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Eyes on Eye Care  

Lutein and Zeaxanthin: vision benefits

Good nutrition is essential to maintain the health and function of the eyes. Two important nutrients which can help achieve this are Lutein and Zeaxanthin. They help reduce the risk of Macular degeneration and Cataracts.

Humans derive zeaxanthin and lutein from a plant diet. They are both xanthophyll carotenoids contained within the retina of the eye. Zeaxanthin predominates within the central macula, whereas lutein predominates within the peripheral retina. They are found in high quantities in green leafy vegetables such as spinach and kale.

In nature, lutein and zeaxanthin modulate excess light energy to prevent damage to plants from too much sunlight, especially from high-energy light rays called blue light. As in plants, Lutein and zeaxanthin appear to have important antioxidant functions in the eyes and the rest of the body. They help keep the eyes safe from oxidative stress and the high-energy photons of blue light. Along with other natural antioxidants, these important pigments guard the body from damaging effects of free radicals, which are unstable molecules that can destroy cells and play a role in many diseases.

The AREDS2 Study revealed a 10 to 25 percent reduced risk of AMD progression in participants with early signs of macular degeneration. These participants took a nutritional supplement that contained 10 mg lutein and 2 mg zeaxanthin (and no beta-carotene) every day for the 5-year study period.  It is unknown at this time whether supplements have the same effect as lutein and zeaxanthin obtained through food sources. The following table shows the foods with the highest concentration of Lutein and Zeaxanthin.

 

FOODS CONTAINING LUTEIN AND ZEAXANTHIN

Food Serving mg
Kale (cooked) 1 cup 23.7
Spinach (cooked) 1 cup 20.4
Collards (cooked) 1 cup 14.6
Turnip greens (cooked) 1 cup 12.2
Spinach (raw) 1 cup 3.7
Green peas (canned) 1 cup 2.2
Corn (canned) 1 cup 2.2
Broccoli (cooked) 1 cup 1.7
Romaine lettuce (raw) 1 cup 1.3
Carrots (cooked) 1 cup 1.1
Green beans (cooked) 1 cup 0.8
Eggs 2 (large) 0.3

Source:  USDA National Nutrient Database for Standard Reference, Release 22 (2009)

This article is written by or on behalf of an outsourced columnist and does not necessarily reflect the views of Castanet.





Alzheimer's and eyecare

Alzheimer’s is a progressive neurological condition. It is the most common form of dementia, leading to memory loss, difficulty making decisions and performing daily activities. Common risk factors for Alzheimer’s are aging and genetics. In Alzheimer’s there is a loss and shrinkage of neurons (nerve cells). The hallmarks in Alzheimer’s are the presence of plaques and tangles. The plaques contain a central core of protein known as amyloid. The amyloid protein consists of a protein chain called beta-amyloid. It is believed that beta-amyloid accumulates due to abnormal processing of the amyloid precursor protein molecule. Although there is no cure for Alzheimer’s, current treatments are available to slow the progression of symptoms.

Currently, doctors are using PET (Positron Emission Tomography) and MRI (Magnetic Resonance Imaging) of the brain to detect Alzheimer’s. In the near future, Alzheimer’s disease may be able to be detected during a routine eye exam. The eyes are a sensory organ with direct connection to the brain, via the optic nerve. This will allow Alzheimer’s to be detected much earlier and at a cheaper cost. The early detection can create a group of candidates that can serve in prevention trials.

A study conducted by Australia's Commonwealth Scientific and Industrial Research Organization found the presence of beta-amyloid in the retina. In a study of 200 participants, 40 patients exhibited retinal changes that strongly correlated with amyloid plaque development in the brain. The study will be completed later this year.

A second study SAPPHIRE II, conducted by Cognoptix Inc, found the presence of beta-amyloid in the lens of the eye. This had a strong correlation to PET amyloid brain imaging. Cognoptix is planning on creating a method for primary care clinicians to detect of these amyloid plaques. The method consists of a laser eye scanning device in combination with ophthalmic ointment.

Eye exams are proving to be more important as research progresses. What will they find next?

This article is written by or on behalf of an outsourced columnist and does not necessarily reflect the views of Castanet.



Computer Vision Syndrome

The evolution of technology has brought us to an era of many portable electronic devices. Many of our daily tasks have moved from print on paper to the internet. This has made it almost impossible to avoid these portable electronic devices. Even though technology has made our life easier, computers and smartphones can lead to Computer Vision Syndrome.

 

Risk factors for Computer Vision Syndrome include:

  • How close you sit to your computer or device
  • The length of time spent in front of the computer. Certain activities take longer than others.
  • Reduced Blinking
  • Dry Eyes
  • Uncorrected Vision Problems

 

Common signs and symptoms of computer vision syndrome include:

  • Dry Eyes, which can lead to red, irritated eyes
  • Intermittent blurred vision when viewing your screen or device
  • Blurred distance vision when looking away from your screen or device
  • Headaches
  • Neck and/or back pain

 

How to reduce the risk of Computer Vision Syndrome:

1.  Get a comprehensive eye exam

Your Optometrist can find out if you require glasses for the computer. He/she can also recommend an anti-glare tint to reduce reflections from the computer devices.

2.  Use proper lighting

Your ambient lighting should be about as bright as that typically found in most offices. Light entering through windows should be eliminated with the use of curtains. Alternatively, make sure the outdoor lighting is not directly in front of or behind your computer device.

3.  Minimize Glare by placing an anti-glare screen on your monitor.

4.  Upgrade your display to an LCD. Older CRT displays cause a ‘flicker’

5.  Adjust your computer display settings:

  • Brightness should be the same as the brightness of your surroundings
  • Black font on a white background is the most comfortable
  • Reducing the color temperature so that less blue light is emitted will also help.

6.  Blink more often

  • When we concentrate on computer screens, we blink significantly less, causing our eyes to become very dry.

7.  Exercise your eyes

  • Remember the 20-20-20 rule. Take a break every 20 minutes, look at an object at least 20 feet away, and stare at the object for at least 20 seconds

8.  Modify your workstation

  • Position your screen approximately 20 inches from your eyes, approximately 10 to 15 degrees below your eyes
  • Adjust your workstation and chair to the correct height

This article is written by or on behalf of an outsourced columnist and does not necessarily reflect the views of Castanet.





Exotic health for your eyes

We have all been told that eating carrots is good for our eyes. However, recent research shows that eating some exotic fruits can benefit our ocular health.

Dragon Fruit, Jack Fruit, Buddha’s Hand, Rambutan and Custard Apple are rich in vitamin C. Both Custard Apples and Mangosteens contain the B Complex Vitamins, while Kiwanos contain Beta carotene.  These fruits can protect the eyes in many different ways:

Dragon Fruit: Dragon Fruit is a member of the cactus family and helps nourish and protect the cornea.  Dragon Fruit can also help clear red eyes and is considered cooling.

Jack Fruit: Jack Fruit also contains vitamin A and antioxidants in addition to Vitamin C, and may reduce the risk of cataracts and vision loss from macular degeneration.

Buddha’s Hand: Buddha’s Hand belongs to the citrus family and can help protect the delicate capillaries of the retina.

Rambutan: Besides being rich in vitamin C, Rambutan also contains bioflavonoids, which are plant pigments with antioxidant and anti-inflammatory properties. These two nutrients complement each other and may help reduce the risk of age-related vision problems by protecting the eyes from damage caused by free radicals.

Custard Apples: In addition to vitamins C and B, Custard Apples also contain potassium. Research shows potassium-rich foods help reduce excess fluid under the skin that causes puffy eyes.

Mangosteen: Appear to reduce the risk of macular degeneration among women, according to a recent study.

Kiwano: The green pulp of a Kiwano helps protect the surface of the eye and is essential for good night vision.

 

So the next time you’re at the grocery store, try and add some exotic fruits as a part of your diet.

This article is written by or on behalf of an outsourced columnist and does not necessarily reflect the views of Castanet.



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About the Author

Dr. Sunil Parekh is originally from Kamloops, B.C. He attended Optometry School in London, England. During his time there he gained experience from Moorfields Eye Hospital and Queen Alexandria Hospital. After graduating, Dr. Parekh worked in the UK for a year and took part in a friend's charity called 'Eye for India'. Sunil travelled with a group of friends to Calcutta, India for their first mission and provided eye exams and glasses. Dr. Parekh always wanted to move back to B.C, and decided to make the beautiful Okanagan his home with his wife.



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The views expressed are strictly those of the author and not necessarily those of Castanet. Castanet does not warrant the contents.

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