Individuals with Prader–Willi syndrome (PWS) in Australia consume diets aligned with national guidelines but exceed energy needs by 85%–90%, contributing to high obesity rates. Despite adequate intake of most nutrients, saturated fat and sodium were excessive, while calcium, iron and magnesium were inadequate. PWS-specific, energy-restricted diets are essential for better health outcomes.
ABSTRACT
Introduction
Dietary management is essential to prevent obesity and related complications in people with Prader–Willi syndrome (PWS). Although PWS guidelines recommend controlled, energy-restricted diets, little is known about the diets of people with PWS in Australia. This study investigated nutritional adequacy and diet quality in this population.
Methods
Diets of 18 adolescents and 26 adults participating in a clinical trial of an exercise intervention were assessed using the Australian Eating Survey Food Frequency Questionnaire. Diet alignment with the Australian Dietary Guidelines was determined. Energy requirements were calculated from height and energy needs, based on body mass index (BMI) z-score or BMI category. Diet quality was measured using the Australian Recommended Food Score. Statistical analyses compared outcomes between BMI categories, age groups and living arrangements.
Results
Ten adolescents and 21 adults were overweight or obese. Diets exceeded recommended energy intakes by 85%–90%, but on average aligned with Australian Dietary Guidelines. People above the healthy weight range were less likely to be within the PWS-recommended energy intake (p < 0.01). Most met essential nutrient recommendations, except for excessive saturated fat and sodium, and inadequate calcium, iron and magnesium intake. The majority met recommended servings for three of the core food groups, with exceptions of grains and dairy. More than half of the participants exceeded recommended limits for discretionary food. People in supervised residences showed a higher vegetable intake but lower fruit variety. Overall diet quality and BMI distribution did not differ between living arrangements.
Conclusion
This study highlights the dietary patterns and the high prevalence of overweight and obesity in Australians with PWS. Overweight and obesity occurred despite strong adherence to Australian healthy dietary guidelines. PWS appropriate energy-restricted diets, including low-fat, calcium and iron-rich foods, are recommended to enhance health outcomes.
Journal of Human Nutrition and Dietetics, Volume 39, Issue 1, February 2026. Read More