Omega-3s May Help Prevent Blindness
Early Tests in Mice Show Omega-3 Fatty Acids May Curb Unhealthy Blood Vessel Growth in Eye
WebMD News Archive
June 25, 2007 -- Omega-3 fatty acids may help prevent blindness by thwarting
the growth of abnormal blood vessels in the eye.
That news appears in the advance online edition of the journal Nature
Three leading causes of blindness are age-related macular degeneration,
diabetic retinopathy, and retinopathy related to premature birth.
All three conditions involve retinopathy, which is the abnormal development
of blood vessels in the eye.
Omega-3s may reduce retinopathy, according to the new study, which involved
tests on mice.
If the findings apply to people, "simple supplementation [with omega-3
fatty acids] could be a cost-effective intervention benefiting millions of
people," says Lois Smith, MD, PhD, in a news release from Children's
Smith works in the ophthalmology department of Harvard Medical School and
Children's Hospital Boston.
Omega-3 and Omega-6 Fatty Acids
Smith and colleagues studied omega-3 and omega-6 fatty acids in newborn
The body needs omega-3s and omega-6s and must get those fatty acids through
diet or supplements.
Western diets tend to be heavy on omega-6s and skimpy on omega-3s.
Omega-6s are found in meat and vegetable oils such as safflower oil,
sunflower oil, corn oil, and soy oils. Food sources of omega-3s include leafy
green vegetables, walnuts, flaxseeds, and fatty fish such as salmon, herring,
Smith's team added omega-3s or omega-6s to the diets of female mice that had
just given birth. The mother mice passed the omega-3s or omega-6s to their
newborns through their breast milk.
The omega-3 supplements were given at a dose similar to that of the
traditional Japanese diet. The omega-6 supplements were given at a dose like
that of a typical Western diet.
The baby mice were exposed to high levels of oxygen for five days, starting
when they were 1 week old.
Those conditions put the eye at risk of losing healthy blood vessels, which
sets the stage for abnormal blood vessels to develop.
The newborn mice kept more of the healthy blood vessels in their eyes if
their mothers' diets were supplemented with omega-3s instead of omega-6s.
With more of their healthy blood vessels intact, the newborn mice in the
omega-3 group were less likely to have abnormal blood vessels develop in their
In short, omega-3s reduced retinopathy before it started. The study shows
that the results may be related to omega-3s' anti-inflammatory effects.