A study of more than 1,800 women has found that those who scored among the highest group for following nationally recommended dietary guidelines had a 37% lower risk for nuclear cataracts, the most common cause of visual impairment in the United States. This association held even after adjusting for other non-dietary-related factors.
The healthy diet linked to this reduced risk featured high quantities of fruits, vegetables, whole grains, and lean protein such as beans, fish, eggs, and low quantities of salt and fat.
Overall, a higher prevalence of cataracts was associated with poor diet and other lifestyle factors, including smoking and obesity. Having brown eyes, being nearsighted, and having a high pulse pressure were also associated with increased prevalence for cataracts. Interestingly, taking multivitamin supplements did not appear to affect cataract risk. The findings are reported in the June issue of Archives of Ophthalmology.
Cataracts Common in Americans
The results are based on 1,808 women ages 50 to 79 who participated in the Carotenoids in Age-Related Eye Disease study. The women filled out questionnaires about their diets between 1994 and 1998. The researchers determined prevalence of nuclear cataracts from photographs and self-reports assessed between 2001 and 2004. Whether the findings could apply to men was not addressed in this study.
The risk of cataracts rises with age. Researchers said their findings suggest that some risk factors , including diet, may be within the individual’s control.
Cataracts are so common that treating them has created a heavy economic toll. Reducing the risk for cataracts could ultimately produce cost savings. “Surgery to remove lenses with cataracts accounts for approximately 60% of vision-related Medicare expenditures,” write study researcher Julie A. Mares, PhD, of University of Wisconsin in Madison, and colleagues.
According to the American Academy of Ophthalmology, more than 20 million Americans 40 and older have cataracts. Half of all Americans have cataracts by age 80.
“Results from this study indicate that healthy diets, which reflect adherence to the U.S. dietary guidelines at the time of entry in the ... study, are more strongly related to the lower occurrence of nuclear cataracts than any other modifiable risk factor or protective factor studied in this sample of women,” the researchers write. “Lifestyle improvements that include healthy diets, smoking cessation, and avoiding obesity may substantively lower the need for and economic burden of cataract surgery in aging American women."
The research team notes that cataract risk was not “driven by any single dimension of diet.” They also point out that women who ate healthier food were also women who had more education, were older, and engaged in other healthy lifestyle habits, including maintaining a low body weight, being more physically active, and being less likely to smoke.