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| Date: 07-31-2015 | HC# 071561-525 |
Re: Kanuka Honey Formulated with Cinnamon, Chromium, and Magnesium Improves Blood Lipids and Weight, but not Glycemic Parameters, in Patients with Type 2 Diabetes
Whitfield P, Parry-Strong A, Walsh E, Weatherall M, Krebs JD. The effect of a cinnamon-, chromium- and magnesium-formulated honey on glycaemic control, weight loss and lipid parameters in type 2 diabetes: an open-label cross-over randomised controlled trial. Eur J Nutr. May 19, 2015; [epub ahead of print]. doi: 10.1007/s00394-015-0926-x.
Type 2 diabetes affects many throughout the world and can lead to mortal health consequences. Honey has a history of medicinal uses in many traditional medicinal systems, and recent work has suggested its use as a sweetener for those with diabetes due to a potentially lower glycemic index. Additionally, recent work suggests that cinnamon (Cinnamomum spp., Lauraceae) bark, along with chromium and magnesium, may increase insulin sensitivity. This open-label, randomized, crossover trial investigated the effects of kanuka (Kunzea ericoides, Myrtaceae) honey containing cinnamon, chromium, and magnesium in comparison with the honey alone. Changes in glucose metabolism, glycemic control, and lipid profile were assessed in both male and female patients with type 2 diabetes.
This study took place at the Centre for Endocrine, Diabetes and Obesity Research at Wellington Regional Hospital, Wellington, New Zealand. Included patients had type 2 diabetes and were taking metformin. The use of sulphonylurea, insulin, or therapeutics targeting glucose tolerance was not allowed. Also, those with glycosylated hemoglobin (HbA1c) >80 mmol/mol or 9.5% were excluded, but prior cinnamon, chromium, or magnesium supplementation was allowed with a mandatory washout period of 20 days before the study.
Patients consumed 3 tbsp daily of either control (53.5 g/day kanuka honey) or treatment (53.5 g/day kanuka honey containing 4.5 g cinnamon, 200 µg chromium polynicotinate, and 120 mg magnesium citrate) for 40 days in random order. Kanuka honey was supplied by HoneyLab Ltd; Wellington, New Zealand. No other details about the source or processing of cinnamon (species not identified), chromium, or magnesium were given. Study administrators, but not patients, were blinded.
Two experiments were conducted. In the first, an acute study, fasting blood samples were taken and either honey control or treatment was administered on 2 pieces of "wholemeal" bread (70.4 g total carbohydrate). Blood samples were collected every 30 minutes up to 120 minutes. The Matsuda index was used to gauge insulin sensitivity, and areas under the curve were analyzed. Secondly, a long-term experiment was carried out. Patients took 53.5 g of honey for 40 days with measurements taken at baseline and endpoint. Empty honey containers were used to gauge compliance, and food consumption was measured 3 days before baseline and endpoint visits. Between control and treatment regimens, a 20-day washout period was completed.
In total, from 30 potential patients, 12 were enrolled (average age was 61.7 years) that had type 2 diabetes for an average of 5.4 years. Compliance averaged 85% for the control and 86% for the treatment. One patient did not participate in the second part of the study due to decreased glycemic control and was analyzed in the intention-to-treat population. Following the acute experiment, no differences were seen between control or treatment honey preparations for Matsuda indices or glucose or insulin areas under the curve.
After the long-term treatment, the change from baseline to endpoint in fasting glucose approached significance (P=0.06) between honey preparations (control=7.5 ± 1.9 mmol/L vs. 8.2 ± 2.2 mmol/L, treatment=8.2 ± 3.4 mmol/L vs. 7.2 ± 1.8 mmol/L). The increase in sugar intake following the 40-day treatment period approached significance for the control (P=0.09) and treatment (P=0.08). Also, following the treatment honey ingestion, both the total cholesterol and low-density lipoprotein (LDL) cholesterol of patients were decreased significantly more than after consumption of the control honey (total cholesterol=−0.37 mmol/L, 95% confidence intervals [CI]: −0.073, −0.008, P=0.046; LDL cholesterol=−0.29 mmol/L, 95% CI: −0.57, −0.23, P=0.039). High-density lipoprotein cholesterol also increased nonsignificantly after consumption of the treatment honey. Lastly, patient weight significantly decreased by 2.2 kg after consumption of the treatment honey (95% CI: −4.2, −0.1, P=0.039).
In summary, consumption of kanuka honey together with cinnamon, chromium, and magnesium significantly decreased total and LDL cholesterol and weight, while having no significant effect on glucose, insulin, or insulin sensitivity. Discussed weaknesses include the short duration of the 40-day study, potentially small dosage, and lack of regimentation of daily consumption. This combination honey treatment may be of use in lipid modulation in type 2 diabetes sufferers; however, this study does not suggest its use for glucose metabolism or insulin sensitivity. Also, the nonsignificant sugar intake increase associated with the consumption of both the control and treatment honey should be closely monitored in patients with type 2 diabetes consuming this honey.
This study was funded by HoneyLab Ltd.
—Amy C. Keller, PhD 