Tag Archives: macular degeneration

Antioxidants in Green Leafy Vegetables

Antioxidants you find in the red of tomatoes and the yellow plant pigments in carrots  are called carotenoids. You also find them in green leafy vegetables They belong to the family of phytonutrients. See also my article: Phytonutrients, compounds from the garden.
These carotenoids are powerful antioxidants to fight against heart disease and certain forms of cancer.

Research has shown promising results from a number of carotenoids, particularly lycopene
(also found in tomatoes), lutein (found in vegetables such as spinach and kale), and
zeaxanthin ( found in dark green leafy vegetables). All three play a powerful role as antioxidants  in cancer prevention.

Researchers in the Tufts University Carotenoids Health Laboratory say: “Skipping fruits &
vegetables is part of the classic “profile” of people who develop cancers of the head and
neck, but that increasing your intake of these antioxidants rich products may cut your risk for recurrence of these cancers.

In one study, researchers found that people in northern Italy who ate seven or more
servings  of raw tomatoes every week  had a 60% lower change of developing colon, rectal,
and stomach cancer than those who only ate two servings or less.

German researchers have found that cooked tomato products containing some oil –
such as spaghetti sauce – boost lycopene absorption dramatically. They believe that
heating  and crushing releases more lycopene, and that the body  needs substances in
oil to  help better absorption.

Harvard researchers, looking at green leafy vegetables, especially spinach, had quite
an eye-opener. They found that people eating the most lutein and zeaxanthin – which
are two carotenoids , powerful antioxidants found in these vegetables – had a 43% lower risk of macular degeneration  than those eating the least.
Macular degeneration is the leading cause of irreversible vision loss in people  over 50.
Lutein and zeaxanthin concentrate in your retinas and protect them by absorbing
harmful blue-wavelength light found in sunshine.

Other members of the Phytonutrients are: flavonoids, indoles,  lignans, monoterpenes, saponins, organosulfur – and phenolic compounds, which are all powerful antioxidants,
I will discuss in future articles.  If you like to know more about plant-based nutrition,
I refer to : Nutrition studies.org

Problems Concerning the Eyes

Cataract surgery is most common for people over the age
of sixty In the US, eye surgeons perform 1.3 million cataract
operations every year for a total cost of US $3.5 billion.

The lens of the eye collects and focus light on the retina.
It is important for the lens to stay clear throughout our lifetime,
In order to function properly. As we age, various components
of the lens may get damaged, leading to cataracts.

Medical research has proven that supply of sufficient anti-
oxidants at an early age can prevent cataract formation.
Antioxidants are needed to combat against free radicals,
due to ultraviolet sunlight.

In particular the fluid around the lens of the eye has to be
protected by antioxidants against oxidative damage.
The most important antioxidant is vitamin C, which is found
in high concentration around the lens, as well as vitamin E,
alpha-lipoic acid and beta-carotine.

A study showed that consuming vitamins in supplementation
protects the eye and decrease the risk of developing
cataracts by 50%. There is sufficient evidence that taking
antioxidants is an inexpensive way to decrease cataract
formation.

Another problem concerning the eye is macular degeneration.
It is the leading cause of blindness in people over the age of
sixty.

This is the decay of an important part of the retina called
macula. This is the area, which deals with central vision,
where the greatest concentration of photoreceptors are located.

We recoqnize wet and dry forms. Ninety percent of the cases
represent the dry form, in which central vision gradually
reduces and may proceed to the wet form for the remaining
ten percent.

There is currently no treatment available for the dry form.
The wet form can be treated via laser photocoagulation,
by which new vessel formation can be slowed down, which
causes swelling and bleeding into the retina.
Blindness usually follows rather quickly.

Theories suggest that light entering the eye and focused on
the macula of the retina causes significant free-radical
production in the outer aspect of the photoreceptors.

If there are no sufficient antioxidants available to the
photoreceptors, lipofuscin formation, a toxic substance,
within the retinal pigment epithelium, causes more oxidation
damage to the retina and research believe it is actually
the cause of damage and destruction of these sensitive
photoreceptors.

Lipofuscin accumulate in the pigment epithelium cells and
are eventually excreted in the form of drusen, which is one
of the first indications of macular degeneration development.

The development of drusen separates the photoreceptors
of the eye from its blood supply and causes an area of
blindness.

High-energy ultraviolet light and visible blue light are in
particular responsible for the production of free radicals
in the retina of the eye.

Our natural antioxidant defence system that protects us from
this free radical damage, declines when we get older.
Macular degeneration is characterised by low levels of zinc,
selinium, vitamin C, vitamin E and carotenoid.

High levels of carotenoids, called lutein and zeaxanthine,
absorb the blue light portion of visible light, that can damage
the lens and he retina of the eye. They are strong antioxidants
and are found in corn and leafy green vegetables.

CoQ10 can also play a part in reducing the oxidative damage
caused by free radicals.

Glutathione, which is a very potent antioxidant found within
every cell of our body, is in particular critical within the lens of
our eye and the pigment and the photoreceptor cells of the
retina. The level of glutathione declines when we get older.

Glutathione peroxidase is one of the natural antioxidant
defencesystems that our body creates. The nutrients needed
for the body to make its own defense are selinium, vitamin B6,
N-acetyl-L-cysteine and niacin.

Vitamin C and alpha-lipoic acid have the ability to regenerate
glutathione. Zinc is important for the function of our catalase
antioxidant defense system and selinium is necessary for the
glutathione peroidase system and both are important to
combat free radicals produced in the eye.

As we get older, the lens of our eyes allows more ultraviolet
light through and no longer protects the retina from damage
of ultraviolet light. A good quality pair of sunglasses that
block all UV light are important.

Without any doubt, the underlying cause of cataracts and
macular degeneration is oxidative stress.
Consequently, we can’t be too agressive in our
supplementation plan.