For decades, we were told that margarine was the healthy alternative to butter. That was during the era of fat is bad but sugar is sweet.

Then Harvard University conducted a study showing that women who ate four teaspoons of margarine a day had a 50 per cent greater risk of heart disease than those who didn't eat margarine

Now wheat and gluten, the chewy, elastic protein it contains, are enduring a similar treatment.

Wheat is a staple part of our diet and Australia's largest and most valuable crop. Yet, people are abandoning damper and the like in droves.

Recent studies and books say carbs and sugar are bad, but fat is fine.

They argue that wheat is not just poisonous to those with coeliac disease - which is about 2 per cent of the population.

"Cutting-edge research, for example, has revealed that consumption of modern wheat is the first step in triggering autoimmune diseases such as type 1 diabetes, rheumatoid arthritis, and multiple sclerosis," argues Dr William Davis, cardiologist and author of Wheat Belly.

Gluten sensitivity "represents one of the greatest and most under-recognised health threats to humanity," says neurologist David Perlmutter, author of Grain Brain: The Surprising Truth About Wheat, Carbs, and Sugar - Your Brain's Silent Killers.

So everyone from life coaches,  podiatrists, chiropractors, even psychiatrists (citing links between gluten and depression) are prescribing a gluten-free diet.

This is despite many gluten-free versions of traditional wheat-based foods being doubly expensive and actual junk foods.

So should we all banish bread and other delightful gluten-containing foods from our diets?

In the extensive New Yorker feature, science and health writer Michael Specter, who happens to love baking bread, explores the chewy debate about gluten.

He poses the question: "How could gluten, present in a staple food that has sustained humanity for thousands of years, have suddenly become so threatening?"

One argument is that the bread of today is a different beast to the one of yesteryear.

"The version of 'wheat' we consume today is a product of genetic research," Dr Davis says.

"You and I cannot, to any degree, obtain the forms of wheat that were grown 50 years ago, let alone 100, 1000 or 10,000 years ago. We have to restrict other carbohydrates beyond wheat, but wheat still stands apart as the worst of the worst."

Perlmutter, he writes, is less restrained: "As many as 40 per cent of us can't properly process gluten, and the remaining 60 per cent could be in harm's way."

Some say that this generation is reaping the health repurcussions of what our recent ancestors' dietary choices have sowed.

Another argument is that the amount of gluten added to industrially made bread keeps increasing.

Traditionally, bread-making involves leaving the dough to sit as the water slowly absorbs into the flour, fermenting it and allowing the yeast and bacteria to activate the dough.

Kneading the dough then combines the proteins created through fermentation, to form gluten. Extra gluten is often also added to create the rise and chewy texture we so love in bread.

Industrial, mass-produced breads, however, tend to speed up the process and bypass fermentation by using additives and then mechanically mixing the dough to create gluten.

The mechanisation of bread also allows manufacturers to easily discard the nutrient and fibre-dense parts of the wheat kernel - the germ and the bran - to create white flour.

Now, while coeliac is recognised, gluten-sensitivity or intolerance are still being debated.

Most recently there was an Australian study that found only 8 per cent of participants with self-diagnosed gluten-sensitivity suffered a gluten-specific problem.

In fact, in the subjects' reports of worsening symptoms, even while on the placebo diet, could be explained by a nocebo effect, where we feel worse when we expect to feel worse.

The researchers concluded that, the more likely cause of the symptoms such as bloating and gut distress was short-chain carbohydrates called FODMAPs (fermentable oligo-saccharides, disaccharides, mono-saccharides and polyols).

When the gluten-free brigade became upset at the suggestion that gluten-sensitivity doesn't exist, lead researcher Peter Gibson, of Melbourne's Monash University, defended the results.

"There are some people who have claimed that we're anti-gluten or we're this or that. We're not. We're trying to find out what the reality is because we know that a lot of people go on gluten-free diets, feel better. And that's not imagination, that's real," Gibson has said.

Trying to find out might take a while, says Nathan Myhrvold author of the forthcoming The Art and Science of Bread.

"To find out the effect something like gluten has on people's diets is complicated," he told Specter. "We'll need long-term studies, and there won't be a useful answer for years.

"So, instead of telling everyone you are going on a gluten-free diet, what if you said, 'Hey, I am going on an experimental regimen, and it will be years before we know what effect it might have'. I don't know about you, but instead of saying 'eat this because it will be good for you,' I would say, 'good luck'."

For Specter's part, he is willing to try his luck. But will still ditch the commercially made breads as well as the added gluten that had become the "magic wand" for making his own home-made bread rise.

"I have returned to baking whole-wheat bread the way it is supposed to be made: water, yeast, flour, and salt," he says. "I will try to live without the magic wand.

"But I am certainly not going to live without gluten. That just seems silly."