This is an extract from Prof T. Colin Campbell’s book, The China Study, in the section entitled, Eye Problems
“People who can see well often take vision for granted. We treat our eyes more as little bits of technology than as living parts of the body, and are all too willing to believe that lasers are the best course of action for maintaining healthy eyes. But during the past couple of decades, research has shown that these bits of “technology” are actually greatly affected by the foods we eat. Our breakfasts, lunches and dinners have a particular effect on two common eye diseases, cataracts and macular degeneration—diseases which afflict millions of older Americans.
Yes, that’s right. I’m about to tell you that if you eat animal foods instead of plant foods, you just might go blind.
Macular degeneration is the leading cause of irreversible blindness among people over age sixty-five. Over 1.6 million Americans suffer from this disease, many of whom become blind. As the name implies, this condition involves destruction of the macula, which is the biochemical intersection in the eye—where the energy of the light coming in is transformed into a nerve signal. The macula occupies centre stage, so to speak, and it must be functional for sight to occur.
Around the macula there are fatty acids that can react with incoming light to produce a low level of highly reactive free radicals. These free radicals (see chapter four) can destroy, or degenerate, neighbouring tissue, including the macula. But fortunately for us, free radical damage can be repressed thanks to the antioxidants in vegetables and fruits.
Two studies, each involving a team of experienced researchers at prestigious institutions, provide compelling evidence that food can protect against macular degeneration. Both studies were published a decade ago. One evaluated diet and the other assessed nutrients in blood. The findings of these two studies suggested that as much as 70-88% of blindness caused by macular degeneration could be prevented if the right foods are eaten.
The study on dietary intakes compared 356 individuals fifty-five to eighty years of age who were diagnosed with advanced macular degeneration (cases) with 520 individuals with other eye diseases (controls). Five ophthalmology medical centres collaborated on the study Researchers found that a higher intake of total carotenoids was associated with a lower frequency of macular degeneration. Carotenoids are a group of antioxidants found in the coloured parts of fruits and vegetables. When carotenoid intakes were ranked, those individuals who consumed the most had 43% less disease than those who consumed the least. Not surprisingly, five out of six plant-based foods measured also were associated with lower rates of macular degeneration (broccoli, carrots, spinach or collard greens, winter squash and sweet potato). Spinach or collard greens conferred the most protection. There was 88% less disease for people who ate these greens five or more times per week when compared with people who consumed these greens less than once per month. The only food group not showing a preventive effect was the cabbage/cauliflower/brussels sprout group, which sports the least colour of the six food groups.
These two eye conditions, macular degeneration and cataracts, both occur when we fail to consume enough of the highly coloured green and leafy vegetables. In both cases, excess free radicals, increased by animal-based foods and decreased by plant-based foods, are likely to be responsible for these conditions.”
Campbell, T. Colin; Thomas M. Campbell II (2006-06-01). The China Study: The Most Comprehensive Study of Nutrition Ever Conducted And the Startling Implications for Diet, (p. 214 – 217)