Measuring the glycemic index of foods: interlaboratory study.
Artikel i vetenskaplig tidskrift, 2008

BACKGROUND: Many laboratories offer glycemic index (GI) services. OBJECTIVE: We assessed the performance of the method used to measure GI. DESIGN: The GI of cheese-puffs and fruit-leather (centrally provided) was measured in 28 laboratories (n=311 subjects) by using the FAO/WHO method. The laboratories reported the results of their calculations and sent the raw data for recalculation centrally. RESULTS: Values for the incremental area under the curve (AUC) reported by 54% of the laboratories differed from central calculations. Because of this and other differences in data analysis, 19% of reported food GI values differed by >5 units from those calculated centrally. GI values in individual subjects were unrelated to age, sex, ethnicity, body mass index, or AUC but were negatively related to within-individual variation (P=0.033) expressed as the CV of the AUC for repeated reference food tests (refCV). The between-laboratory GI values (mean+/-SD) for cheese-puffs and fruit-leather were 74.3+/-10.5 and 33.2+/-7.2, respectively. The mean laboratory GI was related to refCV (P=0.003) and the type of restrictions on alcohol consumption before the test (P=0.006, r2=0.509 for model). The within-laboratory SD of GI was related to refCV (P<0.001), the glucose analysis method (P=0.010), whether glucose measures were duplicated (P=0.008), and restrictions on dinner the night before (P=0.013, r2=0.810 for model). CONCLUSIONS: The between-laboratory SD of the GI values is approximately 9. Standardized data analysis and low within-subject variation (refCV<30%) are required for accuracy. The results suggest that common misconceptions exist about which factors do and do not need to be controlled to improve precision. Controlled studies and cost-benefit analyses are needed to optimize GI methodology. The trial was registered at clinicaltrials.gov as NCT00260858.

Adolescent

Adult

classification

Sensitivity and Specificity

Reference Values

Humans

Blood Glucose

Laboratory Techniques and Procedures

Glycemic Index

Middle Aged

Female

Male

Glucose Tolerance Test

metabolism

Reproducibility of Results

standards

Food

Area Under Curve

Cross-Over Studies

Food Analysis

standards

metabolism

Dietary Carbohydrates

Aged

Författare

Thomas M S Wolever

Jennie C Brand-Miller

John Abernethy

Arne Astrup

Fiona Atkinson

Mette Axelsen

Göteborgs universitet

Inger Björck

Furio Brighenti

Rachel Brown

Audrey Brynes

M Cristina Casiraghi

Murielle Cazaubiel

Linda Dahlqvist

Elizabeth Delport

Gareth S Denyer

Daniela Erba

Gary Frost

Yvonne Granfeldt

Shelagh Hampton

Valerie A Hart

Katja A Hätönen

C Jeya Henry

Steve Hertzler

Sarah Hull

Johann Jerling

Kelly L Johnston

Helen Lightowler

Neil Mann

Linda Morgan

Leonora N Panlasigui

Christine Pelkman

Tracy Perry

Andreas F H Pfeiffer

Marlien Pieters

D Dan Ramdath

Rayna T Ramsingh

S Daniel Robert

Carol Robinson

Essi Sarkkinen

Francesca Scazzina

Dave Clark D Sison

Birgitte Sloth

Jane Staniforth

Niina Tapola

Liisa M Valsta

Inge Verkooijen

Martin O Weickert

Antje R Weseler

Paul Wilkie

American Journal of Clinical Nutrition

0002-9165 (ISSN)

Vol. 87 1 247S-257S

Ämneskategorier

Endokrinologi och diabetes

Klinisk medicin

MEDICIN OCH HÄLSOVETENSKAP

Näringslära

PubMed

18175765

Mer information

Skapat

2017-10-10