Will a sweet tooth lead to obesity?

Sugar, or rather the elimination of it, is the dietary craze du jour. There are calls for Australia to follow the lead of countries such as the UK, Mexico and Hungary and introduce a tax on sugary drinks. But does having a sweet tooth mean you are more prone to being overweight or obese?

Scientists with Deakin University’s Centre for Advanced Sensory Science (CASS) conducted experiments using a range of sweeteners and found there is not a strong connection between sweet taste, diet and body size.

The results from the study suggest that sweetness is not necessarily what drives people to eat the types of food that can lead to weight problems, said the head of CASS, Professor Russell Keast.

“The relationship between sweet taste, food intake and overweight/obesity has been controversial, as studies in this area have not come up with consistent findings. That we found that sweet taste, measured using many different methods, was not associated with BMI or waist measurements is really not that surprising,” Professor Keast said.

“Consumers have the choice of foods which taste sweet but don’t have the energy from sugar through the use of low-calorie sweeteners. Soft drinks are a good example — one may contain lots of energy, the other none, but they are both equally sweet. Consumers can get their sweet buzz without the energy.”

Professor Keast said that considering the study results in light of a potential sugar tax is “intriguing”.

“One school of thought would be that since there is no association between how we perceive sugars and BMI or waist measurements, singling out sugar is not warranted, so the focus should be more on the whole diet,” he said.

“An alternate view is any initiative that reduces consumption of nutrient-void, sugar-rich foods, for example, sugar-sweetened beverages, has the potential to benefit public health. And certainly, any initiative that helps reduce children’s consumption of drinks high in sugar is also positive.”

During this study, participants tasted samples of a range of commercially available sweeteners, from natural sugars to artificial sweeteners. Multiple measures of sweet taste were assessed at a range of intensities. Height, weight and waist were measured and participants also completed questionnaires on their food intake.

PhD student Julia Low, who ran the study, said one interesting result was that perceived sweetness was found to be weakly to moderately associated with total energy intake.

“So the more sweetness you experience from a range of sweeteners, the more likely you were to have a higher energy diet,” Low said.

“The continued increase in the worldwide rate of nutrition-related chronic illness, such as obesity, demands an increased understanding of the drivers of food intake,” Professor Keast said.

“Taste is undoubtedly one driver of food intake, but the lack of association between sweet taste and BMI reinforces the complexity in developing effective strategies to reduce obesity. We certainly need a better understanding of high-intensity sweeteners in the food supply and the role they may play in weight maintenance.”

The study, titled ‘The association between sweet taste function, anthropometry, and dietary intake in adults’, is published online in the international journal Nutrients.