Effects of High-Dose Resveratrol in Non-Diabetic Obese Males
Condition: Obesity; Diabetes
MeSH terms: Obesity
Study type: Interventional
Phase: Phase 2

Summary: 
      The primary aim of our study was to examine the effects of two weeks of oral resveratrol on
      resting energy expenditure and insulin sensitivity in non-diabetic obese male subjects.
      Secondary variables included plasma lipid subfraction, blood pressure and glycated hemoglobin
      (HbA1c).
    

Detailed description: 
      Patients were recruited between July 2009 and July 2012 from a single hospital in Singapore.
      Eligible patients were Chinese males, aged between 21 and 55 years old, with a body mass
      index (BMI) of 30 kg/m2 or more and venous glucose of <7.0 and <11.1 mmol/L at 0 and 120
      minutes respectively on oral glucose tolerance testing (OGTT) following a 12-hour fast. They
      must be willing to abstain from embarking on an exercise regime or ingesting large quantities
      of resveratrol-containing foods including alcohol during the study period.

      The study was a randomized, double-blind, parallel group trial consisting of a screening
      visit, a two-week treatment period and a post-treatment visit.

      Randomization was centrally performed during treatment assignment with a 2-digit reference
      code placed in sealed opaque envelopes maintained by the person responsible for the
      preparation of the intervention drug and placebo. Trans-resveratrol extract from Polygonum
      Cuspidatum (Mega Resveratrol, Danbury, USA) was used in the trial. The placebo was not
      distinguishable by color, form, or taste from the active drug. The randomization code was
      unblinded only after all predefined data were recorded.

      Subjects were given 1g three times a day of either resveratrol or placebo for two weeks and
      instructed to abstain from foods with high resveratrol content during the entire duration of
      the trial. Compliance was determined by pill counting at the end of the trial period.
      Subjects in both arms were not allowed to commence on an exercise regimen or supplements
      during the study period. Subjects who dropped out of the trial would not be replaced. All
      variables were measured at baseline and at the end of the treatment period.

      RMR was measured by indirect calorimetry using a breath-by-breath metabolic gas analyser via
      the face-mask method.

      The investigators estimated that a sample size of 18 patients per group (Total N = 36) was
      needed to provide 80% power and two-sided 5% to detect a difference in a Cohen's effect size
      of 1.0 between the two groups.

      All analyses were performed using SPSS 21.0 (IBM) with statistical significance set at p <
      0.05 and with the percentage change from baseline as the unit of analysis. All data were
      analyzed according to the intention-to-treat principle. MANOVA was performed to compare the
      intervention and placebo groups for the unadjusted and adjusted p-values on the study
      variables of interest. Normal distribution was verified with the Kolmogorov-Smirnov test and
      data were presented as mean ± standard deviation (SD).
    

Intervention name(s): Resveratrol; Placebo
Intervention type(s): Drug; Drug
Intervention description(s): 1g tds 2 weeks; Sugar pill 1g tds for 2 weeks
Other intervention name(s): Mega Resveratrol
Intervention MeSH terms: Resveratrol
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Treatment
Keywords: Resveratrol; obesity; insulin resistance; energy expenditure; diabetes