Among the sustainable developmental goals (SDG), SDG 3.4 addresses Non-Communicable Diseases (NCDs) specifically, and world leaders committed to a one-third reduction in deaths between the ages 30 to 70 years from diabetes by the year 2030. Although the burden is worldwide, low- and middle-income countries (LMICs) are struggling with NCDs, with over three-quarters of all NCD deaths occurring in these countries. ¹ For instance, in Lebanon, 91% of all deaths are attributed to NCDs, ² and the initiatives, led by the Ministry of Public Health, to address the NCD burden failed to be implemented adequately. ^{3 – 5} This is due to the country’s political and economic challenges. ⁶ On the other hand, Lebanese patients with type 2 diabetes mellitus (T2DM) are experiencing medicine shortages, ⁷ which leads the patients to be incapable of buying their medical drugs. This deviation increased the health risk for these patients and increased the use and abuse of dietary supplements (DS). This increase may be due to several factors, including patients’ perceptions that DS’s natural products are safer, more effective, and cheaper than conventional medicines. ⁸ In Lebanon, there are no studies that investigate the prevalence of DS use and abuse among persons with T2DM or their knowledge, attitudes, and practices toward DS use. Our research group had already investigated DS use among children under 5 and their mothers, ⁹ among adults during the COVID-19 pandemic, ¹⁰ and among athletes. ¹¹ Thus, the aims of the current study are: (1) to estimate the prevalence of DS use among persons with T2DM amid the escalating economic crisis in Lebanon; (2) to explore the knowledge, attitude, and practice (KAP) of DS use; and (3) to determine any significant association between socio-economic and socio-demographic factors and the use of DS modality.

To the best of our knowledge, this is the first study that investigates the prevalence, and correlates of DS use among patients with T2DM during the economic crisis and drug shortage time in Lebanon. Almost 4 out of 10 patients with T2DM in our study were found to be using and abusing DS. Compared to the Unites states of America (USA), it was shown that 6 out of 10 Americans with T2DM use DS. ¹³ The prevalence reported in our study was higher than that reported in Saudi Arabia (17.6%), ¹⁴ Australia (24%), ¹⁵ and Thailand (5.3%) ¹⁶ but lower than the prevalence observed in Canada (44%), ¹⁷ and in 3 studies from the United States of America (USA) (62.1%; 67%; 58%). ^{18 – 20}

The most common DS used daily in the current study were multivitamins (27.6%), vitamin C (22.4%), followed by vitamin D (21.5%), iron (18%), and calcium (17.4%). These findings came hand in hand with the data reported in a Canadian study ¹⁷ (27.5% multivitamins, 18.9% vitamin E, 18.7% vitamin C, and 16% calcium), but it contradicts the results reported in Clifford et al., where in Australia vitamin C (18%) ranked first followed by garlic (17%), omega 3 (14%), vitamin E (13%) and multivitamins (12%). ¹⁵

According to the literature, the use of DS for diabetes management has always been reviewed from a pharmacy standpoint and from that of complementary and alternative medicine. ²¹ However, as supplement use continues to grow in Lebanon, ^{9 – 11} it is important for healthcare professionals to understand the evidence behind prescribing supplements and their potential role as part of medical care especially during the unstable conditions. For instance, according to the literature review, meta-analyses assessing the impact of vitamin C supplementation on diabetes-related outcomes assumed an improvement of fasting blood glucose only without any improvement in HbA1c in patients with T2DM. ^{22 – 24} In addition, three meta-analyses that examined folate or folic acid supplementation had conflicting findings. ^{25 – 27} As for B12 supplementation, many studies showed that individuals taking Metformin suffer from depleted serum B12 levels, and human studies on both B6 and biotin were extremely limited, with a lack of narrative reviews on both vitamins’ impact on T2DM patients. ²⁸ On the other hand, a meta-analysis that assessed the niacin supplementation showed an increased risk of T2DM onset following supplementation. ²⁹ As for vitamin D, a review conducted by Li et al. showed that most studies in patients with T2DM used vitamin D at 2000 IU/day, which may improve glycemic control and a dose of 4000 IU/day may be elicited to provide positive effects on HbA1c, HOMA-IR, and the fasting plasma glucose. ³⁰

The DS used by our study population was prescribed mainly by their physicians (70.2%). However, in the Arabian Gulf states, patients with T2DM did not reveal, discuss, or even seek medical advice from a physician, which differed from our findings, where participants relied heavily on physicians for DS advice. For instance, out of six studies conducted in the Gulf Club Countries (GCC), the majority of DS users did not tell their physicians about the use of DS. ^{14 , 31 – 35} Similarly, in Nigeria and the USA where the majority of DS among patients with T2DM were not being taken based on a recommendation from a health provider. ^{13 , 36}

Almost more than half of the participants in our study were satisfied with their DS use and intended to use it again (67.6%). Unlike Saudi Arabian participants with T2DM, where only 6.7% of respondents said they would use DS again, and 55.7% regretted its use. ¹⁴ In our study, 85% of the participants had heard of DS, some of them (67.4%) believed DS were safe, and more than half (63%) knew that DS are effective where 33.9% agreed that DS are necessary to control diabetes and 31% strongly agreed that DS prevent diabetic complications. These findings align with the data reported in an updated literature review that showed that patients usually expressed the attitude that DS may not help much but will not hurt. ³⁷ Additionally, our participants’ main reason for utilizing DS in this study was to lower their blood sugar level (56.1%), followed by improving overall health (35.5%). Thus, a responsible healthcare approach is much needed for the patients to receive evidence-based DS information about efficacy, effectiveness, adverse effects, and possible interactions. A slight majority (57.2%) of participants supported the use of DS in conjunction with their medical treatment for T2DM. This finding aligns with the result observed in a Saudi Arabian and Nigerian study where 90% and 67% of the patients with T2DM preferred combining DS with their conventional therapies, respectively. ^{14 , 36}

In a qualitative study in Pakistan, the principal motivator of DS use was the desire to cure T2DM, where 41% preferred combining DS and T2DM. ³⁸

In our study, the level of education, the frequency of monitoring blood sugars, and reading labels can mediate the use of DS. On contrary, the predictors of DS use in Saudi Arabia were age above 51 years, unemployment, and the participants’ knowledge about the effectiveness of complementary and alternative medicine (CAM) products. ¹⁴ Moreover, in Thailand, female gender, age 40-69 years, and diabetes duration of less than 10 years were significant correlators of DS use. ³⁹ A Chinese study found that DS use among people with T2DM was associated with a history of previous DS use for other conditions, a positive attitude towards DS, efficacy of DS, and a longer duration of diabetes. ⁴⁰

Moreover, a study from Malaysia found that females were 1.8 times more likely to use DS than males. ⁴¹ Furthermore, a study from Bahrain showed that females DS users were more likely to be dominating, and those who have had diabetes for a longer time and have T2DM complications were the top users. ⁴² Another study from Saudi Arabia showed that the most common users of DS practices were older females, housewives, and illiterates. ⁴³

This study presents some limitations. First, it lacks the impact of DS on T2DM compared to conventional therapy. Second, a self-reported questionnaire was used for most of the reported measures. Thus, bias may be present due to inaccurate self-reporting and memory in some questions. Third, this study was of cross-sectional survey; therefore, only associations can be determined and not causations. Notably, the strength of this study is that it is the first study that has been carried out in Lebanon which brought up the topic of knowledge, attitudes, and practices to DS use among patients with T2DM.

This study estimated the prevalence of DS use and abuse among patients with T2DM during the time of medicine shortage and economic crisis. Public health experts should encourage healthy discussions with their patients to comprehend their views regarding DS use. In addition, clinicians and researchers should collaborate to initiate safety and efficacy trials on common DS used for diabetes. Accordingly, relevant institutions whether governmental and non-governmental organizations, are strongly asked to design awareness programs that will be addressed to target groups and implemented by a specialized team in which social workers and health promoters play an important role by developing materials which fit all the perception of all categories that were shown by the study, and especially suitable to those who are illiterate, and who cannot read labels. The presence of evidence-based studies in the form of randomized controlled trials will help both patients and clinicians regarding the use of a DS product.

The study was approved by the ethical committee of al Zahraa University Medical Center (#157/May 7, 2022). Written informed consent was obtained from all subjects involved in the study. Written informed consent was obtained also from the patient(s) to publish this paper.

MA, RM and MH conceived the idea, designed the study, helped in collecting the data, analyzed the data, drafted and reviewed the manuscript. SD helped in collecting the data, reviewed and edited the manuscript. NA and MS collected and analyzed the data. All authors read and approved the final manuscript.