Paul Thomas: Beware fishy claims of white coat brigade

One of the defining features of contemporary life is the never-ending search for things that taste good and also happen to be good for us or, failing that, don't take years off our lives or sap our vital bodily fluids.

Salmon was one of the few things that fell into this category. It was so good for us, according to the medical establishment, that we couldn't have enough of it.

Possessing the twin virtues of being expensive and resoundingly PC, the slab of (often slightly undercooked) salmon became the trendy middle-class dinner party dish of choice.

Those who expressed a primitive yearning for hearty red meat stews or a good old-fashioned roast risked being sent outside to join the smokers and anti-anti-Americans.

However, Britain's Independent newspaper reports that scientists who reviewed 89 studies of omega 3 fats, the constituent in oily fish such as salmon that supposedly confers a panoply of health benefits, have concluded there's not a skerrick of evidence to support the propaganda we've been bombarded with for the past 20 years.

If propaganda seems too strong a word, consider the claims that have been made on behalf of oily fish:

* It prevents cancer and heart disease.

* Eating it once or twice a week reduces the risk of strokes and averts premature births.

* It cures asthma and inflamed bowels, prevents skin cancer, halves the risk of prostate cancer, keeps wrinkles at bay, minimises the prospects of getting Alzheimer's disease and soothes psoriasis.

The good that oily fish did was so diverse and far-reaching one had to wonder whether it should be classified as a mere food; it was more like nature's wonder drug.

In 2003 researchers in Mauritius concluded that children who eat lots of oily fish were 64 per cent less likely to have a criminal record by the time they reached 23. In other words, if salmon farmers really got their arses into gear, it would be safe to walk the streets at night and we'd be spared this apparent plague of lawyers.

The high priest of the salmon cult was Professor Michael Crawford of the Queen Elizabeth Hospital in London, who warned that mothers who didn't eat oily fish were hindering their unborn babies' brain and eye development.

Parents used to tell their little ones they'd get a visit from the boogie man if they didn't eat their greens. Being an eminent scientist, Professor Crawford wouldn't stoop to such mumbo-jumbo; instead he pointed out that if we didn't eat enough oily fish we'd send evolution into reverse.

Apparently the only reason homo sapiens is master of all he surveys, while monkeys sit around in trees all day worrying about deforestation, is that our ancestors lived on oily fish, thereby developing big brains, while the other primates stuck to bananas, which are good for blood pressure and bowel movements but don't do much for the grey matter.

Any commercial organisation making these sorts of claims on behalf of its products in a marketing campaign would be hauled before the Advertising Standards Authority. But whenever a group of researchers reports some half-baked finding on the health implications of what we eat and drink, it flashes around the world with all the authority and finality of a sports result or the Dow-Jones close.

These scientific surveys are our enlightened age's equivalent of old wives' tales. Undue respect for the wisdom of elders has been replaced by undue respect for men and women in white coats with a few letters after their names.

Generations of children grew up believing:

* Feed a cold, starve a fever.

* Coffee stunts your growth.

* After a meal you should wait an hour before swimming to avoid the risk of cramps.

* Chocolate causes acne.

* Spicy foods cause ulcers.

* Reading in dim light damages your eyesight.

* If you go outside with wet hair you'll catch a cold.

* Eating carrots enhances eyesight.

No doubt many people still believe some of the above but they're all old wives' tales or their modern equivalent, urban legends.

(According to something I stumbled across on the internet, the carrots/eyesight connection was dreamed up by British Intelligence during World War II in an attempt to conceal the role that radar was playing in the air war: RAF pilots had good night vision because they ate lots of carrots. As with so much that supposedly emanates from the intelligence community, it's indistinguishable from absurdist comedy.)

The difference between old wives' tales and scientific surveys is that the former tended to be underpinned by personal experience; the error lay in extrapolation.

I'd always thought there was something in the wet hair business because I came down with a shocking cold after walking home from the gym one cold European night without bothering to dry my hair.

And I firmly believe a spoonful of vinegar stops the hiccups. It's always worked for me and it worked for our 12-year-old the other night.