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

Abstract

Background 1,5-anhydroglucitol (1,5-AG) is monosaccharide derived from foods that can be used to monitor hyperglycemic excursions in diabetes. Determinants of 1,5-AG in persons without diabetes are largely uncharacterized and the effects of dietary changes in amount and type of carbohydrates on 1,5-AG are unknown. 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 of four diets for 5-weeks with 2-week intervening washout periods. The four diets were: high glycemic index (GI≥65) with high %carb (58% kcal), low GI (GI≤45) with low %carb (40% kcal), low GI with high %carb; and high GI with low %carb. Plasma 1,5-AG was measured at baseline and after each feeding period. Results At baseline, participants were mean age 53 years (53% female, 52% non-Hispanic black, 50% obese). Mean fasting glucose and 1,5-AG were 97 mg/dL (5.4 mmol/L) and 18.6 μg/mL (113.3 μmol/L). Compared to baseline, each of the 4 randomized diets reduced 1,5-AG −2.4 to −3.7 μg/mL (−14.6 to −22.5 μmol/L); all P-values <0.001). Reducing either glycemic index or proportion of carbohydrates lowered 1,5-AG. These effects were additive, such that reducing both glycemic index and proportion carbohydrate decreased 1,5-AG by −1.31 μg/mL (−1.63, −0.99; P<0.001; −8.0; −9.9, −6.0 μmol/L). Furthermore, these effects were confirmed in a subgroup with 12 hour glucose monitoring and no documented hyperglycemia (fasting glucose <160 mg/dL or 8.9 mmol/L). Conclusions Both type and amount of dietary carbohydrates affect 1,5-AG plasma concentrations in adults without diabetes. This finding contradicts the long-standing notion that 1,5-AG remains at constant concentrations in the blood in the absence of hyperglycemic excursions.

Low 1,5-anhydroglucitol levels are associated with long-term cardiac mortality in acute coronary syndrome patients with hemoglobin A1c levels less than 7.0%

“…1,5-Anhydroglucitol (1,5-AG) is a monosaccharide found in most foods [17]. The concentration of 1,5-AG in blood and tissues is maintained constant due to reabsorption in the renal proximal tubule [17, 18].…”

“…The concentration of 1,5-AG in blood and tissues is maintained constant due to reabsorption in the renal proximal tubule [17, 18]. As excretion of glucose into the urine increases, reabsorption of 1,5-AG is inhibited competitively and the blood level of 1,5-AG decreases.…”

Effects of carbohydrate quality and amount on plasma lactate: results from the OmniCarb trial

“…Clinical care/Education/Nutrition carbohydrate amount nor GI improved insulin sensitivity or intermediate-term markers of glucose homeostasis, [7][8][9] leading some to question the role of GI, carbohydrate amount, and dietary carbohydrates in general in the development of diabetes. 6 However, because OmniCarb was conducted in people with intact regulatory systems for blood glucose, blood glucose may not have been sensitive enough to detect short-term dietary effects on glucose homeostasis.…”

Differential Ketogenic Diet-Induced Shift in CSF Lipid/Carbohydrate Metabolome of Pediatric Epilepsy Patients With Optimal Vs. No Anticonvulsant Response

“…Some carbohydrates were decreased, including glucose (significant in optimal responders) and the glycemic indicator 1,5-anhydroglucitol. [34] A number of hexoses and pentoses, however, were increased. Notably, sorbose and fructose were significantly increased only in patients with no clinical response.…”