Background: Dietary supplement use has not been studied well in non-Western societies. There have been no surveys on the prevalence of dietary supplement use among professionals, in particular, ophthalmologists, and is unknown to what extent ophthalmologists recommend dietary supplements to their dry eye patients.
Methods: A survey questionnaire was administered online and per mail in February 2017 to approximately 600 ophthalmologist members of the Dry Eye Society, Japan. The ophthalmologists were asked questions on their personal use of dietary supplements and whether they recommended dietary supplements to their patients.
Results: The 196 ophthalmologists who responded to this survey were aged between 28 and 77 years (mean age, 50.2 ± 10.1 years) and 59.2% were women. A total of 67.9% recommended supplements to their patients; the main target diseases were age-related macular degeneration (97.0%) and dry eye (45.9%). For dry eye, the three most commonly cited reasons for recommending supplements in practice included, 1) expectation of a positive effect, 2) requests by patients, and 3) availability of a product manufactured by a reputable company. The three most commonly recommended components included lactoferrin, the omega-3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), and lactic acid bacterium. The ophthalmologists who reported not recommending dietary supplements cited lack of evidence (54.8%), lack of information on which supplements to recommend to patients (38.5%), and high cost (increasing the patients' out of pocket charges) (35.6%) as their main reasons. Regarding their own approach to a healthy diet and lifestyle, almost all ophthalmologists reported adopting a healthy lifestyle such as exercising, positive thinking, and implementing dietary restrictions. A total of 62.2% stated currently using dietary supplements. Those who reported not using any supplements cited sufficient evidence as the main prerequisite to consider using them (75.7%).
Conclusion: The majority of ophthalmologists in this study recommended dietary supplements to their dry eye patients following to macular degeneration patients. Many also reported using dietary supplements regularly as part of their own approach to a healthy diet and lifestyle. More evidence and data on their effectiveness and side effects on dietary supplements should be required for their appropriate and safe use.
Motoko Kawashima, Miki Uchino, Sachiko Inoue, Norihiko Yokoi, Kazuo Tsubota