title: A single dose of sodium nitrate does not improve oral glucose tolerance in patients with type 2 diabetes mellitus.
abstract: Dietary nitrate (NO3(-)) supplementation has been proposed as an emerging treatment strategy for type 2 diabetes. We hypothesized that ingestion of a single bolus of dietary NO3(-) ingestion improves oral glucose tolerance in patients with type 2 diabetes. Seventeen men with type 2 diabetes (glycated hemoglobin, 7.3% ± 0.2%) participated in a randomized crossover experiment. The subjects ingested a glucose beverage 2.5 hours after consumption of either sodium NO3(-) (0.15 mmol NaNO3(-) · kg(-1)) or a placebo solution. Venous blood samples were collected before ingestion of the glucose beverage and every 30 minutes thereafter during a 2-hour period to assess postprandial plasma glucose and insulin concentrations. The results show that plasma NO3(-) and nitrite levels were increased after NaNO3(-) as opposed to placebo ingestion (treatment-effect, P = .001). Despite the elevated plasma NO3(-) and nitrite levels, ingestion of NaNO3(-) did not attenuate the postprandial rise in plasma glucose and insulin concentrations (time × treatment interaction, P = .41 for glucose, P = .93 for insulin). Despite the lack of effect on oral glucose tolerance, basal plasma glucose concentrations measured 2.5 hours after NaNO3(-) ingestion were lower when compared with the placebo treatment (7.5 ± 0.4 vs 8.3 ± 0.4 mmol/L, respectively; P = .04). We conclude that ingestion of a single dose of dietary NO3(-) does not improve subsequent oral glucose tolerance in patients with type 2 diabetes.
authors.affiliation: Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands; Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Naomi M
authors.initials: NM
authors.lastname: Cermak
authors.affiliation: Faculty of Medicine and Life Sciences, Hasselt University, Diepenbeek, Belgium; Heart Centre Hasselt, Jessa Hospital, Hasselt, Belgium.
authors.forename: Dominique
authors.initials: D
authors.lastname: Hansen
authors.affiliation: Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands.
authors.forename: Imre W K
authors.initials: IW
authors.lastname: Kouw
authors.affiliation: Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands; Institute of Sport and Exercise Studies, HAN University of Applied Sciences, Nijmegen, The Netherlands.
authors.forename: Jan-Willem
authors.initials: JW
authors.lastname: van Dijk
authors.affiliation: Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom.
authors.forename: Jamie R
authors.initials: JR
authors.lastname: Blackwell
authors.affiliation: Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Jones
authors.affiliation: Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Gibala
authors.affiliation: Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands. Electronic address: L.vanLoon@maastrichtuniversity.nl.
authors.forename: Luc J C
authors.initials: LJ
authors.lastname: van Loon
mesh_terms: D000368:Aged; D001628:Beverages / Q000032:analysis; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D015992:Body Mass Index; D018592:Cross-Over Studies; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy*; D004032:Diet; D004311:Double-Blind Method; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D009566:Nitrates / Q000008:administration & dosage*; D019518:Postprandial Period
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007328:Insulin; D009566:Nitrates; C031618:sodium nitrate
keywords: Blood glucose; Crossover studies; Hyperglycemia; Insulin; Nitrates; Nitrites