Review finds honey improves cardiometabolic risk factors

2nd December 2022

A systematic review suggests that eating honey may improve both lipid and glycaemic health markers when consumed as part of a healthy diet

Consumption of honey appears to improve cardiometabolic risk factors through favourable changes in glycaemic control and lipid levels according to a systematic review and meta-analysis by Canadian researchers.

Honey is a natural product formed from the nectar of flowers by honeybees and has a long history of use for both nutritional needs and its medicinal properties. Nevertheless, honey contains free sugars, and the World Health Organisation has called for adults and children to reduce their daily intake of free sugars to less than 10% of their total energy intake and have included honey as a source of free sugars. Despite the presence of free sugars, honey also contains flavonoids and phenolic acids which have a positive impact on health, through antioxidant and anti-inflammatory properties. These effects had led to the widespread use for the treatment of eye diseases, bronchial asthma, throat infections, tuberculosis, thirst, hiccups, fatigue, dizziness, hepatitis, and wounds, as well as being taken as a supplement.

Although excessive intake of free sugars is linked to higher rates of obesity, the cardiometabolic effects of honey intake have not been systematically explored and was the subject of the present study by the Canadian researchers. The team searched for both randomised and non-randomised controlled feeding studies that examined the effect of oral honey intake on adiposity, glycaemic control and lipid levels. The researchers measured the mean differences (MD) between participants assigned to honey and control arms.

Honey intake and cardiometabolic risk

A total of 18 controlled feeding trials in 1105 participants with a median age of 41.2 years (54% female) and which considered 33 different comparisons were identified and included in the analysis.

The researchers identified a significant reduction in total cholesterol (MD = -0.18 mmol/L, p = 0.011), LDL cholesterol (MD = -0.30 mmol/L, p = 0.0024) and an increase in HDL cholesterol (MD = 0.07 mmol/L, p < 0.001).

In addition, oral honey reduced fasting glucose (MD = -0.20 mmol/L, p = 0.017). However, there was also an increase of interleukin-6 (IL-6) levels (MD = 0.37 pg/ml, p = 0.046) and tumour necrosis factor alpha (MD = 1.44 pg/ml, p = 0.019). The reasons for an increase in IL-6 levels is unclear but some data points to how release of the cytokine from the contracting skeletal muscle is perhaps one of the molecular signals promoting the beneficial effects of exercise.

There were also differences based on the floral source and by processing, with robinia, clover and raw honey more beneficial than the processed form.

Summarising the benefits, the authors state that a median intake of 40 g of honey for 8 weeks appears to be sufficient to deliver the cardiometabolic benefits. Nevertheless, despite these positive findings, the authors did identify that much of the evidence was of low certainty and called for more studies focusing on the floral source and the processing of honey to increase the certainty of this evidence.

Citation
Ahmed A et al. Effect of honey on cardiometabolic risk factors: a systematic review and meta-analysis. Nutr Rev 2022

CGM associated with better control in type 2 diabetics receiving basal insulin

14th June 2021

Whether continuous glucose monitoring improves outcomes for type 2 diabetics compared with self-testing is uncertain.

The monitoring of blood glucose is paramount to the safe and effective management of all diabetic patients. Typically, insulin regimes can be basal only (i.e. long-acting agents used once or twice daily) or a combination of basal and prandial, i.e., rapid-acting agents used to control the mead-induced glucose spikes.

Moreover, assessment of blood glucose levels is achieved through the use of either testing strips or real-time continuous glucose monitoring (CGM). However, in practice, self-testing has been shown to be under-utilised and while the latter has been shown to improve diabetic control in type 2 diabetes using a combined insulin regime, little is known about the effectiveness of CGM in patients with less intensive insulin regimes.

Therefore, a team of researchers from the International Diabetes Centre, Minneapolis, US, performed a randomised controlled trial to determine the effectiveness of CGM in primary care adults with type 2 diabetes using only basal insulin compared with the use of traditional blood glucose monitoring (BGM).

Included patients had a baseline HbA1c level of 7.8% to 11.5%, self-reported BGM monitoring of at least 3 or more times per week and possession of a smartphone compatible with the CGM device for uploading data. The primary outcome measure was the HbA1c level after 8 months and key secondary outcomes were CGM-measured time in the target glucose range (70–180mg/dl) and the time with glucose levels above 250mg/dl.

Findings

A total of 175 participants with a mean age of 57 years (50% women) and with a mean HbA1c level of 9.1% were randomised in a 2:1 fashion to CGM or BGM. After eight months, the mean HbA1c reduced to 8.0% in the CGM group and to 8.4% in the BGM group (p = 0.02). In the GCM group, the mean percentage of time in the target glucose range was 59% compared to 43% in the BGM group (p < 0.001). Similarly, there was a significantly lower time where glucose levels exceeded 250mg/dl (11% vs 27%, CGM vs BMG, p < 0.01).

In discussing their findings, the authors noted that the greater improvements seen in HbA1c in the CGM group were due to an increased period of time for which glucose levels remained with the target range. Nevertheless, a limitation recognised by the authors was the use of diabetic specialists, which is not standard practice in primary care and that this may have limited the generalisability of their findings. Despite this, they concluded that the use of CGM resulted in superior diabetic control compared with self-monitoring.

Citation

Martens T et al. Effect of Continuous Glucose Monitoring on Glycemic Control in Patients with Type 2 Diabetes Treated with Basal Insulin. A Randomised Clinical Trial JAMA 2021