The 2019 Hamilton Award is a sweet reward for nutrition researcher Dr Lisa Te Morenga, for her internationally significant research on sugar.
It is easy to demonise sugar as ‘white death’, but while it gets blamed for a lot of things it turns out there is not always good evidence to back many of those claims up.
However, nutrition researcher Dr Lisa Te Morenga, from Victoria University of Wellington, who is a strong advocate for evidence-based decision-making, says this is beginning to change.
“I think we’re probably starting to understand sugar a little more than when I first started researching in this area … in 2011,” says Lisa.
Dr Te Morenga was the main author on an influential systematic review and meta-analysis published in the British Medical Journal in 2013. The study looked at high quality randomised dietary intervention trials and concluded that there was a clear link between free sugars in the diet and the risk of excessive weight gain.
She says this research has contributed “to increasing that understanding of the role of sugar in our health, and that role is not particularly positive - but perhaps not as toxic as others out there would have us believe.”
The systematic review was commissioned by the World Health Organisation (WHO) as it was developing recommendations for how much free sugar we should consume as part of our daily diet. Free sugars are added sugar, such as sugar in soft drinks and foods such as ketchup, as opposed to intrinsic sugars that are a naturally occurring component of many foods, such as fruit.
How much sugar should we eat?
In 2015, the WHO published new dietary guidelines for sugar recommending that adults and children reduce their daily intake of free sugars to less than 10 percent of their total energy intake, or no more than 12 teaspoons. Limiting the intake of free sugars also reduces the number of dental caries.
“It might seem really obvious to people now that, of course, high sugar diets are going to lead to weight gain, but really, before this meta-analysis came out it seemed a bit equivocal,” says Dr Te Morenga.
Dr Te Morenga says that sugary drinks are a significant source of empty calories, and that the more sugary drinks people consume the more likely they are to put on weight.
Dr Te Morenga says she is not anti-sugar. She believes there is a place and time to enjoy sugary treats, such as fruit juices and cakes, but she thinks we need to treat these as occasional treat foods rather than everyday food items.
In 2016, Dr Te Morenga was involved with the production of expert advice on sugar and health for New Zealand produced by the Royal Society - Te Apārangi.
How much saturated fat should we eat?
More recently, Dr Te Morenga has carried out a systematic review on saturated fat intake and its impact on various risk factors for cardiometabolic disease in children.
This review has been used by the WHO in the guidelines they are currently developing on dietary recommendations for how much saturated fat adults and children should have in their diet.
Dr Te Morenga says that saturated fat is basically any fat or oil that is solid at room temperature, for example butter, meat fat and coconut.
The WHO draft guidelines suggest that people should limit saturated fat to less than 10 percent of their total daily energy intake.
“In New Zealand we probably consume on average about 13 percent of our calories from fat, so it’s not a huge reduction that people should make,” says Dr Te Morenga.
Find out more about Lisa Te Morenga’s research
Listen to the podcast to hear Dr Te Morenga discussing her sugar research, as well as new work into carbohydrates and the value of whole foods as part of a healthy diet.
Dr Te Morenga’s whakapapa is Ngapuhi, Ngāti Whātua and Te Rarawa. She lectures in Māori Health at Victoria University of Wellington and is involved with two Centres of Research Excellence: the Riddet Institute and Ngā Pae o te Māramatanga. In the interview she also talks about her views on Māori science and Mātauranga Māori.
In 2018 she was awarded a Rutherford Discovery Fellowship by the Royal Society -Te Apārangi.
The Hamilton Award is an early career research excellence award given by the Royal Society - Te Apārangi. The 2019 award recognises Dr Te Morenga for providing strong evidence that sugar in our diet contributes to weight gain.
More on the 2019 Research Honours winners
You can find the full list of 2019 award winners on the Royal Society – Te Apārangi website.