Late-breaking abstracts VIth conference of the International Society for Trace Element Research in Humans (ISTERH), Québec City, Canada, September 7–12, 2002
- Publisher
- John Wiley and Sons
- Year
- 2003
- Tongue
- English
- Weight
- 177 KB
- Volume
- 16
- Category
- Article
- ISSN
- 0896-548X
No coin nor oath required. For personal study only.
✦ Synopsis
Increased intake of chromium has been shown to lead to improvements in glucose, insulin, lipids and related variables in studies involving humans, experimental and farm animals. However, the results are often variable depending not only upon the selection of subjects but also dietary conditions and the form of supplemental Cr used. We determined the absorption of Cr in four forms in 57 subjects with type 2 diabetes mellitus. Subjects were divided randomly into 4 groups and given 200 lg of Cr/d as Cr chloride, Cr nicotinate, Cr nicotinateglycine-cysteine-glutamic acid or Cr picolinate in capsules containing a starch filler. Each subject received a placebo or Cr for three months in random order. Chromium absorption, based upon urinary Cr losses, was similar during the placebo and Cr-supplemented periods for all but the subjects receiving the Cr picolinate. We have subsequently shown that the forms of Cr that were not absorbed were unstable when mixed with starch and were converted to an inert form within one month. To find a Cr supplement that is stable, water soluble and absorbed well, we tested a number of Cr complexes. Complexes with the greatest absorption that were also stable were those containing histidine. We have synthesized a Cr trihistidine complex that is water soluble, stable and absorbed better than Cr picolinate, the form most often used to improve Cr nutrition. Daily urinary Cr losses for 6 subjects consuming 200 lg of Cr as Cr trihistidine increased from basal levels of 0.07 ± 0.02 to 3.10 ± 0.32 lg compared with 1.60 ± 0.16 lg for Cr tripicolinate in the first 24 hours following intake. Absorption was similar more than one year later when the Cr histidine complex was mixed with gelatin suitable for making Cr capsules. These data demonstrate that urinary Cr losses need to be determined since stability and absorption of the Cr complexes varies widely and may be responsible for the variability in some of the Cr supplementation studies. Chromium histidine is absorbed better than any of the Cr complexes currently available, is stable and may be used to improve Cr nutrition.
LB.