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Currently submitted to: JMIR mHealth and uHealth

Date Submitted: Sep 26, 2019
Open Peer Review Period: Sep 25, 2019 - Nov 18, 2019
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New dimensions in precision health; validating a nutrition tracking technology

  • Sarah Dimitratos; 
  • John Bruce German; 
  • Sara Schaefer; 



Wearable and mobile sensors have the potential to provide utility in precision nutrition research and practice, but few reliable tools can obtain accurate and precise measurement of diet and nutrition.


A study was conducted to assess the ability of wearable body sensors to monitor the dietary intake and metabolic responses of 25 free-living adult participants during two 14-day testing periods.


For each testing period, participants were asked to use two wearable health technologies simultaneously; the GoBe2™ wristband and accompanying smartphone app for estimating daily calorie intake and the FreeStyle Libre™ Pro System continuous glucose monitor (CGM). The capability of the wristband technology to detect calorie intake (kcal/d) was validated by a reference method developed to directly measure participant dietary intake. The research team collaborated with a university dining facility to prepare and serve calibrated study meals and record each participant’s energy and macronutrient intake. The development and implementation of the dietary intake reference method within a normal free living population are described.


Participant calorie intake recorded by the wristband style of wearable devices was correlated with the reference measurements (Pearson’s coefficient = 0.34). Transient loss signal from sensor technologies even briefly varies across a normal population and is a major source of error in computing dietary intakes. CGM data were collected to examine and control for participant nonadherence to food reporting protocols; these are not factored into the present analyses.


This study documents the accuracy and utility of current state of the art of wristband based sensor devices and highlights the need for reliable, effective measurement tools to facilitate accurate, precision based technologies for personal dietary guidance and intervention.


Please cite as:

Dimitratos S, German JB, Schaefer S

New dimensions in precision health; validating a nutrition tracking technology

JMIR Preprints. 26/09/2019:16405

DOI: 10.2196/preprints.16405


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