The Dietary Science Foundation
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A major challenge for dietary science research is that study participants sometimes fail to report things they eat, and especially foods that are considered to be unhealthy. The Dietary Science Foundation is awarding 30,000 euros to researchers at Lund University who will test a new, more objective method of tracking participant sugar consumption. They will measure sucrose levels in the urine, then analyze how sugar intake affects weight.
Many of the world’s largest dietary studies have built on self-reporting by participants about what they have eaten, because food intake is difficult to measure in any other way. Researchers have then used that information to analyze how different dietary habits or foods affect the risk of developing different diseases.
Media reporting about certain foods being dangerous are often based on these types of studies. But it is well known that this kind of science has a serious flaw: much of what slips down people’s throats is never reported. Which means that the results of the study run the risk of being misleading.
“For example, some studies show that participants tend to underreport the consumption of things they perceive to be unhealthy. Studies also show that the more someone weighs, the more they tend to under-report,” according to Stina Ramne, doctoral student at the Department of Nutrition Epidemiology at Lund University.
The Dietary Science Foundation has just allocated 30,000 euros to a project where Stina Ramne, her supervisor Emily Sonestedt, associate professor of nutrition epidemiology, and Anne Raben, professor of obesity research at the University of Copenhagen, will follow participant sugar consumption instead, by measuring the amount of sucrose in the urine.
When we eat sugar, sucrose, in sweet foods, the body breaks down most of it into the simple sugars glucose and fructose. But a very small amount of sucrose enters the bloodstream and is excreted in the urine.
“Studies where people’s sugar intake was controlled have showed a strong correlation with the amount of sugar found in 24-hour urine samples,” Stina Ramne says.
Since the amount of sucrose and fructose in urine specimens appears to reflect how much sugar people eat, researchers have recently started using this method as a more objective way to measure sugar consumption. For example, British researchers have found a link between the level of sucrose and fructose in urine samples and a higher risk of obesity. If the self-reported sugar intake of participants is analyzed instead, the correlation is negative.
Stina Ramne and Emily Sonestedt will now analyze urine samples that have been collected through the PREVIEW study. This study is being conducted in eight different countries with the purpose of preventing diabetes.
“It’s unusual to collect 24-hour urine samples in studies, but it’s been done in this one. The samples provide a gold mine of information for us to use,” says Emily Sonestedt.
The study has just ended, and the results are not yet published. 2,326 people with prediabetes restricted calories for two-months and were then randomized into two groups. For three years one group followed a low-glycemic index (GI) diet with a high protein intake, while the other group ate more carbohydrates with a higher GI, and a moderate protein intake. Both diet groups were further divided into two different exercise groups; one that exercised vigorously, the other more moderately.
24-hour urine samples were collected from the participants on several occasions. Stina Ramne will analyze the amount of sucrose in about 900 of these samples from the nearly 400 PREVIEW participants in Copenhagen.
“Neither of the dietary treatments in the study focused specifically on sugar. But it will be interesting to study the importance of sugar intake for maintaining weight loss,” says Stina Ramne.
She will also compare how closely the amount of sugar in the urine corresponds to the amount participants reported that they ate
The Dietary Science Foundation’s scientific advisory board expects the study to make a valuable contribution to dietary science, which has long been built upon self-reported data. Improving the quality of research in this field requires a more objective way of measuring what participants actually eat. Stina Ramnes and Emily Sonestedt’s project is therefore of vital importance.
A big thank you to everyone who supports the Dietary Science Foundation. Your contributions made this project possible! We are excited about the results, which are expected to be ready in the fall of 2020. The Dietary Science Foundation will support an additional project this year. We will reveal what project it is tomorrow, but we can already tell you that it has to do with type 2-diabetes. Stay tuned!