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Letter from Dr. Janson
Preserving Eyesight—Start with
Diet
Add Exercise for Circulation
Ultraviolet protection
Supplements that help the eyes
A supplement program for eyesight
More on Lycopene
Natural Remedies for Diabetes
In the Health News
By the Way:
References
Dear Friends,
One of the most common questions I hear in my medical practice
is “What can I do with nutrition to improve my vision
or prevent loss of eyesight.” Indeed, loss of vision
is the most feared disability, and many of the problems that
lead to visual loss are related to lifestyle choices. Whether
your concern is cataracts, macular degeneration, diabetic
or hypertensive retinopathy, changing your lifestyle will
make a difference.
Vision depends on a clear lens, the rich microcirculation
to the retina, and the visual nerve cells of the retina called
rods and cones. All of these can deteriorate with age, depending
on exposure to toxins and oxygen free-radicals, poor dietary
habits, hardening of the arteries, and high blood pressure.
Diabetes leads to retinal disease because of damage to the
retinal arteries and to cataracts because of high blood sugar
levels.
First, eat a healthy diet with an emphasis on fresh
vegetables and fruits, plus whole grains, beans, seeds, and
nuts. The vitamins, minerals, essential fatty acids, and phytochemicals
that they provide are important for overall health as well
as the eyes. If you wish, add a small amount of organic, lowfat
yogurt, organic eggs, and a small amount of fish (unfortunately,
it is increasingly difficult to find wild fish due to the
widespread use of factory-style fish farming—including
the use of antibiotics and other drugs, and genetically engineered
growth hormone to increase growth rates). Dairy products contain
the milk sugar—lactose, a combination of two simpler
sugars, glucose and galactose. Both glucose and galactose
are converted through the action of an enzyme called aldose
reductase to “sugar-alcohols,” which can cause swelling
of the lens. They also attach to proteins that then deposit
in the lens. Both the lens swelling and the sugar-protein
deposits lead to cataracts.
To avoid these sugar-protein combinations, in addition to
reducing milk-product consumption, it is wise to keep all
added sugars out of the diet. This means avoiding those addictive
sweets—such as the average of two doughnuts per person
per day that Americans eat, along with the sodas, cookies,
pies, ice cream, and candy. In fact, the American diet is
a prescription for disaster when it comes to your eyesight
(and many other health issues). Staying with a mostly vegetarian
diet of natural, unpro-cessed foods will help preserve the
circulation to the retina, the rods and cones, and the lens.
Second, exercise regularly. It helps to maintain a low blood
pressure (I’ll talk specifically about managing blood
pressure in a future issue) and preserves the blood vessels
(the retina is rich in small blood vessels). Exercising for
45 minutes lowers blood pressure for an additional 16 hours
after finishing. Exercise also helps to support the health
of the cells that line the arteries, called endothelium. These
cells help relax the blood vessel muscle and maintain blood
flow—another benefit is improved circulation to the heart
through the coronary arteries.
The eyes are subject to a lot of oxidative damage to
both the lens and the retina because they are exposed to ultraviolet
light and a rich circulation of oxygen from the dense retinal
capillaries. Protecting the eyes from too much sun exposure
may help delay any degeneration of the lens and the retina.
This does not mean avoiding all sunlight. Some sun exposure
is healthy as long as it is in moderation, and not enough
to tan or burn the skin. The action of sunlight on the skin
is important for the production of vitamin D, and light stimulates
the pineal gland, suppressing melatonin production during
the day. UV-filtering lenses may provide some protection for
the eyes, if they actually do what they claim.
Many dietary supplements support eye health . They
improve vision and help protect the macula (the area of the
retina with the sharpest vision) and the lens. The usual antioxidants
such as vitamins E and C, and the trace minerals selenium
and zinc help the retina and the lens. High levels of vitamin
E can reduce cataracts by 60 percent. Other helpful nutrients
are the amino acid taurine, carotenoids such as beta-carotene,
lycopene (found in tomatoes), and lutein (from spinach and
kale), and the anthocyanosides (related to bioflavonoids)
found in grapes and blueberries (or bilberry, the European
variety). Bilberry may improve night vision, as the anthocyanosides
enhance the activity of the rods and cones. It also helps
strengthen the retinal blood vessels in diabetic retinopathy.
Other nutrients also play a role. Glutathione, made from
the amino acid cysteine, participates in the chain of reactions
that control free radicals and helps to regenerate vitamin
E. It is part of an enzyme called glutathione reductase that
depends on vitamin B2 (riboflavin).
Recent evidence shows that both lutein and lycopene play a
role in eye protection. Lutein is present in the lens, suggesting
an antioxidant role in cataract prevention. In one study,
people with low levels of lycopene were more than twice as
likely to have macular degeneration compared to those with
the highest levels. Another study supports the role of lutein
in prevention of macular degeneration.
For a complete supplement program for the eyes, especially
as you get older, I recommend starting with a comprehensive
multivitamin mineral. To that, add daily doses of vitamins
C (at least 3000 to 4000 mg) and E (400 to 800 IU), bilberry
(200 mg), lutein (10 to 20 mg), and lycopene (10 to 20 mg).
I also think it is a good idea to take ginkgo biloba (120
mg of standardized extract), which helps the circulation in
small blood vessels and has been shown to protect the retina,
taurine (500 to 1000 mg), and N-acetyl-cysteine (100 to 200
mg), also important for retinal cells. Quercetin is a bioflavonoid
that blocks the sugar-alcohol formation from glucose and galactose.
If you recall, these molecules lead to swelling of the lens,
contributing to cataracts. Usually 400 to 800 mg daily is
an adequate dose.
Put this entire program together, and you are likely to maintain
your vision well into advanced years, and you may well reverse
some of the damage that has already been done.
Lycopene is valuable for more than just your eyes. Research
shows that it helps men with prostate cancer for both prevention
and in reducing the spread of the cancer. In men given 30
mg of lycopene daily for just three weeks before prostate
surgery, their tumors were already smaller than in the controls.
Also, the cell markers for cancer growth were decreased, and
biomarkers of cancer cell death were increased.
The evidence is also strong that lycopene helps prevent cancers
of the lung and stomach, and it is suggestive for tumors of
the pancreas, colon, rectum, esophagus, mouth, breast, and
cervix, so both men and women will benefit from taking it.Lycopene
also protects LDL-cholesterol (the "bad cholesterol")
from oxidation. Oxidized LDL damages the arteries, so lycopene,
from food and supplements (along with other antioxidants,
B vitamins, coenzyme Q10, and magnesium) is a great nutrient
for heart protection, as well as cancer prevention and treatment,
and vision.
I suggest that you eat tomato products and consider supplements
of 10 to 30 mg of lycopene.
Diabetes mellitus, or sugar diabetes, is a failure to properly
metabolize sugar, specifically blood glucose. It results from
either the reduced function of the pancreas, which produces
insulin, or more commonly, from the inability of the cells
to respond to insulin, called insulin resistance. Insulin
is essential to move sugar into the muscles, where it can
be burned for energy.
Adult onset diabetes (Type II) is almost always the result
of poor health habits and being overweight. Insulin and oral
medications are usually unnecessary if you exercise regularly,
take your supplements and eat the right diet—high fiber,
complex carbohydrates, low fat, and mostly vegetarian—these
foods control blood sugar and provide essential phytonutrients.
The long-term complications of diabetes include retinopathy,
cataracts, hardening of the arteries, and diabetic neuropathy—nerve
degeneration with numbness and tingling starting in the feet
and legs. Diabetes can often be reversed and the complications
treated and prevented with lifestyle changes and specific
dietary supplements.
Even Type I diabetics can reduce their insulin doses with
a complete approach to blood sugar management. However, medical
supervision of diabetes is usually essential, and I do not
recommend trying to manage diabetes by yourself.
Numerous supplements help diabetes. Unrelated to normal
nutritional levels, it is often necessary to take high doses
of the trace mineral chromium, up to 1000 mcg per day, to
regulate blood sugar, because diabetics are resistant to its
effects. Chromium improves insulin activity and lipid levels,
and it is depleted by the fatty, sugary American diets that
are now spreading around the world.
The essential fatty acid GLA (gamma-linolenic acid), derived
from borage oil or primrose oil, can treat diabetic peripheral
neuropathy. The typical dose is 240 mg, from 1200 mg of borage
oil or 3000 mg of primrose oil.
In a previous newsletter I mentioned the value of the antioxidant
alpha-lipoic acid. While as little as 100 to 300 mg daily
might be adequate as a potent antioxidant, 600 mg will improve
blood sugar control, and 1000 mg daily can reverse diabetic
neuropathy(even better along with GLA).
These are in addition to your B complex, extra vitamins C
and E, coenzyme Q10, minerals, and all the other nutrients
that help eyesight.
•Physical activity appears to confer benefits to post-menopausal
women that goes beyond the help with bone density. Women who
get regular moderate to vigorous exercise more than four times
a week are half as likely to get diabetes as those who do
not exercise. Even less exercise, as long as it is regular,
reduces the risk of diabetes by about 30 percent. Of course,
diet also helps by maintaining a normal weight, and high fiber
helps to control blood sugar—even in those who are already
diabetic, a vegetarian diet of unprocessed, high-fiber foods
helps.
•Recent studies show that aspirin has side effects of
kidney and gastrointestinal damage, even if taken in the low
doses recommended to reduce platelet aggregation for prevention
of heart disease. This is disappointing to some physicians,
but effective alternatives to aspirin are probably better
anyway. Vitamin E, garlic, ginkgo biloba and other herbs,
and the essential fatty acids in fish oil, flaxseed oil, and
borage oil (GLA) will have the same effects without any of
the potential side effects. These seem like a better choice.
•Yet another article supports the value of a diet
high in vegetables. Researchers report that cruciferous vegetables,
such as broccoli and cauliflower, dramatically reduce the
risk of prostate cancer. For those men who ate more than 28
servings of vegetables a week, the risk was reduced by 35
percent. If they ate at least three servings of cruciferous
vegetables a week, the risk was reduced by 41 percent. These
contain isothiocyanate, a phytochemical that helps detoxify
carcinogens.
I just attended a conference on genetically modified foods,
once again confirming that there is little safety data to
support the increased farming of these crops. In addition
to the unknown risks to human health when genes are inserted
from one species to another, it creates a risk to the environment,
a risk to other species, such as butterflies and bees, and
possible changes in the genetic makeup of native plants. The
agribusinesses that are selling these seeds couch their deception
by saying there is "no evidence of harm" when what
they mean is they have no data at all! They could just as
well say they have no evidence of safety, but that wouldn't
sell products.
Am J Hypertens 2000;13:44-51.
Hambrecht R, et al., Effect of exercise
on coronary endothelial function in patients with coronary
artery disease. N Engl J Med 2000 Feb 17;342:454-460.
Travis G, et al., Cell 1999;98:13-23.
Mares-Perlman JA, et al., Serum antioxidants
and age-related macular degeneration in a population-based
case-control study. Arch Ophthalmol 1995 Dec;113(12):1518-23.
Snodderly DM, Evidence for protection against
age-related macular degeneration by carotenoids and antioxidant
vitamins. Am J Clin Nutr 1995 Dec;62(6 Suppl):1448S-1461S.
Giovannucci E, Tomatoes, tomato-based
products, lycopene, and cancer: review of the epidemiologic
literature.J Natl Cancer Inst 1999 Feb 17;91(4):317-31.
Gann PH, et al., Lower prostate cancer
risk in men with elevated plasma lycopene levels: results
of a prospective analysis. Cancer Res 1999 Mar 15;59(6):1225-30.
Agarwal S, Rao AV, Tomato lycopene
and low density lipoprotein oxidation: a human dietary intervention
study. Lipids 1998 Oct;33(10):981-4.
Riales R, Albrink MJ, Effect
of chromium chloride supplementation on glucose tolerance
and serum lipids including high-density lipoprotein of adult
men. Am J Clin Nutr 1981 Dec;34(12):2670-8.
Anderson RA, Chromium, glucose intolerance
and diabetes. J Am Coll Nutr 1998 Dec;17(6):548-55.
Jacob S, et al., Oral administration
of RAC-alpha-lipoic acid modulates insulin sensitivity in
patients with type-2 diabetes mellitus: a placebo-controlled
pilot trial. Free Radic Biol Med 1999 Aug;27(3-4):309-14.
Folsom AR, et al., Physical
activity and incident diabetes mellitus in postmenopausal
women. Am J Public Health 2000;90:134-138.
Cohen JH, Kristal AR, Fruit and vegetable
intakes and prostate cancer risk. J Natl Cancer Inst 2000
Jan 5;92(1):61-8.
Cryer B, Feldman M, Effects of very low
dose daily, long-term aspirin therapy on gastric, duodenal,
and rectal prostaglandin levels and on mucosal injury in healthy
humans. Gastroenterology 1999 Jul;117(1):17-25.
Caspi D, et al., The effect of mini-dose
aspirin on renal function and uric acid handling in elderly
patients. Arthritis Rheum 2000 Jan;43(1):103-8.
drjanson@drjanson.com
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through May: 386-409-7747
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through October: 603-878-2256
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