but may protect against cancer. Alcohol is okay, but only if it's wine.

The confusing studies on what is safe to eat and drink are enough to send anyone screaming to the nearest burger joint in rebellion.

But are the studies really contradictory, or does the media oversimplify and over-hype? "It is obviously a confusing world out there and certainly there is a lot of information that appears to the consumer to be contradictory,'' said Ursula Arens, a nutrition scientist with the British Nutrition Foundation. "Over time, consumers will become increasingly cynical.'' Nutritionists, too, have contradicted themselves. "An example of an absolutely dramatic major U-turn on the advice that nutritionists give is on starch,'' Arens told Reuters. Twenty years ago, slimmers were advised to stay away from potatoes, bread or pasta. "Our advice today is the complete opposite,'' she said. "Carbohydrate and particularly starch is absolute wonder stuff and really we should be eating more of it.'' The margarine-butter debate has been especially confusing. Studies that linked saturated fat -- found mostly in animal products such as meat and butter -- with cancer and heart disease sent millions rushing to buy margarine.

But then another study found that people who ate a lot of margarine also had high levels of heart disease.

Researchers blamed the hydrogenisation process that hardens oils into something more resembling butter. The trans fatty acids formed in the process acted just like harmful substances in butter, raising blood fat levels and clogging arteries. Back to the butter dish, or so it seemed.

But many doctors point out that their advice has never been conflicting. For years, and in various countries, they have recommended cutting overall fat intake.

People in such Western industrialised countries as Britain and the United States get about 40 percent of their calories from fat. Doctors say this should be around 30 or even 25 percent.

"We must try to reduce total fat, in particular saturated fat,'' said Dr.

Rudolf Riemersma of the University of Edinburgh, who has been studying the effects of fat intake for years.

"We need to go to starchy foods, more bread -- in particular brown bread -- and more fruit and vegetables.'' This means cutting down on meat, and not just to make room for the extra vegetables and grains.

Dr. Alan Boobis of the Royal Postgraduate Medical School in London says various studies have shown a link between eating red meat and bowel cancer.

"During the cooking process, the action of heat on natural components of the meat results in the formation of a group of compounds known as HAs (heterocyclic amines) which can cause cell mutation,'' Boobis said.

There was also the "mad cow disease'' scare in Britain, when tens of thousands of cattle developed Bovine Spongiform Encephalopathy, which destroyed their brains.

Although there is no firm evidence that people can get it from eating beef products, the human version, Creutzfeld-Jakob disease, has a long incubation period and new rules on butchering cattle were instituted to reduce risk of infection.

So if you can't eat meat, should you eat fish? Fish oil has been linked with reduced risks of disease -- specifically its content of omega-three fatty acids, which seem to reduce cholesterol build-up.

But a survey of 45,000 men found that those who ate five or six servings of fish a week had just as much heart disease as those who ate two or three portions.

And environmentalists say fish taken from heavily polluted waters like the North Sea or the Great Lakes could carry enough poisonous heavy metals in their flesh to be dangerous.

Fresh produce, moreover, may not be so safe either. Last month the British government advised consumers to peel their carrots because of pesticide contamination, while many Americans briefly boycotted apples because of fears over the chemical alar.

But Arens said any risk of pesticide poisoning would be outweighed by the costs of not eating plant foods.

"In balance, if you were to put both risks against each other, the advice has to be eat as much fruit and vegetables daily as possible.'' What about coffee and tea? Doctors recommend cutting caffeine, but some studies have shown that even heavy coffee drinkers have a reduced risk of cancer of the colon.

Only a very few studies have linked coffee with heart disease, and most were done in Scandinavia among limited populations and using boiled coffee -- now rarely drunk in many parts of the world.

In general, nutritionists conlude, variety truly is the spice of life. "The general advice is pretty much the same advice that nutritionists have been rabbiting on about for donkey's years -- a varied diet, a mixture of foods and not too much of any one,'' Arens said.