15 gram method: The simple sugar rule that helped me drop weight

From fat to Fitz

SMH writer Peter FitzSimons explains the simple changes he made to his diet and lifestyle to shed a massive 45 kilos in body weight.

When I hired an expensive personal trainer, he gave me a simple trick to deciphering confusing food labels that's stayed with me ever since: never eat anything with more than 15g per 100g of sugar.

It saw me cut out foods I presumed were healthy from their star rating or marketing, including cereal bars and protein bars.

I changed up my breakfast entirely – and lost weight.

So how does the 15-gram rule withstand further scrutiny?

Accredited practising dietician Joel Feren says it's bang on the money:

"According to the we should be choosing products with 15g of sugar per 100g [or less]," Feren says.

The rule has caveats, however.

Nutritionist and health coach Lulu Cook tells me: "Many nutritious foods are naturally higher in sugar than the proposed 15g/100g limit. Cutting them out entirely - especially fruit - would be detrimental to health."

But for processed foods she concedes 15g is a sensible limit.


Dr Kieron Rooney from Sydney University's Faculty of Health Sciences says a tougher limit would likely be needed for beverages.

"A problem I have with the 15g rule is that soft drinks still make it in the diet. Most sugar sweetened beverages have about 10 grams (of sugar) per 100 millilitres. Any sugar-cutting plan that still allows for the consumption of sugar-sweetened beverages is not a good long-term plan."

Nutrition and educator JR Fletcher says he would recommend an eight gram limit for dairy products.

He stresses that "low-sugar content" should equate to having less than 5g per 100g; 5-15g per 100g is medium sugar content, and above 15g is high."

Surprise fails

What are the surprising foods that fail the test?

Fruit-packed smoothies or shakes can easily catch people out, says accredited practising dietician and nutritionist Sanchia Parker.

"Taking time to eat the ingredients of a smoothie instead of drinking it allows your body to register it's no longer hungry."

Feren suggests swapping high-sugar sauces such as bolognese for their low-sugar cousin: passata.

Parker says swap tomato sauce (25 per cent sugar) or barbecue sauce (a whopping 54 per cent sugar) for salsa.

"Even sauce labelled "hot chilli" (not sweet chilli), will contain around 25-30 per cent sugar," she warns.

Beware, also, that deceptive label 'healthy'. Often, food manufacturers can't back it up.

"Foods marketed as "healthy" are a trap for eating more sugar," Parker says.

"Granola is marketed as a healthy cereal option but one serve (50g) can contain 10-15 grams of sugar due to the addition of extra sweeteners and dried fruit. Compare this to rolled oats: just 0.1g sugar.

"Also be mindful of the 'healthy' protein bars, muesli bars and fruit bars. Ingredients often contain three or four different types of sugar that sound healthy but are just adding excess calories."

Parker warns there are (non-diastatic malt, anyone?).

"Food manufacturers love it because they can trick us into thinking their food is healthier than it is because hey, who's going to know that mannose or panocha count as sugar?" she says.

How to navigate daily meals under 15g sugar

Many cereals are the worst offenders for going over the 15g limit - start checking the back of packets, and you'll be as dismayed as I was.

Feren suggests healthier breakfasts make a big difference.

"Wholegrain breads, oats, and cereals like Weet-Bix, Vita Brits, Guardian, and fruit-free or nut-based mueslis."

Parker suggests sprinkling cinnamon over your cereal or in your coffee instead of sugar.

"A teaspoon contains a little sugar (0.5g) but far less than a teaspoon of sugar at 4g."

She also has tips for the rest of the day.

"Stick to mostly fresh, whole foods and you'll naturally be eating less sugar. So think lean protein (chicken, beef, pork), nuts, legumes, eggs, dairy, fresh fruit and vegetables.

"Most of these foods don't actually have a nutrition label – a good sign you're eating something healthy / low sugar."

Is sugar really the devil?

Sugar is the current bete noir of all foods, but Joel Feren feels it may have been over-egged.

"No nutrient is poison; not even sugar. We eat foods, not single nutrients. Often we lose sight of the big picture when we focus on just one element like fat or sugar.

"While it's fashionable to lay the blame on sugar for our expanding waistlines, it isn't entirely fair."

Parker agrees that we need to keep the sugar-avoidance obsession somewhat in check.

"It can be extremist. I've had clients who cut out all fruit, sweet-corn, and dairy because they believe there's too much sugar in it," she says.

"There's definitely some fear-mongering that turns an innocent banana into the devil's ambrosia."

Dr Rooney says the 15/100g rule is a starting point, but it depends on the context of your overall diet.

"It's total sugar intake we need to be concerned about - not just how much we're eating in each serve."

He agrees with Parker that the best solution is just to keep it simple.

"If you're standing in a supermarket aisle trying to do some mental arithmetic to determine if a product in a box can or cannot be consumed on the basis of a finite level of sugar content in the ingredients list, you've already lost. 

"Here's a simpler rule. Put it down. Head to the colourful display of fresh fruit and veges right next to the entry of the supermarket. Pick something from there."