Until about 200 years ago, neither salt nor sugar was readily available and therefore we ate both sparingly. We consumed sugar in the occasional piece of fruit and the odd bit of honey. Salt was similarly costly and saved for preserving food. Once we figured out how to easily manufacture salt and sugar, however, human consumption increased to levels beyond the comprehension of an 18th-century person.

It's hardly earth shattering to hear that consuming too much salt is dangerous and that sugar is not even essential to our diet. What may be surprising is to learn that campaigners against both argue they are massively underplayed health issues and that salt and sugar are actually the cause of modern health epidemics including obesity, heart disease, hypertension and even PMS.

Sweet is soured
In the anti-sugar camp is David Gillespie. A Brisbane lawyer, Gillespie lost 40kg by cutting out sugar. Intrigued, and sensing he'd stumbled across the elusive "secret" to weight loss, Gillespie applied his skills as a litigator to build a case against sugar. His book Sweet Poison: Why sugar makes us fat ($29.95, Penguin) is a 200-page prosecution of sugar — specifically fructose, the main component of cane sugar.

"Fructose, uniquely amongst the foods we eat, does not trigger an appetite response," explains Gillespie. Fat, carbohydrate and protein alert the brain when we've had enough — fructose does not. "We could eat a mountain of fructose and never feel full," He adds. For a person in the 1860s, there was no issue, as there was so little fructose to be had. In 2008, we drink sugar in juices and feast on it for breakfast, so much so that the average person is consuming 33kg of sugar a year. And it gets worse. Yes, sugar doesn't tell us when we've had our fill causing us to mindlessly consume excess calories, but it's also clogging our arteries. "Sugar is immediately converted by the liver into fat. Our bodies are extremely efficient at doing this," Gillespie says. "By the time you've finished the glass of apple juice, the first mouthful is already circulating in your arteries as fat." This fat in the arteries can lead to type 2 diabetes and heart disease.

But what of salt?
The case for sugar is not looking good but does this mean if we cut it out we can gorge on salty treats instead? No way, says Dr Trevor Beard, author of Salt Matters: The killer condiment ($24.95, Hachette). His main concerns include the 90 percent of us at risk of hypertension (high blood pressure) and the 250,000 women who suffer from severe PMS (fluid retention). He says salt consumption is the "biggest black spot in public health".

While they each have their own area of focus, both men agree this: modern processed-food-laden diets expose us to far more salt and sugar than we need. Breakfast cereals are a bugbear for both men. "About 25 percent of the average breakfast cereal is sugar," Gillespie says. Dr Beard offers this: "The food industry is guilty of doing it [adding salt and sugar to processed foods] but they are innocent in their intentions — they are simply giving us what we want. If we start wanting something better they'll give us that."

How to 'want' better food?
Just as we've evolved to love these things, we can ween ourselves to the point where they are no longer palatable. "Anthropologists have identified 20 salt-free societies," says Dr Beard. "They detest salt, yet when it's introduced they get used to it within a matter of weeks. Once they are used to salt, they start clamouring for it."

And it seems you can lose that taste as quickly as you acquire it. "Within four weeks people who give up salt don't like it anymore," he continues. For Gillespie, the key to achieving dietary balance is to focus on sugar. "Concern yourself only with the fructose content of the food and your body will take care of the rest," he says. "You will not overeat, you will not become fatter than your body is set to become."

How to limit your salt and sugar intake

• Eat as close to nature as possible. Include, in your diet, fresh vegies, some whole fruit, lean meats and whoelgrains. Processed foods are the biggest culprits for both salt and sugar.
• Don't drink sugar. This means no juices, soft drinks or cordials.
• Read the label. Salt and sugar are hidden in even the healthiest foods, including nuts, sauces and breakfast cereals.
• Prepare own food. Restaurants use more salt than you think. If you start from scratch with fresh foods you can control your intake.

For more information visit www.sweetpoison.com.au and www.saltmatters.org.