Australia’s tank commanders are having trouble telling which large objects on the parade ground are tanks and which are the men who are supposed to be driving them. Things in the navy are a little easier. The ships are the grey things.

Recent reports have revealed that one in seven military folk is medically obese. A number like that would be trumpeted from the highest government office if it applied to the rest of us. The non-military portion of society sailed past those figures sometime in the 80s. But it’s troubling to those who were counting on the military to be of some use should we be attacked.

The average Australian digger is now 16 kilograms heavier than the men who stormed Gallipoli. But those men came from very different time and ate a very different diet. In 1915 Cadbury had only just started shipping its Dairy Maid Chocolate bar, the first ever packaged chocolate product. In the United States, Coca-Cola and Pepsi-Cola were still garage operations run out of sheds behind the pharmacies of their inventors. The men stepping ashore at Anzac Cove had never even tasted packaged chocolate or fizzy drink unless they had a generous relative in the mother country.

Corn flakes were the stuff of science fiction. Men shipping out for Gallipoli wouldn’t be able to buy breakfast cereal for another decade. And the only place they’d taste fruit juice they hadn’t squeezed themselves was in Church on Communion Sunday. It would be 40 years before they could buy orange juice at all in Australia.

There weren’t many overweight people. Four out of every five people from that time were downright skinny by today’s standards. Obesity was as rare then as underweight politicians are today. There was no such thing as heart disease and the medical speciality of cardiology wasn’t even going to be necessary for another quarter of a century.

Obviously no-one was getting rich selling diets or gym memberships. There wasn’t even enough interest in diets to start a woman’s magazine. The first copy of Women’s Weekly wouldn’t be rolling off the presses for another quarter of a century and it would be more than half a century before the first Weight Watchers meeting would happen.

The men who went off to fight at Gallipoli had grown up in households where sugar was a very occasional treat. It was too expensive to use every day and almost none of their food had any added before they bought it.

That’s a stark contrast to today where the modern soldier is fed sugar in almost every mouthful. They are eating almost 1.4 kilograms of sugar a week. Sugar is embedded in everything from their breakfast cereal to their drinks and everything in between.

The tidal wave of sugar is causing the epidemic of obesity and its nasty consequences from heart disease to diabetes. Unfortunately what we are seeing is just the start of what will turn out to be a significant problem for the defence forces (and everyone else) in the coming decade.

The military is tough on who it is prepared to take. Before 2006 you couldn’t have a Body Mass Index (BMI) of more than 30 (the border between being merely overweight and being obese). In 2006, as part of the Government’s drive to increase recruitment, the goal post was moved to 33. Not surprisingly, the military is conducting a study to see if the goal post can be moved again.

The elephant in the room (or perhaps in this case, on the parade ground) is getting hard to hide. For decades there has been grumbling by researchers who couldn’t prove that feeding rats fat made them fat, but could prove that feeding them sugar not only made them fat but gave them heart disease, type II diabetes, fatty liver disease and testicular atrophy.

There is now no scientific doubt that dietary sugar is directly responsible for raising the amount of circulating fat in our body. And the evidence is becoming overwhelming that it is the fructose half of sugar which measurably and directly produces obesity. But simply telling an obese soldier (or anyone else) to stop eating sugar is pointless in a society where it is almost impossible to find a food that does not have sugar added.

The well-meaning digger may no longer put a teaspoon of sugar in their cuppa, but what about the fourteen teaspoons in their ‘healthy’ breakfast cereal and small glass of ‘unsweetened’ apple juice? Or the teaspoon of sugar in every dollop of sauce or mayonnaise?

Obesity can be eliminated as a chronic health problem by the simple removal of fructose from the Australian diet. If that were the rule tomorrow, the industrial food complex would have fructose free foods (which tasted identical) on our supermarket shelves by next Tuesday. But until that is the rule, we will all pay the price with increasingly impaired lifestyles and ultimately shortened lives.

David Gillespie is a lawyer and author of Sweet Poison: Why Sugar Makes Us Fat (Penguin).