Salivary alpha-amylase copy number is not associated with weight trajectories and glycemic improvements following clinical weight loss: results from a 2-phase dietary intervention study

Armand Valsesia*, Sameer S. Kulkarni, Julien Marquis, Patricia Leone, Polina Mironova, Ondine Walter, Mads Fill Hjorth, Patrick Descombes, Jorg Hager, Wim H. Saris, Arne Astrup, Christian Darimont*, Nathan J. O'Callaghan*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review


Background: Several studies recently reported contradicting results regarding the link between amylase 1 (AMY1) copy numbers (CNs), obesity, and type 2 diabetes.

Objective: The aim of this study was to assess the impact of AMY1 CN on anthropometrics and glycemic outcomes in obese individuals following a 2-phase dietary weight loss intervention.

Methods: Using the paralog ratio test, AMY1 CNs were accurately measured in 761 obese individuals from the DiOGenes study. Subjects first underwent an 8-wk low-calorie diet (LCD, at 800 kcal/d) and then were randomly assigned to a 6-mo weight maintenance dietary (WMD) intervention with arms having different glycemic loads.

Results: At baseline, a modest association between AMY1 CN and BMI (P = 0.04) was observed. AMY1 CN was not associated with baseline glycemic variables. In addition, AMY1 CN was not associated with anthropometric or glycemic outcomes following either LCD or WMD. Interaction analyses between AMY1 CN and nutrient intake did not reveal any significant association with clinical parameters (at baseline and following LCD or WMD) or when testing gene x WMD interactions during the WMD phase.

Conclusion: In the absence of association with weight trajectories or glycemic improvements, the AMY1 CN cannot be considered as an important biomarker for response to a clinical weight loss and weight maintenance programs in overweight/obese subjects. This trial was registered at as NCT00390637.

Original languageEnglish
Pages (from-to)1029-1037
Number of pages9
JournalAmerican Journal of Clinical Nutrition
Issue number4
Publication statusPublished - Apr 2019


  • obesity
  • insulin resistance
  • low-calorie diet
  • copy number
  • AMY1
  • weight loss
  • GENE

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