Monday, January 18, 2016
Green, Leafy Vegetables Each Day May Help Keep Glaucoma at Bay
Glaucoma is an eye condition that usually develops when fluid increases in the front part of the eye and causes pressure, damaging the optic nerve. It can lead to loss of vision, according to the U.S. National Eye Institute.
Kang’s team followed nearly 64,000 participants in the Nurses’ Health Study from 1984 through 2012, and more than 41,000 participants in the Health Professionals Follow-up Study from 1986 through 2014. The men and women were all 40 or older. None had glaucoma at the start of the study, and they had eye exams every two years.
Over the 25-year follow up, almost 1,500 people developed glaucoma. The research looked at the consumption of green leafy vegetables among the participants.
The investigators divided the participants into five groups, from the highest level of leafy green vegetable consumption to the lowest. Those who ate the most average about 1.5 servings a day, or about one and half cups a day, Kang said. Those in the group eating the least leafy greens ate about a serving every three days.
“In glaucoma, we think there is an impairment of blood flow to the optic nerve,” Kang said. “And an important factor that regulates blood flow to the eye is a substance called nitric oxide.” Green leafy vegetables contain nitrates, which are precursors to nitric oxide, the researchers said.
“When you consume the the higher amount of green leafy vegetables, you have greater levels of nitric oxide in your body,” Kang said.
Findings from the study were published online Jan. 14 in the journal JAMA Ophthalmology.
The findings make sense, said Dr. Rahul Pandit, an ophthalmologist at Houston Methodist Hospital, who reviewed the new research. This study, he said, is the first study to look at a large population and show that higher consumption of green leafy vegetables appears to decrease glaucoma risk. The findings suggest that “maybe this is something we can apply clinically,” Pandit said
I like the study although the concept that just increasing nitrates is responsible for the decrease in glaucoma is way to simplistic. There are thousands and thousands of phytochemicals common to green leafy vegetables. It is the synergistic effect of those compounds responsible for the benefit. As for the “something we can apply clinically”, how about recommending patients eat 1-2 servings of green leafy vegetables each day? Physicians monitor the pressure in the eye in glaucoma patients. If they increased their green leafy vegetable intake a corresponding decrease in eye pressure could be tracked.
The Bottom Line:
If you have glaucoma or would like to prevent glaucoma, eat 1-2 servings of green vegetables every day. I guarantee you will improve your health.
Source: January 14, 2016 National Institutes of Health