In their recent publication, K hanal et al. promote the topical use of honey in the oral mucosa of patients undergoing head and neck radiotherapy (HNR). We have some concerns about this recommendation.

Remarkably, oral side effects from HNR tend to occur simultaneously and patients often experience mucositis, hipossalivation, taste changes, fungal infections, oral pain and radiation-related caries RRC concurrently. The impact of clustering of oral complications must be taken in consideration during the management of these patients in order to improve supportive care and patient’s quality of life . In this regard, dietary counselling is one of the cornerstones and is mainly based in sugar and other fermentable carbohydrates restriction, avoiding sticky foodstuffs with low oral clearance (such as honey) and avoiding drug preparations containing sugar .

RRC, also known as “radiation caries”, affects patients who underwent HNR and is currently accepted as a complex and multifactorial disease. It is mainly regarded as a consequence of indirect effects of radiation such as hipossalivation, shifts in oral microflora and altered saliva composition. In addition, oral mucositis and other oral side effects increase the risk of caries because they impair oral hygiene due to the associated pain, leading to an increase intake of soft, carbohydrate-rich and more cariogenic foods . RRC has a high potential of teeth destruction and its rapid onset and progression often leads to extensive loss of dentition within short periods of time, causing a negative impact in quality of life. Also, it is still posing as a challenge for dentistry due to high rates of recurrent caries and a reduction of restoration longevity due to recurrent restorations failure and deterioration that tends to occur rapidly .

Contemporary recommendations for RRC prevention includes dietary counselling, adequate plaque control, oral healthcare before, during, and after HNR and daily use of fluoride products without mucosa irritating components . In this context, our concern is that the topical use of honey, three time a day, in the oral mucosa of patients with low motivation for oral hygiene, and already exposed to a high risk for rampant caries could act in synergy with the other above mentioned risk factors and turn the risk for RRC development even higher.

Major ingredients of honey are glucose, fructose and sucrose. Gluconic is the major acid found in honey; acetic, lactic, butyric, and formic acid are also present, all of which could contribute to the cariogenic properties of honey . Direct studies to explore the cariogenic potential of honey are contradicting and although honey has been promoted to be less cariogenic in dry-mouth subjects by a single in situ and uncontrolled study, further evidence to support this hypothesis is needed .

In summary, honey can be highly cariogenic and certainly should be avoided in patients undergoing HNR. If there are no alternatives, future studies or protocols of mucositis prevention and treatment based on honey preparations should, at least, provide clear information to the patients that they must rinse their mouth with water each time honey is used and also perform careful mechanical cleaning by brushing their teeth in order to avoid the development of RRC. Finally, future studies regarding the efficacy of honey in the prevention of radiation-related oral mucositis should provide detailed oral health and dental status information obtained from long term follow-up of patients enrolled. Most importantly, randomized, controlled clinical trials must be carried out to compare the incidence of RRC in cancer patients receiving honey for the prevention of oral mucositis.

Sincerely,