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
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
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
medical conditions such as diabetes
use of systemic/ topical medications
- 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
When does AMD damage first occur?
preventative measures at 40 but too late
Pathogenesis of AMD
exact path. uknown
high oxygen= high oxidativee damage
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 AREDS 2
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
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