By Syed AkbarTurmeric, a common kitchen ingredient, has been known
for its anti-septic properties, and city nutritionists now find out that
it also has the natural chemicals that are capable of preventing cataract in people
suffering from diabetes.
"It is for the first time we report that turmeric, at the levels that are
close to average daily intake, can be effective in preventing diabetic cataract.
One of the important observations of this study is that both turmeric and its
chemical constituent, curcumin, delay the progression and maturation of cataract,
despite elevated levels of glucose. These results thus provide a clue, for
the first time, that turmeric or curcumin may act downstream to glucose-
mediated changes," says a study by nutrition scientists of the National
Institute of Nutrition.
Diabetes and cataract are inter-linked and cataract is more pronounced in
people suffering from the disease. At present, the only treatment for
cataract is surgery.
It has been estimated that a delay in cataract onset by 10 years
could reduce the need for cataract surgery by as much as half. The
pronounced effect of turmeric may be due to other ingredients besides curcumin
The NIN study gains significance as any strategy that prevents or
slows the progression of cataract has a significant health impact.
The joint study by P Suryanarayana, M Saraswat, T Mrudula and others
involved feeding Wistar rats a diet including curcumin and turmeric. The
turmeric and curcumin rich diet delayed the progression of diabetic cataract
in rats. "Although, multiple mechanisms may contribute to these effects, the
antioxidant effect of curcumin and turmeric appears to be the predominant
mechanism of action," they said.
The NIN scientists selected Wistar rats and diabetes was induced by
streptozotocin (a substances that damages insulin producing cells). They
monitored the cataract progression due to hyperglycemia (high levels of
sugar in blood). At the end of eight weeks, the animals were killed and the
crystalline profile in the lens was investigated.
"Although, both curcumin and turmeric did not prevent streptozotocin-
induced hyperglycemia, as assessed by blood glucose and insulin levels, slit
lamp microscope observations indicated that these supplements delayed the
progression and maturation of cataract," they added.
The results indicated that turmeric and curcumin are effective against the
development of diabetic cataract in rats. Further, these results imply that
ingredients in the studys dietary sources, such as turmeric, may be explored
for anticataractogenic (that works against cataract formation) agents that
prevent or delay the development of cataract.