Ascorbic acid supplementation improves postprandial glycaemic control and blood pressure in people with type 2 diabetes: Findings of a randomized cross-over trial.
Diabetes Obes Metab. 2018 Nov 4. Epub 2018 Nov 4. PMID: 30394006
Shaun A Mason
AIMS: The primary aim of the study was to investigate whether ascorbic acid (AA) supplementation improves postprandial glucose responses under free living conditions in people with type 2 diabetes. A secondary aim was to investigate the effect of AA supplementation on blood pressure.
MATERIALS AND METHODS: Thirty-one people with type 2 diabetes (26 males/5 females; aged 61.8±6.8 y; duration of diabetes 5.6±4.6 y; HbA1c 7.6±0.7% [mean±SD]) were enrolled in a randomized cross-over study involving 4 months of supplementation with oral AA (2x500 mg/day) and placebo. Participants wore continuous glucose monitors for 48 h and consumed standardized meals pre- and post-supplementation. Measurements included postprandial glucose incremental areas under the curve (iAUC), duration of day in hyper- and hypo-glycaemia, average 24 h and daily postprandial glucose concentrations, HbA, insulin, blood pressure and oxidative stress (F-isoprostanes).
RESULTS: Following AA supplementation, significant decreases were observed for daily postprandial glucose iAUC (-36%), duration of day in hyperglycaemia (-2.8 h/day) and postprandial hyperglycaemia (-1.7 h/day), average 24 h glucose (-0.8 mmol/L) and daily postprandial glucose (-1.1 mmol/L) concentrations, systolic (-7 mmHg) and diastolic (-5 mmHg) blood pressures, and a specific fraction of free plasma F-isoprostanes (-47 pg/ml), when compared to placebo.
CONCLUSIONS: People with type 2 diabetes experienced improved postprandial and 24 h glycaemia and decreased blood pressure after 4 months of AA supplementation when compared to placebo. These findings offer evidence for the proposed use of AA as an adjunct therapy to improve glycaemic and blood pressure control in people with type 2 diabetes (#ACTRN12616000276459). This article is protected by copyright. All rights reserved.