Driving during the darker hours of the day can be difficult when
you have night blindness. According to research or other evidence, the following self-care
steps may help improve your vision in low light:
Get a nutritional checkup
Visit a knowledgeable professional to find out whether your night
blindness is caused by a vitamin A or zinc deficiency
Deal with the deficiency
Supplement with vitamin A and zinc to correct those deficiencies
that may lead to night blindness; see your healthcare provider to determine recommended
amounts and duration of treatment
These recommendations are not comprehensive and are not intended to replace
the advice of your doctor or pharmacist. Continue reading the full night blindness article for
more in-depth, fully-referenced information on medicines, vitamins, herbs, and dietary and
lifestyle changes that may be helpful.
People with night blindness (also called impaired dark adaptation) see poorly in the
darkness but see normally when adequate amounts of light are present. The condition does not
actually involve true blindness, even at night.
Reliable
and relatively consistent scientific data showing a substantial health benefit. Contradictory, insufficient, or preliminary studies
suggesting a health benefit or minimal health benefit. For an herb, supported by traditional use but minimal
or no scientific evidence. For a supplement, little scientific support and/or minimal health
benefit.
What are the symptoms?
Symptoms include difficulty seeing when driving in the evening or at night, poor vision in
reduced light, and feeling that the eyes take longer to “adjust” to seeing in the
dark.
Other therapies
Therapy includes management of any underlying medical condition.
Vitamins that may be helpful
Night blindness may be an early sign of vitamin
A deficiency. Such a deficiency may result from diets low in animal foods (the main source
of vitamin A), such as eggs, dairy products, organ meats, and some fish. Low intake of fruits
and vegetables containing beta-carotene, which
the body converts into vitamin A, may also contribute to a vitamin A deficiency. Doctors often
recommend 10,000 to 25,000 IU of vitamin A per day to correct a deficiency. Beta-carotene is
less effective at correcting vitamin A deficiency than is vitamin A itself, because it is not
absorbed as well and is only slowly converted by the body into vitamin A.
Dietary zinc deficiency is common, and a
lack of zinc may reduce the activity of retinol dehydrogenase, an enzyme needed to help
vitamin A work in the eye. Zinc helps night blindness in people who are
zinc-deficient;1 therefore, many physicians suggest 15 to 30 mg of zinc per day to
support healthy vision. Because long-term zinc supplementation may reduce copper levels, 1 to 2 mg of copper per day (depending
on the amount of zinc used) is usually recommended for people who are supplementing with zinc
for more than a few weeks.
In a study of women in Nepal, where there is a high prevalence of iron and
riboflavin deficiencies, supplementation with 30 mg per day of iron and 6 mg per day of
riboflavin for six weeks enhanced the effectiveness of vitamin A in the treatment of night
blindness.2 It is not known whether these nutrients would be helpful for night
blindness in people who are not deficient.
Are there any side effects or interactions?
Refer to the individual supplement for information about any side effects or interactions.
Herbs that may be helpful
Bilberry, a close relative of the
blueberry, is high in flavonoids known as
anthocyanosides. Anthocyanosides speed the regeneration of rhodopsin, the purple pigment that
is used by the rods in the eye for night vision.3 Supplementation with bilberry has
been shown in early studies to improve dark adaptation in people with poor night
vision.45 However, two newer studies found no effect of bilberry on
night vision in healthy people.67 Bilberry extract standardized to
contain 25% anthocyanosides may be taken in capsule or tablet form. Doctors typically
recommend 240 to 480 mg per day.
Are there any side effects or interactions?
Refer to the individual herb for information about any side effects or interactions.
References (To view, roll mouse over the "References" heading; to hide, click on the heading)
1. Anonymous. Zinc-responsive night blindness in sickle cell anemia.
Nutr Rev 1982;40:175–7.
2. Graham JM, Haskell MJ, Pandey P, et al. Supplementation with iron and
riboflavin enhances dark adaptation response to vitamin A-fortified rice in iron-deficient,
pregnant, nightblind Nepali women. Am J Clin Nutr 2007;85:1375–84.
3. Alfieri R, Sole P. Influencedes anthocyanosides admintres parvoie
parenterale su l’adaptoelectroretinogramme du lapin. CR Soc Biol 1964;15:2338
[in French].
4. Jayle GE, Aubry M, Gavini H, et al. Study concerning the action of
anthocyanoside extracts of Vaccinium myrtillus on night vision. Ann Ocul
1965;198:556–62 [in French].
5. Belleoud L, Leluan D, Boyer YS. Study on the effects of anthocyanin
glycosides on the nocturnal vision of air controllers. Rev Med Aeronaut Spatiale
1966;18:3–7.
6. Zadok D, Levy Y, Glovinsky Y. The effect of anthocyanosides in a
multiple oral dose on night vision. Eye 1999;13:734–6.
7. Muth ER, Laurent JM, Jasper P. The effect of bilberry nutritional
supplementation on night visual acuity and contrast sensitivity. Altern Med Rev
2000;5:164–73.
The information presented in Aisle7 is for informational purposes only.
It is based on scientific studies (human, animal, or in vitro), clinical experience,
or traditional usage as cited in each article. The results reported may not necessarily occur
in all individuals. For many of the conditions discussed, treatment with prescription or over
the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist
for any health problem and before using any supplements or before making any changes in
prescribed medications. Information expires February 2010.
