Breath carbon stable isotope ratios identify changes in energy balance and substrate utilization in humans

L D Whigham1, D E Butz2, L K Johnson3

  • 1USDA ARS Human Nutrition Research Center, Grand Forks, ND, USA and University of Wisconsin-Madison, Madison, WI, USA at time of work; Paso del Norte Institute for Healthy Living, El Paso, TX, USA at time of publication.

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