there is high variability in what factors affecting nutrient requirements in the elderly?
- body composition
- abilities to absorb and metabolize nutrients
- drug intake
What are the elderly age categories for RDA?
T or F
Most studies on nutrient requirements have been carried out on young healthy adults
What happens to energy requirements for the elderly?
decreased energy requirements due decreased muscle mass leading to lower BMR
What happens to protein requirements of the elderly?
no significant effect of age on requirement
What happens to total body glucose oxidation rate with aging?
- a modest decrease
- those over 70 have ~ 10 % less glucose oxidation rate than 19-29 year olds
After what age does brain mass slowly decrease?
T or F
the carbohydrate EAR changes with age
- the cho EAR is the same for all adults
How much less brain mass does a 76- 80 year old man have?
How will this affect glucose oxidation?
- average brain mass 76-80 is 8 to 9% less
- there is an insignificant decrease in brain glucose oxidation rate
What are elderly fiber requirements, AI, based on?
- studies on dietary fiber and coronary heart disease
- highest intake level for each age group is used to set AI
How is the AI for linoleic acid and alpha-linolenic set?
highest median intake have been used for linoleic acid and alpha-linolenic
What are some functions of linoleic acid?
- essential compound of structural membrane lipids
- involved with cell signaling
- precursor of eicosanoids
- required for normal skin function
What are some functions of alpha-linolenic acid?
- involved with neurological development and growth
- precursor of eicosanoids
How is the AI for older adults obtained?
extrapolated from younger adults based on the combined average requirements for men ad women of median energy intakes (which do decrease with age)
How is the AI for water in older adults set?
- hydration status is normal over a wide range of intakes
- total water for elderly based on: median intakes of young adults; to ensure water intake is not limited (decline in ability to consume adequate water in response to thirst)
Do water soluble vitamin requirements increase with age?
- there is little evidence of increased requirement in elderly
- no data for: thiamin, riboflavin, pantothenic acid, biotin, choline, niacin, vitamin C, E, A, K, selenium, Cu, Iodine, Mn, Mo, Zn, phosphorus
T or F
Most elderly obtain sufficient B12 from food
what precent of mature adults loes their ability to adequately absorb protein-bound vit. B12 in foods?
~10 - 30%
What precent of people >50 years have atrophic gastritis with low stomach acid secretion.
what could atrophic gastritus lead to?
- 10 - 30%
- may have decreased bioavailability of B12 from food
Is there a bioavailability correction factor for persons with atrophic gastritus?
- there is insufficient info for bioavailability correction factor for people with atrophic gastritis who obtain their B12 from animal foods
Is the bioavailability of crystalline B12 altered in people with atrophic gastritis or age?
- same EAR and RDA if dietary sources were fortified foods, supplements or both
What is the EAR and RDA for B12 for adults >51 years?
- same as for younger adults
- recommendation that B12 fortified foods and supplements be used to meet much of the requirements
What recommendations hav been made for those over 60 in regards to B12?
should consider taking as a supplement or fortified cereal product where it is sprayed on, not bound up with the food
How is the AI for Vitamin D affected by aging?
- the AI remains the same for those 51 - 70
- it increases >70
Why does the Vitamin D recommendation increase with age?
- absorption efficiency decreases in older persons
- decreased no. of vit D receptors
- requirement is greater for elderly = 20 µg/d
What is the vit D recommendation based on?
the amount of blood to maintain blood levels of 25-(OH)D associated with optimal bone health
What is the RDA of vitamin D equivalent to in milk?
- 2 quarts (1.9L) of milk to get 20 µg/d
- very difficult in older persons- supplements
The RDA (1000 mg/d) in ages 19-50 years based on clinical trial data showing what?
- an increase in BMD (bone mass density)
- individuals > 50 years show a decrease in Ca absorption
- most older adults consume Ca well below recommended levels
what precent of adults over 60 consume the recommended 100% Ca recommendation?
- ~13% of males
- 4% of females
Why are older adults 50-70 Ca intake requirements raised?
- decreased Ca intake increased risk for osteoporosis and other diseases HTN, colon cancer
- increasing older adults Ca intake leads to decreased bone loss and risk of fractures
How are Mg requirements set? how do they vary with age?
- balance studies
- Mg requirements are greater for those over 30 years
Why do magnesium requirements increase for those over 30?
- renal function is critical in maintaining Mg status
- renal function decreases with age
How do iron requirements change in postmenopausal women?
- as for me basal Fe losses = only component of Fe needs
- EAR and RDA are decreased for postmenopausal women