Purpose: Multiple trials in the past have shown conflicting results of whether cinnamon lowers glucose or hemoglobin A1C (HbA1C). The purpose of this study was to determine whether cinnamon lowers HbA1C in patients with type 2 diabetes. I performed a randomized, controlled trial to evaluate whether daily cinnamon plus usual care versus usual care alone lowers HbA1c.Methods: I randomized 109 type 2 diabetics (HbA1C >7.0) from 3 primary care clinics caring for pediatric, adult, and geriatric patients at a United States military base. Participants were randomly allocated to either usual care with management changes by their primary care physician or usual care with management changes plus cinnamon capsules, 1g daily for 90 days. HbA1c was drawn at baseline and 90 days and compared with intention-to-treat analysis. This study was approved by an institutional review board.Results As the worldwide incidence of diabetes increases, the search for dietary adjuncts to treat this lifealtering disease has become far ranging. Cinnamon is purported to be a natural insulin sensitizer, with adverse events of perioral dermatitis and stomatitis reported uncommonly with high intake.1 Both in vitro and in vivo animal studies have shown that cinnamon is an insulin sensitizer. found that polyphenols from cinnamon inhibit the formation of advanced glycation end products in bovine serum albumin. To date, 5 randomized trials studying cinnamon in humans with type 2 diabetes have been published, with conflicting results. 6 -10 The results of these studies are mixed, and it is unclear whether any of them were conducted among primary care populations. Two of these studies showed a possible effect of cinnamon on fasting serum glucose, but they did not examine hemoglobin A1C (HbA1C) levels. One study showed no effect on plasma glucose. Two studies-one each done with patients with type 1 and type 2 diabetes-showed no effect of cinnamon on HbA1C (Table 1). A meta-analysis of these studies in divergent populations measuring different parameters showed no effect of cinnamon on HbA1C, glucose, or lipids. 11This trial strove to replicate the conditions found in primary care, where patients often have medication changes, comorbid conditions, and dietary changes. As such, it was not an efficacy trial with every variable controlled. It attempted to determine whether the intervention of taking cinnamon lowers HbA1C. Effectiveness trials such as this are critical in determining if the interventions This article was externally peer reviewed.

Supplemental O2 reduces cardiac output and raises systemic vascular resistance in congestive heart failure. In this study, 100% O2 was given to normal subjects and peak forearm flow was measured. In experiment 1, 100% O2 reduced blood flow and increased resistance after 10 min of forearm ischemia (flow 56.7 +/- 7.9 vs. 47.8 +/- 6.7 ml.min-1.100 ml-1; P < 0.02; vascular resistance 1.7 +/- 0.2 vs. 2.4 +/- 0.4 mmHg.min.100 ml.ml-1; P < 0.03). In experiment 2, lower body negative pressure (LBNP; -30 mmHg) and venous congestion (VC) simulated the high sympathetic tone and edema of congestive heart failure. Postischemic forearm flow and resistance were measured under four conditions: room air breathing (RA); LBNP+RA; RA+LBNP+VC; and 100% O2+LBNP+VC. LBNP and VC did not lower peak flow. However, O2 raised minimal resistance (2.3 +/- 0.4 RA; 2.8 +/- 0.5 O2+LBNP+VC, P < 0.04). When O2 alone (experiment 1) was compared with O2+LBNP+VC (experiment 2), no effect of LBNP+VC on peak flow or minimum resistance was noted, although the return rate of flow and resistance toward baseline was increased. O2 reduces peak forearm flow even in the presence of LBNP and VC.

This article provides an introduction and background to the review, summarizes the methodological processes involved, details the initial results, and identifies strengths and weakness of the review. Specific results of the review as well as overall recommendations for moving this field of research forward are detailed throughout the current Pain Medicine supplement.