AMD & Supplements Of The Eye

PART 1: What is AMD

Age-related macular degeneration (AMD) is the leading cause of blindness. A cross-sectional study in Singapore was performed in 10,0033 people age 40 and above. The study noted that the prevalence of early AMD at 5.1% of the population. The study noted that AMD was more prevalent in the Chinese and the Indians as compared to the Malay population. 1

AMD is a disease that blurs the sharp, central vision you need for “straight-ahead” activities such as reading, sewing, and driving [Image 1]. AMD affects the macula, the part of the eye that allows you to see fine detail [Image 2]. AMD causes no pain but can lead to poor quality of life. 2

amd-little-girl-1200x630

amd_macular_generation_diagram

[Image 1] Blurred vision with AMD 3 [Image 2] Healthy eye vs Eye with AMD 4

Researchers have found that the risk of AMD can be lowered by adopting the following healthy lifestyle choices: 2

  • Avoid smoking

  • Exercise regularly

  • Maintain normal blood pressure and cholesterol levels

  • Adopt a healthy diet rich in antioxidants

PART 2: How To Choose Supplements for the Eye

A landmark trial called the Age-Related Macular Degeneration (AREDS) study was published in 2001. The study recruited 4,757 participants and attempted to identify a supplement formulation that may be able to reduce the risk of progression of AMD. A follow-up study was published in 2013, called AREDS2 with 4,203 participants recruited. The purpose was to identify an improved formulation. The two studies showed a 19-25% reduction of risk in developing advanced AMD. To date, AREDS and AREDS2 is the most evidence-based study that guides us on how to choose an eye supplement. 5

Below are a few supplements to consider to slow the progression of AMD

Lutein & Zeaxanthin 5, 6

  • Lutein and zeaxanthin are antioxidants found in the eye.

  • The human body does not produce lutein and zeaxanthin naturally.

  • They are found naturally in green leafy vegetables

  • The AREDS2 study recommends a daily supplement of lutein 10mg and zeaxanthin 2mg.

Vitamin C & E 5, 6

  • Vitamin C is found in fruit and vegetables, whereas Vitamin E is found in nuts, cereals and sweet potatoes.

  • Vitamin C and E are antioxidants which prevent free radicals from damaging retina cells

  • The AREDS and AREDS 2 recommends a daily dose of vitamin C 500mg and vitamin E 400 IU

Zinc & Copper 5, 6

  • Zinc is a trace molecule that brings Vitamin A from the liver to the retina to produce melanin which protects the eye

  • Poor light vision is linked with zinc deficiency

  • A high intake of zinc may interfere with the absorption of existing copper in the body. Therefore it is recommended to “balance” the intake of zinc with a combination of copper supplementation.

  • The AREDS2 recommends a daily dose of zinc oxide 80mg and cupric oxide 2mg

The AREDS and AREDS2 study concluded the recommended formulation for AMD should contain: 5

  • 500 milligrams (mg) of vitamin C

  • 400 international units of vitamin E

  • 80 mg zinc as zinc oxide

  • 2 mg copper as cupric oxide

  • 10 mg lutein and 2 mg zeaxanthin

 

Other notable eye supplements

Beta Carotene 5, 6

  • Beta-carotene can be found in carrots, tomatoes, chicken liver

  • Provides a high source of vitamin A

  • The AREDS 2 study found that It may increase the risk of lung cancer in people who smoke

  • It was found to affect the absorption of other nutrients

  • Beta-carotene 15mg daily was assessed in the original AREDS  study but was eliminated from the AREDS2 study

Omega 3 (DHA) 5, 6

  • Docosahexaenoic acid (DHA) is found in the retina, suggesting an important function for the eye

  • A lack of DHA and eicosapentaenoic acid (EPA) intake may result in visual impairment, dry eye syndrome and degradation of the retina.

  • However, adding DHA and EPA was not shown to have further benefit in the AREDS2 study.

  • Omega 3 is commonly available as 1000mg of fish oil (providing 180mg of EPA and 120mg of EPA). The recommended daily dose is 1 capsule 3 times daily.

Marigold formulations 5, 7

  • Marigold flowers (Tagetes erecta L.) contain high amounts of lutein and a minor amount of zeaxanthin

  • Both lutein and zeaxanthin contributes to eye health [Refer above]

Bilberry formulations  8

  • Bilberry (Vaccinium myrtillus) is a small dark blue berry.

  • Bilberry extract  contains high levels of anthocyanins

  • Anthocyanins are a type of flavonoid which has antioxidant effects

  • Bilberry supplementation is associated with improvements in symptoms of tired eyes, eye pain, heavy eyes, foreign body sensation

  • This formulation is suitable for people who spend long hours on the screen

Evening Primrose Oil (EPO) 9

  • EPO is extracted from the seeds of the evening primrose plant (O biennis)

  • It contains linoleic acid which is a type of essential fatty acid (EFA). It is a high source of Omega 6.

  • EPO is normally used for stimulating skin and hair growth as well as maintaining reproductive capability

  • It is potentially useful for people who suffer from dry eyes

  • EPO is widely available in local pharmacies in capsule form of 1000mg (to take 1-2 capsules daily)

 

References:

  1. Prevalence, racial variations and risk factors of age-related macular degeneration in Singaporean Chinese, Indians and Malays. CMG Cheung, X Li, TY Wong, et al. (2014) American Academy of Ophthalmology

  2. Facts about age-related macular degeneration. National Eye Institute. (web accessed May 2019) Web link: https://nei.nih.gov/health/maculardegen/armd_facts

  3. What is age-related macular degeneration? M Haddril & C Slonim. (Web accessed May 2019) Web link: https://www.allaboutvision.com/conditions/amd.htm

  4. Macular Degeneration. Centre for Sight. (Web accessed May 2019) Web link: https://www.centreforsight.com/eye-conditions/macular-degeneration

  5. Age-related macular degeneration Preferred Practice Guideline. AAO Retina & Vitreous PPP Panel, Hoskins Center for Quality Eye Care. (Jan 2015) American Academy of Ophthalmology.

  6. Diet and Nutrition. American Optometric Association. (Web accessed May 2019) Web link: https://www.aoa.org/patients-and-public/caring-for-your-vision/diet-and-nutrition

  7. Lutein content in Marigold Flower (Tagetes erecta L.) concentrates used for production of food supplements. M Sivel, S Kracmar, V Kuban et al. (2014) Czech Journal of Food Science.

  8. Bilberry extract supplementation for preventing eye fatigue in video display terminal workers. Y Ozawa, M Kawashima, K Tsubota, et al. (2015) The Journal of Nutrition, Health & Aging.

  9. A review of the clinical efficacy of evening primrose. D Stonemetz. (2008) Holistic Nursing Practice.