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Flashcards in Nutrition and the Eye Deck (29):

Current therapy for glaucoma focused on?

Lowering the intraocular pressure/ medications that do this


Other considerations of therapy for glaucoma?

o Circulatory issues, idependent role or cofactor
o Neuro protection issues
o Adjunct therapies


How does alcohol effect glaucoma?

- alcohol decreases IOP
o effect not significant enough for theurapuetic measures
o large comsumption of beer is similar to water provocative tests


How does caffine affect glaucoma?

o Over 2-3 mmhg increase within 2-3 hours
o Has antioxidants ( drinking it in moderation can be beneficial)
o Increases metabolic rate
o Secondary benefits to blood flow


Marijuana effect on glaucoma? Active ingredient?

o Lowers IOP 3-4 mmhg
o Only effective for short period of time; would have to consume it every 3 hours
o Taking more has no benefit / increased dosage does not lead to greater efficiency
o Active ingredient is delta-9-tetrahydrocannabinoid
o Cannabinoid


Fat intake effect on glaucoma?

o Very little research
o Dietary fat may modulate the availability of intraocular prostagandins
o Total fat intake not associated with glaucoma
o high ratio of n-3 to n-6 polyunsaturated fat appears to increase the risk of POAG, particularly high-tension POAG. *
o high ratio not good
o in summary, can’t advice pts to take more or less of types of fat


How does ginko biloba affect glaucoma?

o Reduction of platelet aggregation
o increasing vasodilation
o Reducing blood viscosity
o quenching of free radicals
o In humans it increased end diastolic flow velocity in the ophthalmic artery of healthy volunteers


Ginko B. affect visual fields?

• One study showed improvement VFS in patients with normal tension glaucoma who receieved 120 mg of ginko a day (4 weeks)


What increases in vfs due to ginko?

• Increased blood flow in all points
• Increased blood volume in superior nasal and sup temporal areas
• Increased blood velocity in inf-temporal and sup-temporal areas
• Blood flow parameters are measured using the Heidelberg retina flowmeter


Human Lens

o Grows throughout life
o Better organelles than rest of body
o Lower oxygen- prevent oxidative damage
o Relatively dehydrated structure
o Aqueous humor has 14x amount of vitamin C than blood
o Yet if one lives long enough, they will develop cataract


Carotenoids effect on cataracts

o High dietary intake of lutien and zeaxanthin yielded 22% reduction in risk for cataract surgery


Vitamin C effect on cataracts?

o Vitamin C: supplements 10 years or greater were 45% less likely to require cataract surgery


Multivitamins and Cataract

Blue Mountains Eye Study found that long-term use of daily multivitamins protected against the development of nuclear and cortical cataracts


Beaver Dam Eye Study

Study found no relationship between the incidence of nuclear sclerotic cataract and increased dietary intake of vitamin C, vitamin E, alpha-carotene or beta-carotene; unless other risk factors were present



high intake of vitamin C, E, and beta carotene had no effect on incidence of either cataract development or extraction during an approximate six-year period



Centrum multivitamins are associated with decreased risk of nuclear cataract


Cataract Formation Factors

environmental (radiation)
medical conditions such as diabetes
use of systemic/ topical medications


AMD statistics

- major cause of blindness; more than 50%
- 1.2 million U.S. residents are living with neovascular AMD and 970,000 have geographic atrophy (Numbers expected to rise by 50% in 2024)


Major risk factors of AMD

Family history


When does AMD damage first occur?

preventative measures at 40 but too late


Pathogenesis of AMD

exact path. uknown
high oxygen= high oxidativee damage
blue light


Natural Protection against AMD

antioxidants present in eye (vitamin C, aeaxanthin, meso-zeaxanthin, leutin)
pupils get smaller
yellowing of lens cuts out blue ligt


Omega 3 and AMD

o Prior studies, diet high in omega 3 fat, greater chance of AMD
o AREDS 23
• —a reduced likelihood of progression to central geographic atrophy in individuals with bilateral drusen at baseline


Vitamin C effect on AMD

no effect


Carotenoids effect on AMD

some show benefit; some don't ; o capable of quenching the reactive oxidative species, thus protecting the retinal pigment epithelium from oxidative damage
o Macular carotenoids absorbs blue light


2 carotenoids found in retina?

leutin and Zeaxanthin(greater amount


Relationship between carotene and smokers?

- high dosage of beta carotene or in combination with vitamin E are associated with sig. risk of developing lung cancer


AREDS 2 and carotene

But added lutein 10 mg and zeaxanthin 2 mg found
—18% reduction of preogession to advanced AMD


Zinc and AMD

- zinc may help AMD
- high dosage 80 mg/ day increases chance of hospitalizations for genitourinary causes
- high in aqueous humore can cause cataracts
- Participants with moderate AMD in the antioxidant combination plus zinc group were 25% less likely to experience AMD progression than participants in the placebo group
o Beta carotene
o Vitamin-C
o Vitamin-E
o Zinc