FROM:
J Am Optom Assoc 1999 (Jan); 70 (1): 39–47
Pratt S
BACKGROUND: Age-related macular degeneration (ARMD) is
the leading cause of blindness in people over the age of 65, and
the prevalence of ARMD is expected to increase as the population
ages. Although the incidence of ARMD increases sharply with age,
recent studies indicate that prevention measures and dietary
changes, implemented early in life, can reduce an individual's
risk of ARMD.
METHODS: Several dietary components have been proposed
and studied with regard to their ability to protect against ARMD;
these components include antioxidant vitamins and specific
carotenoids. In particular, consumption of dark green, leafy
vegetables has been shown in clinical studies to reduce the risk
of ARMD.
RESULTS: Biochemical studies of such vegetables have
found that they contain several nutrients that may account for
this effect, including high concentrations of the related
carotenoids lutein and zeaxanthin. Structural and clinical
studies have shown that these carotenoids are concentrated in the
retinal macular pigment and that such accumulation is dependent
on dietary intake. Further studies have indicated that the
density of the macular pigment is related to preservation of
visual sensitivity and (possibly) protection from
ARMD.
CONCLUSIONS: Large-scale clinical trials will be
necessary to demonstrate that specific agents can reduce the
incidence of ARMD. Nevertheless, specific dietary components--
particularly, the carotenoids found in dark green, leafy
vegetables--have shown great promise. While lifestyle
modifications such as smoking cessation, reduction of alcohol
consumption, and the wearing of sunglasses may reduce the risk of
ARMD, it is likely that consumption of specific dietary
components can reduce the risk further.