Effects of dietary carbohydrate on 1,5-anhydroglucitol in a population without diabetes: results from the OmniCarb trial

5 years ago

Effects of dietary carbohydrate on 1,5-anhydroglucitol in a population without diabetes: results from the OmniCarb trial

E. R. Miller, E. Selvin, L. J. Appel, R. H. Christenson, F. M. Sacks, S. P. Juraschek

Aims To determine the effects of dietary changes in amount and type of carbohydrate on 1,5-anhydroglucitol levels. Methods We conducted an ancillary study to a completed, randomized clinical trial in overweight and obese adults without diabetes (N=159). Using a crossover design, participants were fed each one of four diets in turn for 5 weeks, with 2-week washout periods inbetween. The four diets were: high glycaemic index (≥65) with high proportion of carbohydrate (58% kcal) (GC); low glycaemic index (GI≤45) with low proportion of carbohydrate (40% kcal) (gc); low glycaemic index with high proportion of carbohydrate (gC); and high glycaemic index with low proportion of carbohydrate (Gc). Plasma 1,5-anhydroglucitol levels were measured at baseline and after each feeding period. Results At baseline, participants had a mean age of 53 years (53% women, 52% non-Hispanic black, 50% obese). Their mean fasting glucose and 1,5-anhydroglucitol levels were 97 mg/dl (5.4 mmol/l) and 18.6 μg/mL (113.3 μmol/l), respectively. Compared with baseline, each of the four diets reduced 1,5-anhydroglucitol by a range of –2.4 to –3.7 μg/mL (–14.6 to –22.5 μmol/l); all P <0.001). Reducing either glycaemic index or proportion of carbohydrate lowered 1,5-anhydroglucitol levels. These effects were additive, such that reducing both glycaemic index and proportion of carbohydrates decreased 1,5-anhydroglucitol by –1.31 μg/mL [95% CI: –1.63, –0.99; P<0.001 or –8.0 (–9.9, –6.0) μmol/l]. Furthermore, these effects were confirmed in a subgroup of participants with 12-h glucose monitoring and no documented hyperglycaemia (fasting glucose <160 mg/dl or 8.9 mmol/l). Conclusions Both type and amount of dietary carbohydrate affect 1,5-anhydroglucitol plasma concentrations in adults without diabetes. This finding contradicts the long-standing notion that 1,5-anhydroglucitol remains at constant concentrations in the blood in the absence of hyperglycaemic excursions. (Clinical trials registry number: NCT00051350)

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1111/dme.13391