Herb's elusive benefits
Oct. 16, 2000 -- Night after night during World War II, the bomber crews of Britain's Royal Air Force (RAF) climbed into their planes for perilous missions over Germany. The pilots had trouble seeing in the darkness, though, until one man's elderly relative whipped up a batch of bilberry jam. Once the heroic lads began tucking into the preserves before missions, they hit their targets with devastating accuracy.
Or so goes the story, repeated on countless web sites that offer bilberry supplements for sale. "RAF pilots who survived and continued consuming the jam or other Bilberry products had . . . perfect vision both near and far as well as a complete absence of eye disorders throughout their lives," writes Robert Biddleman on Herb.com.
Largely on the strength of that tale, bilberry -- a European cousin of the blueberry -- has become one of the 10 most popular herbs in the United States. According to The Hartman Group, a market research firm, bilbery's sales soared to $97 million in 1999, tripling in just two years.
Fascinated, WebMD set out to learn more. What we found, however, gave us little reason to increase our bilberry intake. Rather it tended to illustrate the power of a heartwarming tall tale over the cold facts of scientific research.
The Berry Hunt
We began our inquiry by trying to contact Biddleman, a Sonoma County, Calif., herbalist. Unfortunately, he was away on an herb picking expedition in Nepal. His colleague at Herb.com, Rebecca Starm, MD, maintained that he had contacted the pilots who continued to use bilberry after the war and had confirmed their extraordinary medical histories with their doctors and families. But she could offer no documentation.
Next we approached Thomas Dobie, MD, PhD. In addition to flying a Wellington bomber during World War II, Dobie now directs the National Biodynamics Laboratory at the University of New Orleans. With his combination of medical expertise and personal experience, Dobie seemed in a perfect position to confirm the tale. But while he snacked on wild bilberries as a child in Scotland, Dobie had no recollection of slathering bilberry jam on his wartime toast.
Perhaps the bilberries were served in a different mess hall, or after Dobie's tour of duty. So we asked Col. Mark Well, PhD, head of the history department at the U.S. Air Force Academy and author of a 1995 book on the experiences of World War II airmen, what he knew about the RAF's secret weapon. "In all my work on the RAF Bomber Command, I've never run across any reference to bilberry whatsoever," he said.
Puzzled, we turned to British experts at the RAF Museum, the Imperial War Museum, the RAF Centre of Aviation Medicine and the Bomber Command Historical Society. None could find so much as a smudge of jam in their files.
Of course, it's impossible to prove that no RAF pilot ate a bilberry during the Second World War. What really matters is whether the berries provide the benefits that advocates claim. According to the web site of the Vitamin Planet supplement stores, bilberry helps "control insulin levels and strengthen connective tissue," has "positive benefits toward hypoglycemia, inflammation, stress, anxiety, night blindness, and cataracts," and "may help halt or prevent macular degeneration."
Does It Work?
Few of these claims have been studied. But, inspired perhaps by the RAF legend, a handful of researchers have looked into the vision boosting effects of the berries. Three French studies from the mid-1960s found improved light sensitivity in pilots, air traffic controllers, and truck drivers who had taken bilberry. A 1987 Italian report on 34 patients suggested that bilberry might fortify leaky blood vessels in the retina. On the other side of the balance, a 1997 Israeli study on 18 people found no effect of bilberries on night vision.
The only rigorous trial carried out in the United States also reached a dim conclusion. With an eye to sharpening the night vision of U.S. Navy Seals, scientists at the Naval Aerospace Medical Research Laboratory in Pensacola, Fla., gave 15 subjects bilberry capsules and tested their visual acuity and contrast sensitivity in a darkened room.
In the April 2000 issue of Alternative Medicine Review, the researchers reported that they found no improvement in either measure, although the subjects swallowed the maximum recommended dose of bilberry for three weeks (some web sites promise results in as little as 20 minutes). Since the study was small and included only healthy men, it doesn't rule out possible benefits from bilberry, says Lt. Eric Muth, PhD, a member of the research team. But the results convinced the Navy to forget the herb as an aid for night combat. Says Muth, "If you asked me, 'Should we put our special forces on this to improve their night vision?' I'd say, 'Don't waste the taxpayers' money.' "
From this slim scientific record, you can't draw firm conclusions about whether bilberry works, say American researchers. "It's potentially an interesting area," says Frederick Ferris, MD, head of clinical trials at the National Eye Institute, "but I have no idea whether this is helpful or harmful." Commission E, a panel of experts convened by the German government to assess the safety and effectiveness of herbs, reached a similar verdict. Their monograph approves bilberry for only two conditions: diarrhea and inflammation of the mouth or throat.
But that won't convince a lot of supplement buyers, says Anthony Pratkanis, PhD, who researches marketing psychology at the University of California-Santa Cruz. Results from the sterile labs of scientists matter less to many people than the flavor of home-cooked medicine. The RAF tale presents a scenario in which "traditions win out over science. You've got these pilots stuck with a dangerous mission, and in rushes Grandma with bilberry jam."
So where did the story start? We may never know for sure, but David Holmes of Raleigh, N.C., suggests an intriguing possibility. He remembers hearing from his grandfather, who flew with the RAF during World War II, that the bombers' accuracy did suddenly improve after Britain began using radar. In order to hide the invention from the enemy, the Allies said the improvement resulted from something added to the pilots' diet.
"But," says Holmes, "in the story I heard, it was carrots."
Mitchell Leslie writes about science and health for New Scientist, Science, and Modern Drug Discovery.
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