Just what does a high-sugar diet do to your body?

Most of us are tuned in to the dangers of sugar.

And it’s no surprise that most low-fat health foods like yoghurts, cereals and breakfast drinks contain an unhealthy amount of sugar. But what exactly does it do to your body? That’s what Australian actor Damon Gameau sought to find out in his new documentary That Sugar Film.

Following the lead of films like Morgan Spurlock’s Super Size Me, Gameau decided to see what would happen to his body after 60 days of a low-fat, high-sugar diet. These are the results that surprised us the most.

MORE: All the recipes you need to go sugar-free

It’s very easy to eat 40 teaspoons of sugar per day.
Yep, that’s the average amount of sugar Australians eat. For one breakfast, Gameau consumed 20 teaspoons of sugar – and that was from a cup of breakfast cereal, some low-fat yoghurt and apple juice. Scary stuff when you consider the World Health Organisation recommended we cut our daily added-sugar intake to 5 per cent of our total daily kilojoules. “What that means on a 2000 calorie (8400 kJ) per day diet is about six to eight teaspoons,” Gameau explains. “And considering we’re having somewhere between 30 and 40, that’s quite a dramatic drop.”

All kilojoules are not the same.
Even though Gameau had the same energy intake as his regular diet, he gained 8.5kg and 10 cm of visceral fat around his waist in 60 days, and developed fatty-liver disease. “Before I started, I had a very healthy diet,” says Gameau. “The main things I avoided were refined sugar and carbohydrates. I very rarely had white bread or pastas and made sure I had lots of healthy fats like avocado and nuts. I just felt better for it. That’s what shocked me the most during the experiment, my body just reacted very quickly.” Looking for a healthy energy intake? Consider the type of food. “Broccoli certainly doesn’t turn to fat in your liver the way sugar does,” he says. “It’s not about counting calories but being aware of the source and getting away from processed foods.”

GALLERY: What does 200 calories look like?

Sugar makes you moody
The side effect that shocked Gameau the most? His moods. “Because I ate so well before, my moods were being determined by the sugar. I’d be up when I’d have the sugar, and then I’d crash, and then I’d be up again. It was this kind of rollercoaster,” he says. “You have these kinds of foods, then your blood sugar levels rise very quickly, and then they disappear and when that happens your brain releases this chemical that can make people feel nervous, anxious, irritable.”

It’s never too late to turn your health around.
While Gameau’s experiment put his body well on the road to type-2 diabetes and obesity, he was able to turn his health markers around by going back to his old, healthy eating routine. “There’s a lot of going into the unknown but I had the confidence because I knew I was a better person without it,” he says. “As soon as I finished the film, just from going back to my normal diet, all of my fatty liver disease turned around, my heart disease risk changed, I lost 90 per cent of the weight doing very minimal exercise just from my nutrition.” The take away? It’s not all doom and gloom. “If you go back to eating the right foods again, conditions can be turned around just by diet and that’s the message we’ve got to get out there.”

That Sugar Film is touring cinemas around the country in March.

Related:

11 weird things sugar does to your body
Six alarming reasons you should avoid sugar