Keeping age-related macular degeneration (AMD) and cataract at bay.
VISION is one of the most amazing gifts we have been given. Think what you can’t do without it. Actually, surveys show that people fear losing their sight more than any other sense, yet we tend to take it for granted.
As we grow older, our vision is not as sharp; prolonged exposure to ultraviolet (UV) rays and harmful blue light may cause excessive free radical damage to our eyes, which may lead to aged-related macular degeneration (AMD) and cataract.
Age-related macular degeneration (AMD)
Think of your retina as the film in your camera (non-digital). In the retina, rods and cones (photoreceptor cells) convert the image into electrical impulses, which travel to the brain via the optic nerve.
That is how the eye, or rather the brain, sees images.
The most sensitive part of the retina is the macular. There, millions of cones are tightly packed to create a high-resolution image that produces the sharp central vision needed for activities like reading, writing, driving, and even recognising faces. It is the macular that can deteriorate with age.
Because the macular alone is affected, central vision is lost (though total blindness is avoided).
Macular degeneration causes no pain. It affects one-third of adults over the age of 75, and is the principal cause of visual disability in people over 65 years of age. Age is by far the greatest risk factor.
Cataract defined
The lens, which focuses light rays into the retina, is supposed to be transparent. When the lenses become opaque, the opaque areas are called cataracts. Cataracts are the leading cause of impaired vision and blindness worldwide, affecting up to 40% of people over 75.
They are most often caused by overexposure to intense light (sunlight), but other factors can contribute to their formation. These include cigarette smoking, hereditary factors, injury, diabetes, and certain medications. Cataracts usually develop slowly, starting with blurred vision, seeing spots, and the impression that a film is covering the eyes.
Lutein and Zeaxanthin distribution in eye
Carotenoids are the red, yellow, and orange pigments found in yellow-orange fruits and vegetables, dark green, leafy vegetables, and corn.
Of the more than 600 plant pigments found in nature called carotenoids, only two carotenoids – Zeaxanthin and Lutein – selectively accumulates in the retina, macular, and lens of the eye.
Zeaxanthin is the dominant component in the centre of the macular, while Lutein dominates at the outer edges.
The eye is selective and preferentially places dietary Zeaxanthin in the very centre of the macular, the most critical area for central vision with the greatest need for protection.
Concentrated in the lenses and retina, these two carotenoids fulfill two essential functions:
- Shields the eyes from damaging ultraviolet (UV) light
- Acting as a filter to shield against harmful blue light, and as antioxidants, both Lutein and Zeaxanthin help to reduce the risk of age-related macular degeneration (AMD) and cataract.
- Acts as antioxidants to protect the lenses, retina, and macula against free radical damage due to exposure to the sun, computer screens, and other forms of light.
- Both Lutein and Zeaxanthin absorb the very high-energy and most damaging portions of the light spectrum (ultraviolet blue).
The absorption of the high-energy light spectrum is critical for the protection of the lens, retina, and macula portions of the eye. High-energy blue light also generates “free radicals” that cause damage to the tissues of the eye.
Like many other important nutrients, Lutein and Zeaxanthin are not manufactured in the body. The only way to consume it is by consuming food rich in these antioxidants or by supplementing with Lutein and Zeaxanthin.
In the body, Lutein and Zeaxanthin is found primarily in the skin, the eyes, the cervix, brain, liver, lung, prostate, blood serum, and breast. Unfortunately as we age, the concentration of Lutein and Zeaxanthin in the eyes decline.
In addition to its role in preventing cataracts, Lutein and Zeaxanthin may improve vision in people who already have cataracts. A study found that when patients with age-related cataracts supplemented with Lutein and Zeaxanthin, their visual acuity improved.
Two things to ensure when buying a Lutein and Zeaxanthin supplement:
1. Standardised marigold flower (Tagates erecta) containing a minimum 15% Lutein esters and 40% Zeaxanthin is used to ensure every capsule contains the exact amount of active ingredients as stated on the label.
Not all herbal eye products are created equal even if they are using marigold flower extract. Many of these extracts yield different levels of active ingredients depending on many factors such time of the year harvested, plant part used, soil conditions (may be depleted in certain nutrients), species used, and geographical location where herb is grown.
2. Concentrated Lutein and Zeaxanthin is used
Ensure the eye supplement contains at least 6mg but preferably 10mg of standardised Lutein. Many Lutein and Zeaxanthin supplements contain only very small amounts of Zeaxanthin – in the micrograms (mcg) whereas studies have found that Zeaxanthin is beneficial only when their amounts are much higher, e.g. at least 5mg daily.
