Scientific Resources

Sugar consumption is one of the largest and most preventable contributors to obesity, Type 2 Diabetes and Heart Disease. We’ve collated some of the key evidence underpinning the health risks associated with the consumption of added sugar below. 

Reducing sugar intake can prevent dental disease 

Sugar is well recognised as by far the most important dietary factor in the development of dental caries, the leading cause of tooth loss. The bacteria in our mouths combines with sugar from the food and drink we consume to produce acid. When we eat too much sugar too often, this acid will dissolve the tooth enamel and dental cavities and eventually tooth extraction.  

A startling 50% of children aged 12 years old have tooth decay in their adult teeth [1]. Dental research now supports reducing sugar intake to as low as 3% of total daily energy intake [2]. This is below the level recommended by the WHO and reflects the unequivocal link between sugar consumption and tooth decay.  

1] AIHW & Dental Statistics & Research Unit, Australian Reasearch Centre for Population Oral Health, University Of Adelaide.  

2] Sheiham A & James W.P.T (2014) A new understanding of the relationship between sugars, dental caries and fluoride use: implications for limits on sugars consumption. This review provides evidence to support sugar as the most important dietary factor in the development of tooth decay, and highlights the cumulative effect of sugar consumption over a lifetime on dental health. When teeth were exposed to sugars for more than three years, tooth decay or cavities occurred in teeth of children when sugar intakes were relatively low, just 2–3% of the total daily energy intake.  

 

3] Moynihan P & Kelly S. (2014) Effect on caries of restricting sugars intake: systematic review to update WHO guidelines. This comprehensive systematic review investigated the association between sugar intake and tooth decay. The findings show a clear and consistent causal relationship between free sugar and tooth decay in adults and children. Of the studies reviewed, all of those in adults and most of the studies in children reported a positive association between sugars and tooth decay. 

4] Ruottinen S, Karjalainen S, Pienihakkinen K, Lagstrom H, Niinikoski H, Salminen M, Ronnemaa T, Simell O (2004) Sucrose intake since infancy and dental health in 10-year-old children.

This study compared tooth decay status in children with high sugar consumption; exceeding the WHO recommended level of 10% of energy intake, with those with the lowest sugar intake. They reported that those children in the low-sugar intake group had on average 50% less dental disease experience than children in the high-sugar-intake group.

 

Sugar & the obesity crisis 

Obesity is becoming one of the greatest health challenges facing Australia. 

More than two thirds of Australians are overweight or obese and the rate of obesity has grown from 19% to 28% over the last two decades [1]. By 2025 it is estimated one third of children will be overweight and obese [2]. Consuming too much sugar is making the nation fatter, bringing with it the growing burden of chronic diseases such as Type 2 Diabetes, Cardiovascular, Liver and Kidney Disease. The cost of obesity to the nation is projected to be in excess of $87.5 billion over the next ten years if no action is taken [3].

The consumption of added sugar in our diet causes weight gain by providing excessive and empty calories which offer no true nutritional value. There is a strong body of evidence to support the link between sugar consumption and weight gain. The large scale review commissioned by the World Health Organization (WHO) published in 2013 [4] provided sufficient evidence to form the basis of WHO guidelines that recommend added sugar should make up no more than 10% of total calorie intake. More recently there have been randomized controlled trials showing the impact of sugar-sweetened beverages on weight gain in adolescents [5]. This supports a number of prospective cohort studies which confirm the link between sugars-sweetened beverages and increased obesity rates [6]. 

1] Australian Health Survey: Updated Results, 2011-2012  (Australian Bureau of Statistics) 

2] Walls H.L, Magliano D.J, Stevenson C.E, Backholer K, Mannan H.R, Shaw J.E, Peeters A. (2012) Projected progression of the Prevalence of Obesity in Australia. 

3] Weighing the cost of Obesity: A case for action – PwC Australia (2015) 

4] Te Morenga L, Mallard S, Mann J. (2013) Dietary sugars and body weight: systematic review and meta-analyses of randomized controlled trials and cohort studies. This large-scale systematic analysis commissioned by the World Health Organization provides consistent evidence that diets higher in added sugars resulted weight gain in adults.  The findings identified decreased intake of added sugars significantly reduced body weight by 0.80 kg, and increased consumption led to a comparable weight increase of 0.75 kg.  

5] de Ruyter J.C, Olthof M.R, Seidell J.C, Katan M.B. (2012) A trial of sugar-free or sugar sweetened beverages and body weight in children. This double blind randomized controlled trial showed significantly reduced weight gain and body fat in healthy children when they consumed a masked replacement of a sugar-free beverage compared to those consuming a sugary drink.  

6] Hu, F.B. (2013) Pro v Con Debate: Role of sugar sweetened beverages in obesity

Resolved: there is sufficient scientific evidence that decreasing sugar-sweetened beverage consumption will reduce the prevalence of obesity and obesity-related diseases. This systematic review goes a step further by evaluating evidence against criteria to prove there is a cause-effect relationship between sugary drinks and obesity. This study provides evidence that consumption of sugar-sweetened drinks causes excess weight gain and that sugary drinks are unique dietary contributors to obesity and Type 2 Diabetes.

 

Added Sugar Consumption & Type 2 Diabetes  

1.7 million Australians have diabetes; a major cause of blindness, kidney failure, heart attacks, stroke and lower limb amputation. Each day 280 Australians develop are diagnosed with diabetes, that’s one person every 5 minutes. Twelve people undergo diabetes related amputations in Australia every day (1).  

Diabetes occurs when the body is not able to control the amount of glucose in the blood, often causing the blood sugar level to remain abnormally high. Insulin is the hormone released to control how much glucose is taken from the blood stream by cells to be used for energy production. Diabetes develops when the body cannot produce sufficient insulin (Type 1) or when it becomes resistant to the effects of insulin (Type 2).  

High sugar diets have been identified to cause weight gain which increases the risk of Type 2 Diabetes [2]. There is also growing evidence to support the toxic effects of sugar as a direct driver of insulin resistance and metabolic syndrome independent of weight gain [3-5].  

1] Diabetes Australia, 2016 

2] Basu S, Yoffe P, Hills N, Lustig R.H. (2013) The Relationship Of Sugar to population-level Diabetes prevalence: An Econometric Analysis of Repeated Cross Sectional Data. Using data from 175 countries, this study provides evidence of the link between sugar availability and the prevalence of Type 2 Diabetes. For every excess 150 calories consumed (about one can of sugary drink) there was a 1% increase in prevalence of Type 2 Diabetes when compared to 150 calories consumed from another source. 

3] Imamura F, O’Connor L, Ye Z, Mursu J, Hayashino Y, Bhupathiraju S.N, Forouhi N.G.

(2015) Consumption of sugar sweetened beverages, artificially sweetened beverages, and fruit juice and incidence of Type 2 diabetes: systematic review, meta analysis and estimation of population attributable fraction. A comprehensive systematic review that provides evidence of a link between the consumption of sugar sweetened beverages and Type 2 Diabetes. The consumption a sugar-sweetened beverage by one serving a day was associated with an 18% greater incidence of Type 2 Diabetes the results were adjusted to account for the effects of weight gain the incidence still increased by 13% per serving. 

Malik V.S, Popkin B.M, Bray G.A, Despres J.P, Willett W.C, Hu F.B. (2010) Sugar-sweetened beverages and risk of metabolic syndrome and type 2 diabetes: a meta-analysis. This meta-analysis included 310,819 participants and evaluated 15,043 cases of Type 2 Diabetes. It showed the risk of developing Type 2 Diabetes increased by 26% in those with the higher consumption of sugar sweetened beverages (1-2 drink serving a day) compared to those in the lowest category (none or less than one drink serving a month). 

Greenwood D.C, Threapleton D.E, Evans C.E.L, Cleghorn C.L, Nykjaer C, Woodhead C, Burley V.J. (2014) Association between sugar-sweetened and artificially sweetened soft drinks and type 2 diabetes: systematic review and dose–response meta-analysis of prospective studies. A systematic review which identified a clear positive association between the intake of sugar sweetened beverages and incidence of Type 2 Diabetes. An increase intake of sugar sweetened beverage of 330mls a day was found to be associated with an increased risk of developing Type 2 Diabetes by approximately 20%.

 

Cardiovascular disease risk and added sugar intake.  

A high sugar diet has been linked to increased risk of heart disease mortality [1-2]. Consuming high levels of added sugar are associated with risk factors for heart disease such as weight gain and raised blood pressure [3]. Excessive dietary glucose and fructose have been shown to increase the production and accumulation of fatty cells in the liver and bloodstream which is inked to both cardiovasucluar disease and kidney and liver disease [4]. Non-alcoholic fatty liver disease is one of the major causes of chronic liver disease and is associated with the development of Type 2 Diabetes and coronary heart disease. 

1] Yang Q, Zhang Z, Gregg E.W, Flanders, WD, Merritt R, MA; Hu F.B. (2014) Added Sugar Intake and Cardiovascular Diseases Mortality Among US Adults. Results from this study showed an association between higher intakes of added sugar and the risk of death from cardiovascular disease. Those who consumed  between 17-21% of their daily energy from added sugar had a 38% higher risk of death from cardiovascular disease compared to those who consumed less than 10% of their calories from added sugar. Those who consumed 25% of their calories from added sugar trebled their risk of death from cardiovascular disease when compared to those who consumed less than 10% of their calories from added sugar.  

2] Duffey K.J, Gordon-Larsen P, Steffen L.M, Jacobs D.R, Popkin B.M. (2010) Drinking caloric beverages increases the risk of adverse cardio-metabolic outcomes in the Coronary Artery Risk Development in Young Adults (CARDIA) Study.  This study examined the relationship between the consumption of different types of beverages and their association with risk factors for cardio-metabolic disease. The findings suggest higher consumption of sugar-sweetened beverages are associated with an increased risk of cardio-metabolic disease. 

3] Xi B, Huang Y, Reilly K.H, Li S, Zheng R, Barrio-Lopez M.T, Martinez-Gonzalez M.A, Zhouet D. (2015) Sugar-sweetened beverages and risk of hypertension and CVD: a dose-response meta-analysis. This study investigated the association between the consumption of added sugar and the risk of high blood pressure, cardiovascular disease and stroke. A higher consumption of sugar-sweetened beverage was associated with a higher risk of hypertension and coronary heart disease, although not with the risk of stroke. 

4] Schwarz J.M, Noworolski S.M, Wen M.J, Dyachenko A, Prior J.L, Weinberg M.E, Herraiz L.A, Tai V.W, Bergeron N, Bersot T.P, Rao M.N, Schambelan M, Mulligan K. (2015) Effect of a High-Fructose Weight-Maintaining Diet on Lipogenesis and Liver Fat. Research as to the exact role of dietary fructose in the development of chronic disease is continuing to grow. This small-scale experimental study identified an increase in fatty acid synthesis and liver fat in healthy men when on a high fructose diet, independent of weight gain.