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Can a junk food diet cause someone to go blind? Researchers at the University of Bristol in England say that's what seems to have happened to one teenager. They published a case study in the medical journal Annals of Internal Medicine. NPR's Allison Aubrey reports.
ALLISON AUBREY, BYLINE: Several years back, a 14-year-old boy went to the doctor complaining that he was tired. At the time, doctors said he appeared healthy. He was not overweight and took no medications, but his diet was bad - really bad. According to the report, he ate mostly white bread, chips and bits of processed meat.
ALLEN TAYLOR: The fact is that the boy was eating so much junk food.
AUBREY: That's researcher Allen Taylor of Tufts University. He was not involved in the case study, but he agreed to review the findings for us. He says it is very unusual for a teen to develop the condition that this teen did. It's called optic neuropathy.
TAYLOR: Optic neuropathy is an inflammation of the optic nerve that carries information from your eyes to your brain.
AUBREY: Usually, it's a temporary condition, but in the reported case study, the teenager's vision loss was permanent, so Taylor says he'd like to know more.
TAYLOR: Actually, the diagnosis is quite puzzling to me.
AUBREY: Perhaps there were other issues with this teenager, but Taylor says the case is an opportunity to point out to people that poor diet can lead to vision problems.
TAYLOR: Consuming a diet rich in such poor-quality carbohydrates can, in fact, compromise vision.
AUBREY: Now, this usually does not happen during the teenage years. It's much more common later in life. Taylor and his collaborators studied about 20,000 people to see how their diets influenced the risk of age-related macular degeneration, which tends to occur after age 60.
TAYLOR: We found that, the more you eat the junk food diet, the greater your risk for macular degeneration is, and the more you eat the healthy diet, the less you have a risk for macular degeneration.
AUBREY: At a time when there are conflicting ideas about what makes a healthy diet, Taylor explains, in the study, people who eat plenty of fruits and vegetables, whole grains, tomatoes and seafood had a lower risk, but people who consumed a lot of red and processed meat, fried food and refined carbohydrates had a higher risk. So Taylor's advice...
TAYLOR: Be sure that you feed yourself and your loved ones a diet that's rich in fruits and vegetables.
AUBREY: And dial back on the white bread and those chips.
Allison Aubrey, NPR News.