A steady diet of food myths

The rumour mill in the kitchen is perennially alive and well. Some old wives' tales seem just as likely to be disproven as they are to be proven, while other traditional panaceas, such as antioxidant-rich chicken soup to help heal the flu-weakened body, have more validity to them. I was a paranoid child. While other children fretted over ghost stories, I had nightmares about an eccentric family friend who once told me over ice cream sundaes that the ubiquitous, red-dyed maraschino cherries crowning my banana split would stain the lining of my stomach and glow, lurid and electric, until long after I was dead and buried. Thanks to Snopes.com, a mostly reliable encyclopaedic reference guide to urban legends, sceptics and bored recipients of e-mail forwards in the spirit of the legendary Kidney Heist, the thousand-dollar chocolate chip cookie recipe, or the deadly soda can lids laced with Leptispirosis-spiked rat urine now have a source for credibility checks - and possible rebuttal.

When I was in the fourth grade, a classmate told me that swallowing a watermelon seed could lead to melons swelling forth from the depths of my gut. I sat paralysed for the remainder of class, my mind held captive by the terror of the image of a dark subterranean tree bearing infant-sized fruit, its root systems coiled around my intestines and squeezing tight. Fortunately, I did not lose much sleep over this concern, as my mother favoured kiwis over melon, having heard through the proverbial grapevine that kiwis are highest in vitamin C and fibre of any readily available fruit. My siblings and I were stubborn about our daily kiwi, but Mum was lovingly ruthless and uncompromising. She'd peel and slice one for each of us, or for variation, scoop the flesh from each half with a spoon, discarding the fruit's hairy skin. Ten thousand kiwis later, when I could no longer bear to look at the things, I discovered that though they are high in vitamin C and fibre, both nutrients are contained in the skin, which we always threw away.

The term "urban legend", as used by folklorists, was introduced circa 1968 by the University of Utah English professor Jan Harold Brunvand. Brunvand's choice of phrase affirms that folklore is not limited to primitive or traditional societies, and that the legends and myths being propagated in a modern urban culture can provide valuable insight into its inner workings. Countless food myths are being propagated around the world. Some are based on factoids, some are based on regional oral folklore, and others are simply the result of ignorance. But every now and then, myths result from people looking at, and subsequently finding, patterns in nature. I once received an e-mail forward, which contained an extensive list of foods thought to resemble body organs along with a list of their respective functions as they related to those organs. Many of these entries were a stretch: I wouldn't think to compare bok choy to bones, or a sweet potato to a pancreas. In classic fashion, my response to the e-mail was rife with sarcasm: "Mussels resemble alien foetuses and are awesome for channelling extraterrestrial life!" I quipped, annoyed. "Next week's lesson: The inimitable tendency humans have to look for reasons and ascribe significance where there is none. Stay tuned."

Years later, in Chinese medicine school, I was the sceptic who often rolled my eyes when we were taught that certain foods mirrored the body parts they benefited; for instance, walnuts look like little brains and are rich in omega-3 fatty acids, which are necessary for proper brain function. And though I'm by no means a reformed sceptic, these days I find myself amused by this idea in a way I previously was not.

"Eat soy, we were told. It lowers your cholesterol. Don't eat soy, it affects thyroid function. Drink milk, you need the calcium. Don't drink milk, it forms mucus. Drink coffee, it is full of antioxidants. Don't drink coffee, it raises blood pressure," writes the chemist Joe Schwarcz in the introduction to his recently published, An Apple a Day: Myths, Misconceptions and Truths about the Foods we Eat.

In the book, Schwarcz examines and investigates scores of widely held notions about food, but by far the most illuminating to me was the chapter on sugar, in which Schwarcz examines the perceived connection between sugary foods and hyperactivity in children. "Desperately searching to find a reason for bad behaviour, parents began to see links between eating sugar and hyperactivity. But wait a minute. Could it not be that children eat more sugary foods during activities that are conducive to adverse behaviour, such as birthday parties? And that sugar does not cause the problem?" He goes on to cite several studies that support his claim that sugar does, in fact, have a calming effect on children by elevating serotonin levels. Though Schwarcz does not advocate feeding children sugary processed foods, his point is that sugar is not always the culprit. "So give your kids apples and carrot sticks instead of cakes and ice cream at the next party, but if you want good behaviour, hire a cellist instead of a clown."

As for a guarded myth of dieters everywhere, does one expend more calories consuming a stick of celery than are contained in the celery itself? The jury is out. But one thing is for sure: if it sounds too good to be true, then it is. And a diet of celery, whether calorie-free or not, is hardly a sustainable one. The reason that the notion of cold water boiling faster than hot water sounds silly is because it's not true. That said, starting with cold water is often advised because its route to the sink tends to be a cleaner one than that of hot water. Indeed, some food myths cultivate good habits, and are composed of sound advice based on faulty logic. Drinking copious amounts of cola won't burn a hole through your gut any sooner than swallowing gum will give you appendicitis, though that doesn't mean that you should do either on a regular basis.