set point of body fat — a genetic instinct to survival (what it determines as acceptable body fat % and tries to maintain) — hence the importance of promoting a healthy body weight for children)
Consequences of dehydration
Increases fatigue… impairment of motor skill control
Mental function is reduced… impairment of decision-making and ability to concentrate
Increased body temp (105 degrees F or 40.5 degrees C = heat stroke starts)
Elevates heart rate, blood thickens
Nitrates build up (dangerous levels) in the bloodstream
Kidney & brain damage (can even lead to seizures or death)
Hydration has what positive effects?
Better concentration and focus
Improves motor skill performance
Feel less fatigued … energy isn’t just from CHOs!
Keep heart rate and body temp in optimal zone
How much of our fluids come from foods and beverages?
60% from beverages
40% from food
Fluid loss and hydration needs are affected by
Genetics (body size, amount we sweat… different for each)
Fitness level (fitter people sweat earlier and > amount)
Environment (hot environment = more sweating)
Exercise Intensity (intensity up = more sweat = > fluid loss)
How much fluid is needed per hour of exercise?
0.5-1L
Active people can tolerate drinking ______ every ____ during exercise or competition
150-300ml
15-20mins
After exercise we tend to only replace ___ of sweat and fluid loss
30-70%
How do you know if you should use sports drinks?
Exercise involving very high sweat rates
Exercise involving high intensity or long duration
Exercise involving hot and/or humid conditions
To speed up recovery after exercise
Water is the best replacement fluid during exercise? T or F
No flavour
Turns off thirst before rehydration is complete
Lacks CHOs and electrolytes
Depends
Sports drinks are pretty much all the same? T or F
Too high CHOs slows fluid absorption
Sodium content is important
Consumption of sports drinks during exercise = Weight Gain
Those who should use sports drinks, exercise harder and longer and are more likely to burn the glucose during workouts or competitions
Sports drinks are very high in sugar and kcals? T or F
sports drinks have ½ the kcals and sugar of fruit juice and most soft drinks
Sports drinks trigger high insulin response? T or F
Consumed during exercise… ‘slows’ insulin response
A slight rise in insulin boosts energy & performance
Timing of intake is important… sip sports drinks slowly… don’t guzzle a bottle right before exercise!
Sports drinks are for events lasting 60 min +? T or F
Proven to boost performance in events under 60 min, too
For ‘endurance exercise’… bike, run, swim, etc
For ‘stop & go’ exercise’… hockey, basketball, soccer, etc
Sports drinks contain too much salt (sodium)? T or F
Sports drinks contain ‘enough’ sodium to assist with rehydration… but are still classified as ‘low sodium’ by the FDA
Symptoms of caffeine
spikes in blood pressure Disrupted sleep headaches Irritability nervousness / “jittery”
Health Canada and non-governmental reviews recommends how much caffeine?
2.5 mg/kg/day
or the following approximate limits:
4–6 years: 45 mg/day
7–9 years: 62.5 mg/day
10–12 years: 85 mg/day
How much caffeine is considered toxic?
10mg/kg of body weight
150mg/kg = lethal
Pros of caffeine
Alertness Improved memory Improved thinking skills Increased energy Metabolism up 16%
Cons of caffeine
Increase calcium loss Increases blood pressure Increases heart rate Irritates digestive system Cause shakiness
Large doses of energy drinks may cause ?
Light-headedness
Diuretic effect (excess urination)
Laxative effect
Caffeine up to _ mg/kg BW can enhance exercise performance
6
Energy drinks may contain herbal forms of caffeine such as:
Guarana seeds
Kola nuts
Yerbamaté leaves
Impossible to know the exact amounts of caffeine added to the drinks in this manner
