Inadequate Vitamin C Status in Prediabetes and Type 2 Diabetes Mellitus: Associations with Glycaemic Control, Obesity, and Smoking

• Published in: Nutrients 2017-09, Vol.9 (9), p.997
• Main Authors: Wilson, Renée, Willis, Jinny, Gearry, Richard, Skidmore, Paula, Fleming, Elizabeth, Frampton, Chris, Carr, Anitra
• Format: Article
• Language: English
• Subjects: Adult; Adults; Aged; Anthropometry; Ascorbic acid; Ascorbic Acid - administration & dosage; Ascorbic Acid - blood; Ascorbic Acid Deficiency - blood; Ascorbic Acid Deficiency - complications; Blood Glucose - metabolism; Body mass; Body Mass Index; Body Weight; C-reactive protein; C-Reactive Protein - metabolism; Complications; Cross-Sectional Studies; Demographics; Diabetes; Diabetes mellitus; Diabetes Mellitus, Type 2 - blood; Diabetes Mellitus, Type 2 - complications; Diabetes Mellitus, Type 2 - drug therapy; Exercise; Female; Gastrointestinal Microbiome; Glucose; Glucose tolerance; glycaemic control; Glycated Hemoglobin - metabolism; Humans; Male; metabolic health; Metformin; Metformin - therapeutic use; Middle Aged; Nutrient deficiency; Obesity; Obesity - blood; Obesity - complications; Physical activity; Pilot Projects; Plasma; Plasmas (physics); prediabetes; Prediabetic State - blood; Prediabetic State - complications; Prediabetic State - drug therapy; Risk reduction; Sensitivity analysis; Smoking; Smoking - adverse effects; Smoking - blood; type 2 diabetes mellitus; Vitamin C; Waist Circumference
• ISSN: 2072-6643; 2072-6643
• DOI: 10.3390/nu9090997

Vitamin C (ascorbate) is an essential micronutrient in humans, being required for a number of important biological functions via acting as an enzymatic cofactor and reducing agent. There is some evidence to suggest that people with type 2 diabetes mellitus (T2DM) have lower plasma vitamin C concentrations compared to those with normal glucose tolerance (NGT). The aim of this study was to investigate plasma vitamin C concentrations across the glycaemic spectrum and to explore correlations with indices of metabolic health. This is a cross-sectional observational pilot study in adults across the glycaemic spectrum from NGT to T2DM. Demographic and anthropometric data along with information on physical activity were collected and participants were asked to complete a four-day weighed food diary. Venous blood samples were collected and glycaemic indices, plasma vitamin C concentrations, hormone tests, lipid profiles, and high-sensitivity C-reactive protein (hs-CRP) were analysed. A total of 89 participants completed the study, including individuals with NGT ( = 35), prediabetes ( = 25), and T2DM managed by diet alone or on a regimen of Metformin only ( = 29). Plasma vitamin C concentrations were significantly lower in individuals with T2DM compared to those with NGT (41.2 µmol/L versus 57.4 µmol/L, < 0.05) and a higher proportion of vitamin C deficiency (i.e.