by Roger French
The possibility of going blind is a thought that fills most people with
dread. Because it is generally believed that cataract of the eye and
glaucoma are a matter of bad luck, the perception is that there is little
we can do to prevent them. However, this is not the case. A study of
the recent medical literature reveals that for cataract the causes have
been largely identified, and for glaucoma there are clear indications
of the likely causes.
Almost all the underlying causes of both conditions are related to lifestyle.
This is fortunate because lifestyle can be modified, which means that
each of us has some measure of control over whether or not these problems
develop.
Firstly, it is appropriate to look at a little background information
on cataract and glaucoma. Cataract, which afflicts 50 million people
worldwide, is the leading cause of blindness in the human race, followed
by glaucoma. The impact of these diseases provides an enormous public
health problem in both developing and industrialised countries, not
to mention the suffering involved.
Age-related (or senile) cataracts tend to affect people over 65, the
incidence between 65 and 75 years of age being around 1 in 6 persons,
while in the 75 to 85 year bracket, it’s almost every second person.
Glaucoma also affects older people, and is more common in women than
men. The standard treatment for cataract is surgery, which is often
successful, whereas there is no medical cure for glaucoma, which often
gets worse even when the person is being treated.
What Cataract and Glaucoma Are
Cataract means loss of transparency of the lens of the eye and/or its
capsule, resulting in partial or total blindness. The lens becomes clouded
or opaque and is unable to transmit light properly or to focus. The
opacity is the result of precipitation of proteins or other constituents
of the lens. Because the proteins in the lens are unusually long-lived,
they are subject to extensive damage if harmful effects are ongoing.
Glaucoma is a serious disease characterised by abnormally high pressure
in the fluid within the eyeball, which may eventually damage the retina
(the light-sensitive membrane lining the inside of the eyeball) and
ultimately destroys the optic nerve, resulting in loss of vision and
then total blindness. In some cases, the intraocular pressure is normal,
but there is poor circulation, resulting in damage to the optic nerve.
(1)
There are two types of glaucoma - closed-angle glaucoma and open-angle
glaucoma.
The closed-angle type presents itself as an acute and severe problem
caused by narrowing or hardening of the exit channels from the eyeball
through which the fluid that fills the inside of the eye can escape
as it is meant to do. During the attack, the person is likely to experience
throbbing eye pain, reduced vision, especially peripheral vision (what
you see at the edges of your field of view), mildly dilated pupils,
and occasionally nausea and vomiting. This form of glaucoma can permanently
impair vision in a matter of days. Fortunately, it is not so common.
Chronic open-angle glaucoma is the more common form. Although there
is no physical blockage of drainage, some physical defect in the ‘trabecular
meshwork’ restricts drainage and the intraocular pressure rises.
A problem with this condition is that there are usually no symptoms
until very late in its development, by which time vision may be irreversibly
damaged. The usual symptoms are loss of peripheral vision (‘tunnel
vision’) and decreased night vision. There may also be chronic
mild headaches and seeing halos around electric lights.
The Causes of Cataract and Glaucoma
The causes of these two conditions appear to be substantially different,
although among the factors listed by the researchers there is some overlap.
When we trace these causes back to their origins in lifestyle, we find
still more overlap. In the meantime, we will look at each disease separately.
Cataract
A long list of risk factors is given by the Virginia State University,
USA, (2) and also the University of California (3), and to this list
has been incorporated a number of factors from other researchers. The
wide-ranging list is as follows:
Being older. (Age does not cause cataract, rather harmful effects have
had time to do more damage):
Oxidation of lens tissue due to free-radical attack Trauma (injury)
Inflammation within the eye Pharmaceutical drugs Steroid drugs (such
as cortisone) are significant risk factors Radiation - ultraviolet B
and X-ray, etc. - is an important risk Dehydration is a possible contributor
Nutritional deficiencies, especially of antioxidant nutrients Heavy
metal toxicity, especially of cadmium Obesity, defined as more than
20% overweight, is a major risk factor Excessive calorie intake, which
contributes to obesity and other risks Diabetes increases the risk three
to four times Galactose build-up due to high consumption of dairy products
combined with inability to process galactose Smoking Alcohol High blood
pressure.
Free Radical Attack and Oxidative Stress
Free radical attack is the basis of the mechanism of cataract formation.
For glaucoma, the researchers only give mild indications that free radicals
may be partly involved. Let us first take a brief look at free radicals.
Although perceived as agents of mischief, free radicals - reactive oxygen
species - were involved in the evolution of life and are virtually ubiquitous
in living things, being formed during normal cell metabolism. The body
has an elaborate defence system against free radicals, and it is only
when there is an imbalance between their generation and the body’s
defences that there results a surplus of free radicals able to do damage.
These can manifest as degenerative diseases that include cancers, atherosclerosis, rheumatoid arthritis, Crohn’s disease, ulcerative colitis and cataract.
The all-important question is, what causes free radicals? The Japanese
Niwa Institute for Immunology (5) reports that free radicals are produced
by environmental toxic agents. These include.
Herbicides such as paraquat; Insecticides; Nitrogen oxide, a prominent
component of motor vehicle exhausts; Ultraviolet radiation; PCBs (polychlorinated
biphenyls); Heavy metals, including methyl mercury, manganese and cadmium.
Other prominent generators of free radicals include free iron, chlorine
in drinking water and a number of other synthetic chemicals.
The body’s defences against oxidative injury by free radicals are
based on enzymes that include glutathione peroxidase, superoxide dismutase
and catalase, and on antioxidant nutrients, particularly vitamins C,
E and A, the carotenoids from which vitamin A is made, polyphenols,
flavonoids and catechins. In fresh vegetables and fruits there is also
a myriad of other antioxidants that fall under the general label of
phytochemicals.
Glutathione attracts much attention because it destroys surplus free
radicals in the body. Thorne Research Inc, Dover, USA, has concluded
that deficient glutathione levels within the lens of the eye contribute
to cataract formation. Nutrients that increase the levels of glutathione
include vitamins E and C, selenium, lipoic acid and vitamin B2 (riboflavin).
(6)
Glaucoma is also linked to compromised antioxidant defences by Thorne
Research Inc., which states that, like patients with cataracts, people
with glaucoma typically have compromised antioxidant defence systems.
In cataracts, extensive evidence of oxidative damage has been detailed
by the Department of Ophthalmology, Dokkyo University School of Medicine
in Japan. (7) In cataractous lenses they found decreased activity of
antioxidant enzymes, increased oxidation of lipids and lipoproteins
and a marked decrease in the ability to scavenge oxygen radicals, as
well as ongoing generation of free radicals within the lens. Ions of
the potentially oxidising metals, iron and copper, were found in lens
tissue, and the researchers related this to the increased oxidation.
An interesting consequence of oxidation was increased saturated fatty
acids in the lenses.
The reactive oxygen species that initiate lipid peroxidation are superoxide
(O2-), hydrogen peroxide (H2O2) and hydroxyl radical (OH).
Ultra Violet Rays on the Eyes
Data from the US National Health and Nutrition Examination Survey suggested
that total exposure to sunlight is significantly related to cataract.
(8) Polish researchers in 1997 suggested that it is, in fact, the main
factor leading to age-related cataract. (9) They say that UVB and visible
light generate free radicals in the lens. However, in the year 2000,
the Eye Research Laboratory, Boston, USA, concluded that UVA may be
the more damaging radiation for cataracts, as it also, though indirectly,
appears to generate free radicals. (10)
The mechanism of UV damage remains unclear because there is very little
oxygen in the lens, so oxidants may not be able to exert their harmful
effects. Nevertheless, the radiation appears to cumulatively damage
lens DNA and proteins and to generate damaging oxidants through interaction
with iron compounds.
Smoking Has Multiple Effects
There is a strong association between smoking and a number of common
eye diseases, including cataract and glaucoma. (11) Not surprisingly,
the more smoking, the greater the risk.
The main contributing forms of damage are artery disease (atherosclerosis)
and blood clots in the capillaries of the eye, the generation of free
radicals and decreased levels of antioxidants. Thus, smokers have much
greater risks of having free radical damage and oxidation than non-smokers.
Strict Vegetarian Diet
An English study that compared Asians to Caucasians living in the City
of Leicester found that age-related cataract was significantly more
common in the Asians, and that a strict vegetarian diet was a significant
risk factor for such cataracts in the Asians. (12)
It is postulated by the writer that the problem with the strict plant
diet may be vitamin B12 deficiency which is more common when no animal
products are consumed. This emphasises the importance for people on
strict plant diets of having vitamin B12 levels checked periodically.
‘Sugar’ Cataracts
Cataract associated with diabetes and galactose build-up are categorised
by their rapid onset. They are known as ‘sugar’ cataracts,
because in diabetes the level of blood sugar (glucose) is high, while
in galactosaemia the level of the sugar, galactose, derived from diary
products, is at excessive levels.
The mechanism common to both types is the conversion of either glucose
or galactose to sugar alcohols (or polyols) by an enzyme called aldose
reductase. (13) The process produces oxidative stress, while the build-up
of sugar alcohols causes osmotic pressure, leading to swelling of the
lens and subsequent opacity.
For the technically-minded, aldose reductase is associated with the
conversion of glucose to the sugar alcohol, sorbitol, and is found in
the cornea, retina and lens of the eye, the kidneys, the myelin sheaths
surrounding nerves and in some other tissues. Significantly, it is only
when blood sugar level is high that this enzyme is activated, leading
to the production of sorbitol. Conversely, if blood-sugar level is normal,
there will be no cataracts associated with blood sugar.
The best-selling natural therapies text, Prescription for Nutritional
Healing, (1) states that while free radicals are probably the major
factor in the increasing number of cataracts, the single greatest cause
is the body’s inability to cope with food sugars. Galactose is
the worst offender, followed by refined white sugar.
The text adds, “Many eye specialists note that most people with
cataracts eat diets that include substantial amounts of dairy products
and refined white sugar.”
Heavy Metals
The above text states that heavy metals increase in concentration in
the lenses of both older people and those with cataracts. In particular,
cadmium is found at levels two or three times higher than normal in
cataract lenses.
Cadmium is one of the consequences of the use of superphosphate fertiliser
in food production. The problem is exacerbated by the refining of flour
because the cadmium remains in the white flour, while the protective
zinc is milled away with the bran and wheat germ.
Glaucoma
Not as much is known about the causes of glaucoma as of cataract. The
literature mentions family history of glaucoma, age and obesity as risk
factors.
Family history implies not only a genetic predisposition to a disease,
but also ‘inheriting’ the diet and lifestyle of the parents,
grandparents, etc. Even so, where there is a genetic predisposition,
it is usually mutations of the inherited gene that are associated with
the disease.
The Department of Ophthalmology of the University of Iowa, USA, found
that mutations of the relevant gene cause most cases of juvenile-onset
chronic glaucoma and around 5% of adult-onset cases. (14)
Individuals have no control over inheriting particular genes, but we
can reduce the likelihood of mutations occurring - by avoiding toxic
chemicals and excessive calorie intake.
Restricted Blood Flow
Swedish ophthalmologists suggest that the primary cause of glaucoma
might be progressive increase in flow resistance in the veins in the
eye. (15) This ischaemia (lack of blood), combined with impaired nutrition,
starts off the glaucoma.
The elevated intraocular pressure (IOP) is the result of narrowing or
hardening of the exit channels through the trabecular meshwork that
was referred to earlier. The cause of this narrowing or hardening appears
to be not dealt with by the researchers.
The actual cause of diminished vision or blindness is thought to be
the result of ischaemia damaging the optic nerve. The pressure in the
eyeball reduces the flow in the veins, producing the ischaemia. Other
likely causes of ischaemia are atherosclerosis or blood clots in the
capillaries of the eyes. As this is the same process that occurs in
the coronary arteries of the heart and causes heart attack, so the same
lifestyle factors that prevent heart attack can be expected to prevent
at least one possible cause of glaucoma. The ischaemia theory was proposed
by the Department of Ophthalmology of the University of Miami in 1999.
(16)
It appears that there is a vicious circle acting here. Diseased capillaries
in the eye restrict the flow of blood which damages and blocks the drainage
channels for the fluid in the eye (aqueous humor). This creates pressure
in this fluid which in turn presses on the veins and further restricts
blood flow. More damage is done to the drainage channels, the escape
of fluid is even further restricted and its pressure climbs. The spiralling
ischaemia eventually damages the optic nerve and hence impairs vision.
Vitamin B1 Deficiency
An early study of patients with glaucoma found that they had significantly
lower blood levels of thiamine (vitamin B1) than people without glaucoma.
(17)
In view of the general association between B vitamins and nerve function,
this finding is understandable.
Smoking
As was stated in the discussion on cataract, there is a strong association
between smoking and eye diseases, including cataract and glaucoma. (11)
Smoking generates free radicals in many parts of the body, including
the aqueous humor and other tissues of the eye. It may well be that
free radical damage is part of the mechanism for the development of
glaucoma.
Diabetes
Whatever mechanism is involved, glaucoma is found to be more prevalent
in diabetic people than non-diabetic people. (18)
Preventing Cataract and Glaucoma
Cataract
To prevent the occurrence of oxidative injuries that lead to cataract
(and also cancer, artery disease, Alzheimer’s disease, Parkinson’s
disease and others), the body has a powerful self-defence system hinged
on a wide range of antioxidants. (5) These include:
Enzymes, particularly glutathione peroxidase, superoxide dismutase and
catalase. Nutrients, particularly vitamins C, E and A and carotenoids,
flavonoids, polyphenols and catechins.
The carotenoids particularly needed by the lens are lutein and zeaxanthin
Vitamin B2, or riboflavin, (not an antioxidant) is essential for the
production of glutathione.
Cataract patients tend to be deficient particularly in vitamin A, lutein
and zeaxanthin.
Because of the prominence of glutathione in destroying free radicals,
researchers have investigated which nutrients support the body’s
production of this enzyme. They are vitamins C and E, selenium (part
of the structure of glutathione) and lipoic acid. (6)
Other nutrients that benefit cataract suffers include vitamin B5 (pantothenic
acid), vitamin B9 (folic acid), melatonin and the herb bilberry.
This defence system also exists within the lens itself, the lens containing
the three enzymes mentioned above plus vitamins C and E and the carotenoids.
(19)
Vegetables and Fruit
A number of population studies have found that there is a reduced risk
of developing cataract and other diseases in people who have high intakes
of vegetables and fruit. (4) Not only do these contain vitamins C and
E and carotenoids in their perfectly natural forms, but they contain
a myriad of other antioxidants, alkaline minerals and other beneficial
nutrients.
As researchers are realising more and more the far-reaching health benefits
of vegetables and fruit, they are conducting an increasing number of
studies of these foods. In year 2000, the National Cancer Institute
of the USA published an overview of the health benefits of fruit and
vegetable consumption. (20) The report stated, “A new scientific
base is emerging to support a protective role for fruits and vegetables
in prevention of cataract formation ...”
The National Cancer Institute recommended increased consumption of a
wide variety of vegetables and fruits, in particular, dark-green leafy
vegetables, cruciferous vegetables and deep-yellow-orange vegetables,
as well as a wide variety of fruits, in particular, citrus and deep-yellow-orange
fruits.
Antioxidant Supplements
It has been found that populations with higher blood levels of antioxidants
have reduced incidences of cataracts. (19) Also, vitamin E has been
found to be effective in arresting the developing of cataracts in animals.
Consequently, there has been a lot of interest in whether supplements
might prevent cataracts.
A 1994 Danish review of studies concluded that there is no evidence
that antioxidant supplements would provide protection against cataract
(or cancer, or atherosclerosis). (4) A new study of supplements in relation
to cataract was conducted by the School of Public Health at the University
of Massachusetts in 1999. It looked at 74,000 women, aged 45 or older,
in whom there developed 1377 age-related cataracts. (21) It was found
that taking multi-vitamins or separate supplements of vitamins C, E
or A did not reduce the risk of cataract, and only in specific groups
was there any benefit, namely long-term vitamin C users who had never
smoked, and in the women less than 60 years of age. The two groups had
modest reductions in cataract incidence. The researchers concluded that,
“there is little overall benefit of long-term use of vitamin supplements
for risk of cataract.”
Clearly, something very significant is showing up here. With abundant
evidence that antioxidant nutrients are protective, yet little if any
benefit being found in taking antioxidant supplements, either a wider
range of nutrients than just a few supplements is needed, or else the
supplements are not as effective as the food sources of nutrients.
Shedding some light on this question, the Japanese Niwa Institute for
Immunology reported that synthetic antioxidant nutrients “generally
showed low affinity to human cell receptors.” (5) In other words,
the body’s ability to use synthetic vitamins is poor, and the natural
sources are therefore far superior.
Plenty of Vitamin C is Needed
Vitamin C has many functions besides collagen formation to prevent scurvy.
It increases the absorption of inorganic iron, has an essential role
in the metabolism of folic acid, some amino acids and hormones, and
is an important antioxidant.
There is evidence that we need much more vitamin C than the Australian
recommended daily intake of 30 mg for women and 40 mg for men that prevents
scurvy. The Linus Pauling Institute, Oregon, USA, concluded that an
intake of 90 to 100 mg per day is required “for optimum reduction
of chronic disease risk in non- smoking men and women.” The Institute
proposed that the RDI be increased to 120 mg/d. (22)
Other researchers point out that for smokers the requirement is higher
by at least 60 mg/d.
With regard to the safety of taking supplements of the main antioxidant
vitamins, the International Antioxidant Research Centre, Guy’s
Hospital, London, found that they have wide margins of safety. (23)
Vitamin C is safe at least up to 600 mg/d and probably even up to 2000
mg/d. Vitamin E has very low human toxicity and an intake of 1000 mg/d
is without risk, says the Research Centre. Even 3200 mg/d has been shown
to be without any consistent risk. However, regarding beta carotene,
large intakes must be viewed with caution because they have been found
to be detrimental to smokers having a high risk of lung cancer.
Sun Protection
Against cataracts induced by sunlight, both blood levels and dietary
intake of antioxidants have been found to be protective to some degree.
Vitamins C and E were found to be significantly protective, (19) the
polyphenols in tea (especially the catechins in green tea) provide some
protection,(10) and sunglasses with ultraviolet filters are also useful.
(9)
Preventing the Development of Sugar Cataracts.
Recalling that the enzyme, aldose reductase, is critical to the development
of sugar cataracts, it has been found that if this enzyme is inhibited,
cataracts will not develop. (13) Potent inhibitors of this enzyme are
the nutrients, flavonoids, especially quercetin, which are water-soluble
phytonutrients occurring ubiquitously in plants, some being strongly
antioxidant. (24) They are abundant in foods like cranberries, green
tea, beetroot, elderberries, raspberries, blueberries, red and black
grapes and citrus fruits.
According to Prescription for Nutritional Healing, (1) flavonoids aid
in removing toxic chemicals from the eye, a particularly rich source
being bilberry extract.
To prevent diabetes in the first place, the first requirement is a low-fat
diet, which needs to be essentially vegetarian. To avoid the risk of
galactosaemia, reduce dairy products to low levels.
Preventing Glaucoma
Antioxidants
The body of research on glaucoma is much smaller than for cataract,
reflecting the fact that the causes and preventative steps for glaucoma
are much less understood than they are for cataract.
However, it has been found that glaucoma sufferers typically have compromised
antioxidant defence systems just as do cataract sufferers. (6) Therefore,
most of what has been said about strengthening antioxidant defences
to prevent cataracts can also be applied for the prevention of glaucoma.
Calorie Restriction
The effects of calorie restriction on the eye drainage channels was
studied in mice at the University of Washington in 1997. (25) ‘Calorie
restriction’ in animals or humans means that all essential nutrients,
including calories, are adequately supplied in the diet, but there is
no surplus of nutrients above needs for normal function - as happens
when animals (and humans) are allowed free access to food. When the
mice reached ‘old age’, those allowed free access to food
had drainage channels that had reduced in area by 34% or approximately
one-third.
The researchers concluded that there is a possible role for life-long
calorie restriction in reducing the damage that leads to glaucoma and
perhaps delaying its development.
For Both Cataract and Glaucoma - Minimising
Free Radical Damage
Minimise exposure to pesticides, herbicides and other toxic synthetic
chemicals. Obtain organically-grown foods if possible, grow your own,
or at least wash commercial fruits and vegetables with a safe ‘organic’
cleanser. Avoid chlorine by purifying tap water or drinking bottled
or rainwater. Avoid exposure to industrial chemicals, especially solvents.
Avoid tobacco smoke, a powerful generator of free radicals. Be cautious
with medical drugs that might lead to cataract. Especially avoid steroids
such as cortisone if at all possible.
Minimise exposure to radiation, especially X-rays. Wear sunglasses when
outdoors in bright sunlight.
Minimise cadmium intake by eating organically-grown foods. Avoid consuming
rancid (oxidised) fats, likely to be found in deep-fried foods, biscuits,
cakes, pastries, vintage cheese, cured meats, long-stored peanut butter,
stale shelled nuts and seeds and so on. Avoid surplus iron. Never take
iron supplements unless there is iron deficiency, and beware of the
more readily available iron in red meat.
For Cataract and Glaucoma - Abundant Antioxidants
To obtain much higher levels of antioxidant nutrients and less calories
than in the typical modern diet, follow Natural Health Dietary Guidelines.
These are presented in detail in the Spring 1999 issue of New Vegetarian
and Natural Health, pages 54 - 60.
These guidelines are based on three-quarters of total intake being fresh,
green, yellow and red vegetables and fruits, meaning approximately three-quarters
to one kilogram daily for a person of average size. More for larger-framed
people and less for smaller-framed people. Along with minimising exposure
to toxic chemicals, a high intake of these highly protective foods are
the major things we can do to prevent cataract (as well as a host of
other diseases, including heart disease, stroke and cancer).
Fresh vegetables and fruits are the only abundant and ideal sources
of vitamin C, carotenoids (from which we make vitamin A), flavonoids,
other antioxidants and a host of other phytonutrients. They are also
the outstanding sources of the alkaline minerals, potassium, magnesium
and calcium, as well as many trace minerals.
The dietary guidelines also include small but regular amounts of legumes,
nuts and seeds, supplying high levels of vitamin E, zinc - and selenium
if we include a few Brazil nuts frequently.
For Cataract and Glaucoma - Problem Medications
Along with steroids increasing the risk for cataract, there are other
medications that have side effects that affect the eyes. For this reason,
avoid unless absolutely necessary antidepressants, anti-epileptic drugs,
topical anti-glaucoma agents and chemotherapy/immunosuppressive agents.
Some of the side effects of these drugs are reversible and some are
not. (26)
Help for Existing Cataract and Glaucoma
There is no medical cure for either cataract or glaucoma, and with glaucoma
any damage to vision is irreversible.
Cataract
With cataract, vision can be restored by surgery which replaces the
opaque lens with a prosthetic lens implant. Although this is a fairly
common and often successful operation, apparently some patients are
dissatisfied with the result. Prescription for Nutritional Healing(1)
concludes, “We believe that surgery should be resorted to only
when absolutely necessary - when your natural lens becomes so opaque
that you cannot read or drive.”
It is probable that there is nothing in natural therapies either that
can reverse existing cataract. However, if there is still some level
of vision, the steps given under ‘Prevention’ above may prevent
the cataract progressing any further. This could obviously be a great
benefit compared to progressing to blindness.
Glaucoma
For glaucoma, medical treatment aims at reducing the irreparable damage.
However, as recently as 1999, medical treatment for glaucoma attracted
extraordinarily disparaging remarks from the Wills Eye Hospital in Philadelphia,
USA. (27) It was stated, “In the recent past, far more damage was
caused by treatment for glaucoma than by glaucoma itself. To repeat
... glaucoma and its treatment damage health more than any other eye
disease except cataract, and the medical profession is responsible for
a major part of that problem.” This strongly suggests that natural
therapies is the better way to go.
The following guidelines are taken from Prescription for Nutritional
Healing(1) and a paper entitled ‘Natural Therapies for Ocular Disorders’.
(6)
Vitamin C in high doses has been found to lower intraocular pressure
via its osmotic effect. This is the most documented natural treatment
for glaucoma. Almost normal pressure levels have been achieved in some
people who did not respond to orthodox therapies. A valuable natural
source of vitamin C is rose hips, which also supplies flavonoids.
Increase the intake of flavonoids (or bioflavonoids) which prevent the
breakdown of vitamin C, improve the integrity of blood capillaries and
strengthen the tissues of the eye. They are found in the peel and outer
layers of fruits and vegetables, including leafy vegetables, red onions,
beetroot and red and blue berries. The readily available herb, bilberry
extract, is particularly rich in these nutrients.
The herbs, eyebright and chickweed, are good for all eye disorders.
Ginkgo biloba increases the circulation to the optic nerve, which would
be especially helpful.
Forskolin, an extract from a plant named Coleus forskohlii, has been
successfully used to lower intraocular pressure without causing side
effects.
Other nutrients that have potential benefit include magnesium, vitamin
B12, lipoic acid and the hormone melatonin. Lipoic acid acts as an antioxidant
by enhancing the properties of vitamins C and E and glutathione. Food
sources include potato and yeasts, and it is available as a supplement.
Hydrotherapy promotes circulation. Have two bowls, one filled with hot
water and the other with very cold (not icy) water. Soak a washer in
hot water, wring lightly and place over the eyes for 3 minutes. Have
a second washer in the cold water, wring lightly and place over the
eyes for 1 minute. Repeat twice more, making three cycles of hot and
cold altogether.
Avoid long periods of eye stress, such as watching television, reading
or using a computer for long periods. If you must do these things, take
breaks every 20 minutes to flex and stimulate the eyes by focussing
alternately on a distant object then a close object for a few minutes.
Avoid nicotine, caffeine and alcohol which can interfere with the circulation
to the eyes.
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