Nutrition Flashcards
1
Q
Ca2+ in pregnancy
A
- Ca2+ absorption doubles
- ~30g Ca diverted to fetal skeleton
- Inc estrogen -> inc osteoblast activity
- RDA
A. 14-18 yrs: 1300 mg
B. 19-50 yrs: 1000mg
2
Q
Ca2+ in lactation
A
- Ca2+ absorption returns to pre-pregnancy level
- Supplementation has little/no effect on bone loss
- Mineral content inc after weaning
3
Q
Vitamin D
A
- Essential for intestinal Ca2+ absorption
- RDA
A. 0-12mo: 400 IU
B. 1-70 yrs: 600 IU
C. 71+ yrs: 800 IU - Maintains adequate serum Ca and P levels
A. Enable normal bone mineralization
B. Prevent hypocalcemia tetany - Acceptable levels debated
- Groups at risk for deficiency
A. Breastfed infants
B. Older adults
C. Limited sun exposure
D. People w/ dark skin
E. IBD and other conditions causing fat malabsorption
F. Obese or bypass
4
Q
Vitamin A
A
- Deficiency: bone abnormalities in animal models
- Xs can be toxic (supplements): hypercalcemia and bone resorption
- Long-term intake >1500 mcg/day -> (-) impact on bone
- Intake assessments unreliable
5
Q
Magnesium
A
- Inc osteoblast/clast activity
- Supplementation not shown beneficial
- Mg and Ca supplements shouldn’t be taken together (dec Ca absorption)
6
Q
Vitamin K
A
1. Vitamin K1
A. Phylloquinone
B. Green leafy veggies
C. Main dietary form
2. Vitamin K2
A. Series menaquinones
B. Bacterial origin
C. Various animal-based foods and fermented foods
3. Bone metabolism
A. Carboxylation of osteoclastogenesis
B. Inhibits osteoclastogenesis
C. Unclear if supplements dec risk of osteoporosis
1. Several studies show dec fracture risk
7
Q
Vitamin C
A
- Cofactor for hydroxylation of lys and pro during collagen synthesis
- Observational studies inconsistent
- Lack of good studies
- Recommendations
A. LPI = 400 mg/day
B. RDA- 90 mg/day = nonsmoking men
- 75 mg/day = nonsmoking women
8
Q
Fluoride
A
- May stimulate bone formation via direct effects of osteoblasts
- Studies inconclusive
- Supplementation not approved by FDA
9
Q
Energy availability equation
A
EA = (EI - EEE)/FFM
- EI = energy intake
- EEE = energy expenditure in exercise
- FFM = fat free mass (Kg)
10
Q
Carbohydrate intake recommendation
A
- Very light training = 3-5 g/kg
- Moderate training 60 min = 5-7 g/kg
- Moderate training 1-3 hr = 6-10 g/kg
- High training 5 hr = 8-12 g/kg
11
Q
Carb recommendation during high-intensity exercise
A
Small amts, mouth rinse
1. Sports drinks
12
Q
Carb recommendation during endurance exercise (1-2.5 Hr)
A
30-60 g/hr
- Sports products
- Timing meets goals
13
Q
Carb recommendation during ultra endurance exercise (>2.5-3 hr)
A
Up to 90 g/hr
- Higher intake -> better performance
- Multiple transportable CHO -> high rates CHO oxidation during exercise
14
Q
General fueling up
A
Prep for <90 min exercise
15
Q
Carb loading
A
Prep for >90 min exercise
