Dietary Analysis – “Quitting” sugar by Tania Logan, Dietitian and Diabetes Educator

Christina ReynoldsDietetics, Dietetics & Diabetes Education

This final instalment of my analysis of popular dieting trends investigates whether it is necessary to “quit” sugar. In this article I’ll discuss what “quitting” sugar requires, analyse the scientific evidence available and give you my verdict on whether it is worthwhile or not.

The diet

Unless you have been living under a rock for the past 10 years, I’m sure you will have read or heard sugar called everything from “sweet poison” to “toxic”.  Supporters of this diet believe that sugar, or fructose particularly, is our enemy.  They believe it is an addictive drug that encourages us to eat more, makes us overweight and causes a plethora of health concerns.

“Quitting” sugar requires avoiding any foods that contain sugar.  These include:

  • Honey
  • All sugars including palm sugar and coconut sugar
  • Jams, including diet jams
  • Lollies and chocolate
  • Biscuits, cakes and other processed foods that contain added sugar
  • Sugar sweetened drinks like cordial and soft drink
  • Condiments that contain sugar including tomato sauce, mayonnaise and balsamic vinegar
  • Muesli and muesli bars
  • Flavoured yoghurt and other sweetened dairy products like custard and ice cream
  • Fruit – fresh fruit, dried fruit, tinned fruit and fruit juice

The evidence

There are in fact several different sugars in the diet and they are the building blocks of carbohydrate. These include monosaccharides, like glucose and fructose (the natural sugar in fruit), which are single molecules, as well as disaccharides, like sucrose (table sugar) and lactose (the natural sugar in dairy products), which are two monosaccharides linked together. 

Glucose is very important to the inner working of our bodies.  It is what our cells use for energy, particularly our brain.  Glucose is transported around the body in the blood stream.  A healthy body maintains a stable level of glucose in the blood at all times.  When glucose levels drop below this level, our body starts to react by feeling weak, shaky and dizzy.  This is a signal that the fuel tank is empty and the brain may not have enough glucose to continue functioning optimally.  This is extremely dangerous and is exactly what happens to people with diabetes when they are experiencing hypoglycaemia (low blood glucose levels).

It is hard to imagine that sugar can be “toxic” when our body needs it to survive.  Without adequate levels of glucose in our blood we will die. But what does the research say about sugar and its effect on weight and health?

Most of the research on the negative effects of sugar is generally only supported by animal studies where the amount of sugar fed to the laboratory animals is exponentially greater than what could possibly be consumed in a human diet.  The highest levels of human research have not shown that fructose is any different to other digestible forms of carbohydrate in terms of its effect on health.

Research regarding the effect of sugar on weight gain has shown that any effect of increased sugar intake is due to an excess energy intake rather than a unique aspect of how sugar is utilised by the body.  

The research on cardiovascular risk also suggests that any effect on increased blood pressure or lipids is due to excess energy intake resulting in weight gain, rather than from an effect of sugar itself.  There is also little direct evidence that sugar causes diabetes.

Evidence for sugar addiction has also been explored in research studies.  A recent review found that there is very little evidence of addiction behaviours to sugar in humans.  Findings from animal studies suggest that addiction behaviours are limited to situations of deprivation and limited access to sweet tasting or highly palatable foods, rather than the neurochemical effect of sugar.

There is an association between sugar sweetened drinks, like soft drink, and increased weight, cardiovascular risk and diabetes.  These drinks also appear to be a marker of a less healthy lifestyle and are also associated with increased energy intakes, lower levels of physical activity, higher rates of smoking and poor dietary intake.  It is therefore difficult to tell whether the overall dietary and lifestyle pattern is the problem, or the sugar sweetened drinks specifically.

Possible benefits

Despite the fact that sugar isn’t “toxic”, most of us do still eat too much of it.  The World Health Organisation recommends that the intake of added sugars is limited to less than 10% of total energy intake with the aim to decrease this to less than 5%.  For the average Australian, less than 10% equates to approximately 13 teaspoons of sugar each day.  One 375 ml can of soft drink contains approximately 10 teaspoons of sugar while one 50 g chocolate bar contains approximately 9 teaspoons of sugar. Neither provide nutritional value in the form of fibre, vitamins or minerals.

Reducing your intake of processed foods that are high in sugar can be beneficial.  Many of these foods provide excess energy and very little nutrients of value.  Decreasing your intake of these foods and replacing them with more nutritious, unprocessed foods can be useful.  Including plenty of vegetables and salads comprising legumes, fruit, nuts, wholegrain breads and cereals, reduced fat milk and yoghurt, as well as lean meat, chicken, fish and eggs will improve health and wellbeing.  

Possible side effects

Avoiding sugar can be confusing for many people and it imposes a set of rules that are not based on scientific evidence.  It also can create a “dieting mentality” and an unhealthy relationship with food. This can lead to stress, anxiety and depression in some people as they strive to achieve a “perfect”, healthy diet. These are features of orthorexia, which is an overwhelming preoccupation with eating only healthy, “clean” food and avoiding food that is considered impure.  It is estimated that 7 – 21% of the population may have this condition.

Some foods that contain sugar are an essential part of a healthy diet, providing many vitamins and minerals. Fruit contains the natural monosaccharide fructose.  It is a nutritious food that is an excellent source of fibre as well as many vitamins and minerals.  It is recommended we consume two pieces of fruit each day to reduce the risk of cardiovascular disease, type 2 diabetes and some cancers.  Yoghurt also contains the disaccharide lactose, as well as often some added sugars.  Yoghurt is a beneficial source of protein and calcium.  Poor calcium intake can increase the risk of osteoporosis.

In a nutshell

Sugar is not a “poison” or a “toxin” that must be totally eliminated from the diet.  A small amount of sugar is not harmful to our health, but we should be limiting our intake of added sugar.  There is no need to avoid fruit or dairy products.  

You can reduce your intake of added sugar by:  

  • Reducing the amount of sugar, honey, syrup or jam you add to your food and drinks
  • Reducing your intake of soft drink and other sugar sweetened drinks 
  • Reducing your intake of lollies and chocolates
  • Reducing your intake of high sugar, processed foods like biscuits and cakes
  • Choosing wholegrain breakfast cereals instead of processed cereals that contain added sugar

It is also important to focus on what we should be eating for good health and wellbeing.  Consider the whole food not just how much sugar it contains. Aim to increase your intake of good quality, less processed foods including:

  • Plenty of vegetables and salads including legumes
  • Fruit
  • Nuts and seeds
  • Wholegrain breads and cereals
  • Reduced fat milk and yoghurt
  • Lean meat, chicken, fish and eggs

If you would like help with developing healthy eating or lifestyle behaviours, or if you would like practical assistance for making any of these suggested changes to improve your health, please contact me. You can find my contact details and how to book an appointment on our website at

Share this Post