Should we take That Sugar Film with a grain of salt?

That Sugar Film's dramatic depiction of how taking things to the extreme can be harmful might well have entertainment value, but it has a Deakin University health scientist asking if it is casting sugar in the right light.

"There is no doubt that sugar is today's number one dietary demon," said Deakin's Associate Professor Tim Crowe. "While nutrition scientists debate the harms or otherwise of saturated fat, sugar is the one food we unite over – we all agree we eat too much of it and it's not good for us

"The film's release is timely given the World Health Organization's recent draft recommendations to eat no more than 12 teaspoons (50 grams) per day, and to aim for even half of that amount. And while it does well to shine a light on just how damaging sugar can be and how it has pervaded our food supply, some of the details are questionable."

Associate Professor Crowe points to a number of aspects of the film that skew the true sugar story.

IN THE FILM: Actor Damon Gameau consumes the equivalent of 40 teaspoons (around 160 grams) of sugar a day for 60 days by eating foods perceived as being healthy such as fruit juice, sports drinks, low-fat yoghurts, muesli bars and sugary breakfast cereals.

FACT: It is true that the average Australian between the ages of 19 and 30 years eats 40 teaspoons of sugar a day but this accounts for all forms of sugar, including what is found naturally in fruit, fruit products and milk. Using 40 teaspoons of white sugar paints a sensational picture but it is not entirely true. The actual amount of added sugar we eat is more like 66 grams or about 16 teaspoons a day for the average adult.

IN THE FILM: Gameau claims his weight gain happened despite eating the same amount of food before the experiment.

FACT: Only a superficial attempt was made to estimate how much food was eaten during the experiment, making such claims about weight gain unreliable. There is nothing insidious about sugar calories that can lead to greater weight gain. Its effect on weight is from extra energy it adds to our diets, that's all. What can make sugar fattening is the context it's normally eaten in. It increases the calorie density of food and makes it more palatable and desirable which in turn means people are more likely to eat more than is good for them.

IN THE FILM: Whether sugar is inherently addictive is questioned

FACT: If you're a rat, then sugar would most certainly be your drug of choice. In humans, however, the science is at best hazy. The thing to remember is that eating is addictive – just try going a day without food.

After the short-term sugar-shock from watching the film wears off, Associate Professor Crowe says there are a few simple changes people can make to eat less sugar and improve their overall diet.

"My tip is to start looking more closely at food labels and ingredient lists. The more processed and convenient a food is, the more likely it will have extra sugar in it," he said.

"Simpler yet, ditch the label reading altogether and choose foods as close to their natural state as possible. Many of these foods don't need a label and have a very short ingredient list."

That Sugar Film is screening in Australian cinemas this month.