Chromium and Glucose Tolerance Factor
As originally defined, glucose tolerance factor (GTF) is a material absent from Torula yeast that when fed to rats on a Torula yeast diet reverses apparent glucose intolerance in the rats. Early study on glucose tolerance factor equated the term with chromic ion. However, the term “glucose tolerance factor” was later used to refer to a material extracted and partially purified from brewer’s yeast. The original studies have been shown to be methodologically flawed, and material from brewer’s yeast has been shown to be an artifact. Given the considerable confusion over the name GTF and the history of GTF studies, the terms “glucose tolerance factor” and “GTF” should no longer be used use in chromium nutritional and biochemical research.
Initial Reports of a Glucose Tolerance Factor
The fields of Cr nutrition and Cr biochemistry had their beginnings in 1955 when Walter Mertz and Klaus Schwarz fed rats a semipurified Torulayeast–based...
- Vincent JB, Stallings D (2007) Introduction: a history of chromium studies (1955–1995). In: Vincent J (ed) The nutritional biochemistry of chromium(III). Elsevier, AmsterdamGoogle Scholar