1. ¹Rowe Program in Genetics, Department of Pediatrics, Division of Clinical Nutrition, Endocrinology and Vascular Biology, and Section of Neurobiology, Physiology, and Behavior, Davis, California, USA
2. ²Department of Nutrition, University of California, Davis, California, USA

Correspondence: Craig H. Warden (chwarden@ucdavis.edu)

Abstract

The workshop reviewed the literature indicating that natural alleles influence a substantial percentage of responses to nutrition and exercise in both humans and animal models. Human genetic studies provide evidence that body weight response to over- and underfeeding and to exercise is associated with specific genes. Studies in animal models, primarily rodents, prove the genetic control of responsiveness to diet and exercise and provide the tools to examine specific mechanisms. Limitations of the animal literature include lack of studies of allelic contributions to weight loss in response to diet restriction and data on evidence-based diets.

Discussion of the relative merits of sample size constraints vs. precision of phenotype measures in human genetic studies concluded that imprecise measures such as body weight and body mass index identify different genes than will specific measures of fat mass. Validation and limitations of whole genome association studies in humans was discussed, as was the role of animal models in discovery and mechanistic studies of gene/nutrition/exercise interactions.

The workshop concluded that genetics has a substantial impact on responses to both diet and exercise. However, current knowledge does not allow individual diet and exercise recommendations. New resources and technologies, including cost-effective phenotyping for humans and whole genome sequencing in both humans and rodents, are needed.