Vitamins (slide 0-36) Flashcards
do the micronutrients yield energy?
nope, essential in diet in small quantities and perform specific biological functions
categories - nutrient status assessment
A: anthropometrics
B: biochemical
C: clinical
D: dietary
Nutrient status ax - A
waist circumference - weight
Nutrient status ax - B
Blood tests (micronutrient measurement)
Nutrient status ax - C
Physical exam
Nutrient status ax - D
24-hour recall
A,B,C or D - which one usually detects nutrients discrepancies before the others?
B before A and C
Direct assessment method
Biopsy, blood test
Indirect assessment
Dietary
Vitamins typically classified according to (2)
1) solubility
2) physiological function
Fat soluble vitamins
A, D, E, K
Water-soluble vitamins
Vitamin C, B-complex vitamins
Fat soluble - absorption and transport
With fat in lymph (slower)
Carrier needed for transport
Water soluble - absorption and transport
With water into blood (rapid)
Free to move
Fat soluble - storage and deficiencies/toxicity
Stored in fat, liver, cell membranes
↑ risk toxicity
Water soluble - storage and deficiencies/toxicities
Not stored, excess excreted in urine (so daily needs)
↑ risk deficiency
Most people, including athletes, can get all the nutrients they need from diet alone : (3 components of a good diet)
- Balanced
- Varied
- Nutrient-dense foods
Define enrichment
Adding back of nutrients that were lost during processing
Define fortification
Addition of nutrients that are not found in original food
Example of flour enrichment (5)
Thiamine (B1)
Riboflavin (B2)
Niacin (B3)
Folic acid (B9)
Iron
Example of milk fortification (2)
Vitamin D
Vitamin A (skim or 1%)
Define supplements
Concentrated sources of vitamins found naturally in foods
Advantage of supplements
Used to prevent and treat nutrient deficiencies
Disadvantage of supplements
Underlying problem —- poor diet
Define megadose supplements
Contains several times the DRI
No evidence helpful
May risk intake over the UL
The DRI have been established for each vitamin, for who?
Healthy people who are moderately active
4 effects of exercise on vitamins
↓ absorption
↑ losses
↑ utilization
↑ needs
Athletes have increased vitamins needs (T or F)
We actually don’t know - so FALSE because the DRI is made for moderately active (which is maybe not representative of the needs of an athlete)
Factors for low vitamin intake in athletes (3)
- Low fruit and vegetable intake
- Low fat diets
- Caloric restriction
Deficiencies progress over time - Mild
Poor intake and/or absorption
Deficiencies progress over time - Subclinical (moderate)
Vitamin-specific function impaired
No medical sign of disease
Deficiencies progress over time - Clinical (severe)
Medical signs and symptoms of disease
Initial symptoms vague of excessive amounts of vitamins
Lethargy, malaise
Continued exposure to high dose can lead to
Disease
Etiology of toxicities:
+++ use of self-prescribed vitamin supplements
Prevention of toxicities
Avoid consumption above UL
Treatment of toxicities
Discontinue supplement use
Classification by physiological function - Energy metabolism (6)
- Thiamin (B1)
- Riboflavin (B2)
- Niacin (B3)
- Pantothenic acid (B5)
- B6
- Biotin
Classification by physiological function - Antioxidants (3)
Vitamin A
Vitamin C
Vitamin E
Classification by physiological function - circulatory system (4)
Folate
B12
Vitamin K
B6
Classification by physiological function - Growth and development
Vitamin A
Vitamin D
Main function of thiamin
Release of energy from carbs, proteins and fats
Where is thiamin prevelant?
Skeletal muscle
Excellent sources of thiamin
Whole grain products
- breads
- cereals
- pastas
Enriched flours
Good sources of thiamin
Beans and peas
Pork
Trout
Seafood
Thiamin deficiency - name
Berri-Berri Disease
S&S of Berri-Berri disease
Pain/tingling in calf muscles
Fatigue
Headaches
Decrease appetite
Muscle weakness
Mental confusion
Thiamin toxicity
NONE
Main function of riboflavin (B2)
Promotes carb & fat oxidation
Riboflavin is part of 2 compounds
Flavin mononucleotide (FMN)
Flavin adenin dinucleotide (FAD)
Excellent sources of B2 (riboflavin)
Dairy products
- milk
- cream
- butter
- cheese
- yogourt
Good sources of riboflavin
Breads and cereals
Green leafy vegetables
Meat
Eggs
Liver
Characteristic of riboflavin deficiency
Oral lesions
Toxicity of riboflavin
NONE
Main functions of niacin (4)
- Anaerobic glycolysis
- Carbohydrate & fat oxidation
- Fatty acid synthesis
- Oxidation of glutamate (AA)
Niacin is part of 2 compounds
Nicotinamide adenine dinucleotide (NAD)
NADP
Excellent sources of niacin
Protein foods
- beef
- poultry
- fish
- pork
Enriched flours
Good source of niacin
Lentils
Nuts
Niacin deficiency - name and symptoms
Pellagra
- diarrhea
- dermatitis
- dementia
- death
Toxicity of niacin
Niacin flush
Red/warm, itchy, burning skin
Headache
Nausea
Name of B6
Pyridoxine
Main functions of pyridoxine (4)
Amino acid metabolism
Release of glucose from glycogen
Formation of hemoglobin & RBC
Degradation of homcysteine
Pyridoxine is part of a co-enzyme that catalyzes several reaction - name it
PLP (pyrixidoxal phosphate)
Excellent sources of B6
Meat
Nuts
Legumes
Green leafy vegetables
Other sources of B6
Bananas
Potatoes
Avocado
Name of B5
Pantothenic acid
Main function of B5
Vital for aerobic ATP production
Main function of B7
Involved in several energy-related reactions
Food sources of B5 and B7
Nearly all goods
Deficiencies in B5
Extremely rare
Deficiencies in B7
Extremely rare
Trained athletes have increase needs for 3 vitamins - name them
Thiamine, riboflavin, B6
Deficiencies in B-vitamins in athletes is usually due to
caloric restriction
Main function of antioxidants
Protect cells and tissues from damage
