Vitamin-D deficiency is a major global public health issue. Globally, over 1 billion individuals suffer from Vitamin-D deficiency, defined as serum 25(OH)D levels below 20 ng/mL [1]. Vitamin-D, a member of the steroid hormone group, is a fat-soluble vitamin. It must be dissolved in dietary fat and emulsified by bile salts before absorption [1,2]. It plays an important role in preserving bone health and calcium balance and in the regulation of immune function, inflammation and cellular growth [3].   There two forms of Vitamin-D that later on converted into active form in our body (1.25 dihydroxy Vitamin-D): Ergocalciferol (Vitamin-D2), taken from plants and Cholecalciferol (Vitamin-D3), obtained from animal-supplied meals. However, sun exposure is by far the most essential source of Vitamin-D3, accounting for 90% of the total amount [1,3]. Nowadays, Vitamin-D is one of major interesting topics being discussed in research and clinics, as well as among individuals concerned with their health [3,4].   Maintaining sufficient Vitamin-D levels is an important factor in preventing osteoporosis as well as osteomalacia in adults and rickets in children. Studies are now uncovering its significance in overall health and chronic disease prevention [4]. Although the importance of Vitamin-D has already been established, Vitamin-D deficiency, defined as a serum 25(OH)D concentration below 20 ng/mL, remains a worldwide health issue [5]. In most European countries, there is a prevalent issue in reaching normal Vitamin-D levels [6]. Except for countries with high fish intake and Vitamin-D supplementation, such as Finland [7,8].   In Saudi Arabia, despite the year-round availability of abundant sunlight, a high prevalence of Vitamin-D deficiency has been documented among people of all ages and genders, with studies estimating the prevalence to be as high as 60%-97% particularly higher levels in females, children and young adults [8]. An analytical cross-sectional study was conducted among the residents of Al-Qunfudhah governorate in Saudi Arabia. A total of 466 individuals participated in this study. Although 91% of them had previously heard of Vitamin-D, only 17.4% could identify sunlight exposure as the primary source of Vitamin-D [9]. Another study employed a self-administered online survey to gather information on the characteristics, knowledge, attitudes and self-reported behaviors of 800 Saudi Arabian mothers regarding Vitamin-D deficiency. The findings revealed that more than half of the mothers had a limited understanding. Less than two-thirds of the participants recognized their inadequate practice of taking Vitamin-D rich foods. Furthermore, two-thirds of the mothers displayed a negative attitude towards Vitamin-D deficiency [10].   A retrospective study was conducted involving patients who visited the outpatient clinics at Alameen General Hospital, Taif (Saudi Arabia) between 2019 and 2021. Demographic, clinical and laboratory data were gathered using a hospital software system. The study encompassed 2153 patients and among them, 900 individuals (41.8%) were found to have Vitamin-D deficiency [11].   A cross-sectional study was conducted in the Qassim Region of Saudi Arabia, utilizing a convenient non-probability sampling method with a sample size of 375 participants [12]. The findings indicate that while most individuals possess some knowledge about Vitamin-D, there are notable deficiencies in awareness of Vitamin-D deficiency among adults in Qassim, Saudi Arabia. Factors such as education, living in urban areas, employment status and income level were significant in determining awareness, highlighting the importance of targeted educational efforts. It is essential to disseminate information about Vitamin-D and its various aspects through different media channels, including television and social media platforms [13].   Deficiency of Vitamin-D can result in multiple other health serious consequences such as depression, fatigue, hyperparathyroidism, obesity, osteomalacia, chronic backache, hypertension, cancer, chronic pain, diabetes, multiple sclerosis and heart disease [14]. Vitamin-D is of great importance for multiple physiological and biological human processes. It is a common misconception that Vitamin-D deficiency mostly affects the elderly or those in medical care. Nonetheless, research indicates that younger adults are more prone to having low level of Vitamin-D. Besides its well-documented role in regulating calcium balance and enhancing bone mineralization, it has been reported that Vitamin-D has an impact on human reproductive system health [15].   Research conducted in Saudi Arabia has shown that almost half of participants generally had a limited understanding of the normal levels of Vitamin-D and 30% of participants don’t know the recommended daily intake [10,12,15]. A majority were not aware of its benefits for vision, muscle health, weakness and fatigue [16]. Only 43.1% recognized that a reduced intake of Vitamin-D- rich foods contributes to deficiency. About 33.7% of participants preferred sun exposure to boost their Vitamin-D levels, while 32.4% opted for supplements [17]. However, just 39.2% had ever checked their Vitamin-D status [15-17].   A five-year retrospective study (2017-2021) involving 22.335 individuals from Majmaah found a 67.3% prevalence of Vitamin-D deficiency [18]. A study among elderly patients (above 60 years old) attending primary care centers in Jeddah reported a 60.8% Vitamin-D deficiency with 29.9% insufficiency [19].   Vitamin-D deficiency remains a major public health concern in Saudi Arabia even though Saudi Arabia is an area rich in sunlight. This contributes to increased risk of diseases related to Vitamin-D deficiency. Complications of Vitamin-D deficiency in Saudi Arabia can be minimized by building awareness on various sources of Vitamin-D. Previous studies done in Hail, have reported Vitamin-D deficiency among all age groups [4,11]. The incidence of Vitamin-D is increasing every year [13] hence present study is conducted to assess awareness and preventive practices regarding Vitamin-D deficiency in Ha’il Region, Saudi Arabia.   This study has provided insights into the population’s awareness, attitudes and practices toward Vitamin-D, which can guide educational initiatives, policy formulation and preventive strategies to improve public health outcomes in the Hail region.   Objectives:   Assess knowledge of respondents on the sources of Vitamin-D Assess knowledge of respondents on sign and symptoms and of Vitamin-D deficiency Assess awareness of respondents on the importance of sunlight Assess attitude of respondents towards Vitamin-D rich foods and outdoor practices Correlate knowledge of those respondents having low Vitamin-D levels with demographic variables, knowledge, attitude and practices

Our study design was a descriptive comparative cross-sectional design was employed to assess knowledge, attitude and practices regarding Vitamin-D deficiency among adults in the Ha’il region. The study was conducted online using a self-administered questionnaire distributed across digital platforms and social media to reach adults residing in the Hail region, Saudi Arabia. The questionnaire was pretested on 10 randomly selected adults in order to maximize reliability and minimize ambiguity in understanding any question.   The estimated sample size for the study came out 306 participants. This number ensured statistical validity and adequate representation of the population in the Hail region, considering expected non-response rates. A questionnaire was written in English and later translated in Arabic by a linguistic expert. The Arabic form was retranslated in English in order to verify its reliability. The Arabic form was fed on Google Form. Pretesting was done on 10 respondents in order to ensure the accuracy and validity of the data by checking for unclear questions and confusing instructions. The link of Google form was sent by WhatsApp and email to all contacts. There was a free choice to ignore the request if they did not consent to participate in the research. The target population includes adults (≥18 years) residing in the Hail region from various educational and occupational backgrounds. The inclusion criteria for our study were to recruit adults aged 18 years and above, residents of the Hail region, individuals able to read and understand Arabic and who voluntarily consent to participate. Exclusion criteria were respondents who submit incomplete questionnaires and those who had medical background as their responses could confound the results due to their prior correct knowledge on the issue.   Statistical Analysis was performed by the IBM SPSS Statistics version 23. After completion of sample size 306, data was transferred from google excel sheet to SPSS version 23 for descriptive and inferential analysis. Descriptive analysis was done in percentages and by graphic presentation. Inferential statistics was done by applying Pearson chi-square test. The respondents’ Vitamin-D levels were asked. The most widely accepted threshold for Vitamin-D deficiency is a blood 25-hydroxyVitamin-D (25(OH)D) level below 30 nmol/L.1-3 Relationship of knowledge of those respondents having low Vitamin-D levels with certain variables was done applying Pearson chi-square test, keeping level of significance p ≤0.05 (significance threshold p ≤0.05).

Demographic profile of respondents is shown in Table 1. Fifty one percent (156/306) of the respondents were between 18-28 years of age and 60.5% were males (185/306). University employees and students were 68.3% (209/306).   Table 1: Demographic profile of the respondents (n=306) Variables Frequency Percent Age (years) 18-16 47 15.4 18-28 156 51 28-38 34 11.1 38-48 29 9.5 48-58 23 7.5 >58 17 5.6 Gender Male 185 60.5 Female 121 39.5 Educational Level No formal Education 6 2 Elementary School 10 3.3 High School 59 19.3 Middle School 22 7.2 University 209 68.3 Area of Residence Urban 262 85.6 Rural 44 14.4   The knowledge of the respondents on the nature of Vitamin-D is shown in Table 2. Majority (160/306=52.3%) knew that it is a fat-soluble vitamin, however the daily recommended dose was not known by 48% (147/306). The adequate blood level was known by just 39.2% (120/306).   The “vitamin is important for human body” was acknowledged by 94.8% (290/306). More than half (188/306=61.4%) of the respondents believed that food source is enough to acquire Vitamin-D. A small percentage (111/306=36.3%) knew the negative effect of sunblock cream on the absorption of Vitamin-D. The knowledge of respondents on drug interaction related to Vitamin-D was limited (92/306=30.1%).   Table 2: Knowledge on the Nature of Vitamin-D Variables Frequency Percent Vitamin-D Co-Factor 31 10.1 Enzyme 22 7.2 Fat-Soluble 160 52.3 Water- Soluble 39 12.7 Do not know 54 17.6 Adequate Blood Level (ng/mL) <10 14 4.6 10-30 50 16.3 30-50 120 39.2 >100 22 7.2 Do not know 100 32.7 Recommended daily dose (IU) of Vitamin-D 200 65 21.2 600 66 21.6 800 28 9.2 Do not know 147 48 Frequency of Vitamin-D level testing (in months) in a Vitamin-D deficient patient 1-3 49 16 3-6 89 29.1 6-9 44 14.4 9-12 16 5.2 Do not know 108 35.3 Vitamin-D is important for human body Yes 290 94.8 No 3 1 Do not know 13 4.2 Acquiring Vitamin-D from food is not enough Yes 71 23.2 It is enough 188 61.4 Do not know 47 15.3 Sunblock cream decreases the absorption of Vitamin-D Yes 111 36.3 No effect 102 33.3 Do not know 93 30.3 Vitamin-D has drug interaction with certain drugs Yes 92 30.1 No drug interaction 72 23.5 Do not know 142 46.4   In Table 3, the knowledge on different effects of Vitamin-D on human body is shown. Majority (259/306=84.6%) of study respondents knew that Vitamin-D is essential for bone and hair health. However, a significant percentage responded that Vitamin-D has effect on skin, vision and muscle integrity (197/306=64.4%, 197/306=64.4% and 209/306=68.3% respectively). Vitamin-D protects against weakness and chronic diseases were answered by 69.6% (213/306) and 52% (159/306) respectively.   Table 3: Knowledge on the importance of Vitamin-D to the Human Body Variables Frequency Percent Bone Health Yes 259 84.6 No 22 7.2 Do not know 25 8.2 Skin Health Yes 197 64.4 No 60 19.6 Do not know 49 16 Hair Health Yes 259 84.6 No 22 7.2 Do not know 25 8.2 Vision Health Yes 197 64.4 No 60 19.6 Do not know 49 16 Muscle Integrity Yes 209 68.3 No 46 15 Do not know 51 16.7 Body Immunity Increases 180 58.8 No effect 45 14.7 Do not know 81 26.5 Prevent against chronic diseases Yes 159 52 No 75 24.5 Do not know 72 23.5 Protection against weakness Yes 213 69.6 No 40 13.1 Do not know 53 17.3   Table 4 shows the knowledge regarding different sources of Vitamin-D. Majority (213/306=69.6%) knew that fatty fish ((such as tuna and salmon) are the major sources of Vitamin-D. More than half of the respondents (171/306=55.9% and 159/306=52%) marked egg yolk and liver as the major sources. Eighty-three percentage of respondents (254/306) had the knowledge that sunlight exposure is necessary to get Vitamin-D.   Table 4: Knowledge on Different Sources of Vitamin-D Variables Frequency Percent Food Items Fatty fish (such as tuna and salmon) Yes 213 69.6 No 45 14.7 Do not know 48 15.7 Egg yolk Yes 171 55.9 No 50 16.3 Do not know 85 27.8 Whole wheat Yes 90 29.4 No 106 34.6 Do not know 110 35.9 Cod Liver Oil Yes 145 47.4 No 66 21.6 Do not know 95 31 Liver Yes 159 52 No 64 20.9 Do not know 83 27.1 Red Meat Yes 135 44.1 No 74 24.2 Do not know 97 31.7 Exposure to Sunlight Yes 254 83 No 13 4.2 Do not know 39 12.7   Table 5 shows knowledge of study participants on different reasons of Vitamin-D deficiency. It was revealed that insufficient sunlight exposure and malabsorption were labelled as the causes by 69.6% (213/306) and 52.9% (162/306) followed by diet poor in Vitamin-D (206/306=67.3%). Renal diseases were not labelled as the cause of Vitamin-D deficiency by 41.2% (126/306) of respondents.   Table 5: Knowledge on Different Reasons of Vitamin-D deficiency Variables Frequency Percent Insufficient Sun Exposure Yes 213 69.6 No 54 17.6 Do not know 39 12.7 Malabsorption Yes 162 52.9 No 70 22.9 Do not know 74 24.2 Old Age Yes 117 38.2 No 121 39.5 Do not know 68 22.2 Physical Inactivity Yes 134 43.8 No 99 32.4 Do not know 73 23.9 Diet Poor in Vitamin-D Yes 206 67.3 No 45 14.7 Do not know 55 18 Kidney Diseases Yes 64 20.9 No 126 41.2 Do not know 116 37.9   Figure 1 shows different timings (reported by respondents) that are ideal for sunlight exposure in order to have adequate Vitamin-D in body. The time between 6am and 8am is reported by 35.6% (109/306).     Figure 1: Ideal time for sunlight exposure to get Vitamin-D   As shown in Figure 2, about half of respondents (159/306=52%) got information about Vitamin-D from social media followed by health care practitioners (58/306=19%).     Figure 2: Source of knowledge on Vitamin-D (n=306)   Table 6 reveals different attitude of respondents towards Vitamin-D. Around 50% of the respondents were concerned about their Vitamin-D level and wanted to know the symptomatology of Vitamin-D deficiency (165/306=54% and 164/306=53%).   Table 6: Attitude towards Vitamin-D Variables Frequency Percent Vitamin-D is vital for overall health Yes 290 95 No 16 5 Exposure to Sunlight is necessary for Vitamin-D synthesis in body Yes 213 69 No 93 31 Concerned with Vitamin-D blood level Yes 165 54 No 141 46 Concerned to know about Vitamin-D deficiency associated symptoms Yes 164 53 No 142 47   Table 7 shows different practices of respondents related to Vitamin-D. Around half (164/306=53.6%) of respondents had blood level assessment for Vitamin-D. Outdoor day time activities were performed by 52% (159/306). Fifty percentage (154/306) of respondents covered themselves (use umbrella or hat and apply sun block cream) while going outside during the daytime.   Table 7: Practices towards Vitamin-D Variables Frequency Percent Ever had blood level assessment for Vitamin-D Yes 164 53.6 No 142 46.4 Outdoor day time activities performed periodically Yes 159 52 No 147 48 While going outside during daytime, wear hat, use umbrella and apply strong sunblock cream Yes 154 50 No 152 50   Table 8 shows the knowledge of respondents regarding different symptoms of Vitamin-D deficiency. Majority (225/306=73.5%) knew that there is joints and bone pain. Muscle pain and mood changes also occur in Vitamin-D   deficient patients (answered by 183/306=59.8% and 249/306=81.4% of respondents). Regarding the symptomatology among children, 133/306=43.5% and 124/306=40.5% of respondents did not know that deformed knee joints, delayed walking could occur. Just 165/306=53.9% knew that there is delayed tooth eruption if the child is Vitamin-D deficient.   Table 8: Different symptoms of Vitamin-D deficiency Variables Frequency Percent Joints and bone pain Yes 225 73.5 No 21 6.9 Do not know 60 19.6 Muscle pain Yes 183 59.8 No 38 12.4 Do not know 85 27.8 Mood changes Yes 249 81.4 No 10 3.3 Do not know 47 15.4 Deformed knee joints in children Yes 136 44.4 No 37 12.1 Do not know 133 43.5 Delayed walking in children Yes 153 50 No 29 9.5 Do not know 124 40.5 Delayed tooth eruption in children Yes 165 53.9 No 31 10.1 Do not know 110 35.9   As shown in Figure 3, just 53/306=17.3% of study participants had normal blood levels of Vitamin-D, majority (142/306=46.5%) did not know as they never had assessment. Among study respondents, the prevalence of Vitamin-D deficiency was 106/306=34.6%.     Figure 3: Different levels of Vitamin-D among respondents   Results of cross tabulation (between the responses of those having low Vitamin-D levels with certain variables) is shown in Table 9. Regarding the demographic profile, there was no association with any specific age group, deficiency was found in every age group (p=0.179) however most of the male respondents were Vitamin-D deficient (p=0.002). There was no significant association of educational level with Vitamin-D deficiency (p=0.379). Majority of respondents did not know the importance of Vitamin-D for health and its daily recommended dose (p<0.05). Respondents having low levels of Vitamin-D had lack of knowledge on food items containing Vitamin-D (p<0.05) lacking (p<0.05). Those respondents did not perform outdoor day time activities periodically (p<0.05). The knowledge on different symptomatology is also significantly lacking among Vitamin-D deficient respondents (p<0.05).   Table 9: Relationship of knowledge of those respondents having low Vitamin-D levels with demographic variables, knowledge, attitude and practices. (Application of Chi-Square Test, keeping level of significance p ≤0.05) Variable Category Low Vitamin-D Level: n (%) χ2 p-value Gender Male 229 (75%) 14.929 0.002 Educational Level No formal Education 137 (45%) 12.866 0.379 Elementary School 140 (46%) High School 122 (40%) Middle School 122 (40%) University 113 (37%) Nature of Vitamin-D Recommended Daily Dose Do not know 205 (67%) 31.872 0.000 Important for overall health Do not know 203 (66%) 19.679 0.003 Knowledge regarding food items containing Vitamin-D Fatty Fish Not a source 177 (58%) 12.303 0.056 Egg Yolk Not a source 211 (69%) 15.651 0.016 Cod Liver Oil Not a source 189 (62%) 12.693 0.048 Liver Not a source 203 (66%) 12.777 0.050 Red Meat It is a source 223 (73%) 8.237 0.021 Knowledge on reasons of Vitamin-D deficiency Ideal time for sun exposure 6am-8am 208 (68%) 7.317 0.006 Malabsorption No related 177 (58%) 9.892 0.097 Old age Not related 174 (57%) 7.988 0.239 Physical Inactivity Not related 177 (58%) 5.788 0.049 Diet rich in Vitamin-D Not necessary 189 (62%) 4.986 0.046 Kidney diseases Not related 238 (78%) 8.233 0.949 Effect of Sunblock Cream on the absorption of Vitamin-D Not effect 214 (70%) 13.099 0.055 Attitude towards Vitamin-D deficiency Concerned to know Blood Vitamin-D level Yes 217 (71%) 5.770 0.005 Outdoor day time activities Not usual 183 (60%) 9.492 0.020 Knowledge on Symptomatology Bone and body pain No effect 214 (70%) 16.067 0.013 Mood changes No effect 205 (67%) 4.987 0.003 Delayed walking in children No effect 203 (66%) 6.098 0.000 Deformed knee in children No effect 189 (62%) 6.143 0.007 Delayed tooth in children No effect 198 (65%) 18.735 0.005

Based on multiple previous well documented studies, Vitamin-D deficiency considered a public health issue in Saudi Arabia. Even though the knowledge, attitudes and practices (KAP) related to Vitamin-D among various Saudi populations, including university students, adults, children and healthcare professionals has been assessed, the general awareness of Vitamin-D importance, sources, recommended intake and optimal sun exposure is often lacking. It is also noticeable that cultural, social and environmental barriers limiting effective practices, has not been well studied in Hail Region. [4,9,12-14].   In our study, more than half of the participants were young adults aged 18-28 years and male. In correlation to previous regional studies, most of them are well-educated and two-thirds holding university degrees [3,15-17]. Regardless their educational level, a noticeable critical gap in Vitamin-D knowledge reported. Although most respondents correctly identified Vitamin-D as a fat-soluble vitamin and agreed on its importance for human health, around half did not know the recommended daily intake and only 39.2% correctly identified the adequate serum Vitamin-D level.   In correlation with previous international, this finding highlights the discrepancy between the general awareness of Vitamin-D role and actionable knowledge such as appropriate dosage, indications for testing and optimal serum levels 5-17). It is also suggested that educational advantages alone do not ensure health awareness in Vitamin-D nutritional domain, reinforcing the need for public health interventions even among the college students and among a young, well- educated population [18].   Understanding the physiological roles of Vitamin-D showed in this study reported mixed results. the awareness of Vitamin-D’s role for bone and hair health was higher compared to its role in muscle integrity, immunity and chronic disease prevention. This selective understanding might reflect the long-standing public health campaigns and clinical emphasis on osteoporosis and skeletal disorders, in contrast to limited alertness of Vitamin-D’s contribution to muscle function, physiology and its relation to different organs, may lead to reduce motivation for screening and adherence to supplementation, particularly among younger and otherwise healthy individuals. Similar misconceptions have been reported globally, indicating a persistent need for public education on the non-skeletal benefits of Vitamin-D [19].   There was a disparity in knowledge regarding Vitamin-D deficiency manifestations. Vast majority of participants were familiar with musculoskeletal symptoms and mood changes. In contrast, the knowledge of pediatric manifestations such as delayed walking, tooth eruption and knee deformities was limited. This may lead to delay diagnosis and miss early intervention and prevention of Vitamin-D deficiency in children. these findings indicate the need for targeting parents and caregivers through health promotion and emphasizing on the role of Vitamin-D for early childhood growth and development.   When it comes to people's awareness of dietary sources of Vitamin-D, the result is contradictory. while many individuals correctly recognize fatty fish, eggs and liver as sources, a remarkable number of participants are unaware that cod liver oil and red meat also contribute to Vitamin-D intake. Notably, 83% acknowledged sunlight as a major natural source; however, confusion existed regarding the optimal time for sun exposure, with many selecting early morning hours (6-8 AM), which provide limited UVB radiation for Vitamin-D synthesis. In contrast, international evidence suggests that exposing arms and legs (or equivalent skin area) to sunlight for 5-15 minutes at noun, 2-3 times per week, is sufficient for Vitamin-D synthesis in light-skinned individuals [20,21]. The misconception reported in our study believed to contribute to inadequate endogenous Vitamin-D production in Hail populations due to sun avoidance or incorrect timing than insufficient sunlight exposure like: malabsorption and inadequate diet. Nonetheless, a notable number failed to link kidney disease or aging with this deficiency, highlighting the need for improved public awareness of the physiological and pathological factors that affect Vitamin-D metabolism.   Only half of the respondents reported undergoing Vitamin-D testing or participating in regular outdoor activities indicating that Vitamin-D Practice are not ideal. additional behaviors that may further reduce Vitamin-D synthesis such as using hats and umbrellas were noticed. These findings highlight a behavioral contradiction: while participants recognize the importance of sunlight, protective habits and lifestyle patterns may limit sufficient exposure [20]. In parallel to previously reported high rates in Middle Eastern populations [4,6], Among the participants who knew their Vitamin-D level, 34.6% reported Vitamin-D deficiency. Other 46.4% of participants were unaware of their Vitamin-D status, highlighting the lack of engagement in annual visit and healthcare maintenance visits.

Overall, the results indicate remarkable gap between general awareness and specific actionable knowledge among residents of the Ha’il region. Despite high level of awareness of Vitamin-D’s importance and major sources, the knowledge about dosage, sunlight physiology, food sources and clinical symptoms found to be suboptimal. additionally, the behavior aimed at protecting against Vitamin-D deficiency such as: sun exposure timing and preventive practices was poor and the need for targeted educational interventions.   Limitations It was a cross-sectional, online survey- based study done in a single region, hence there is an issue with generalizability. There is a chance of potential response bias and self-reported data.   Ethical Statement Participant did not incur any financial expenses during the research. Ethical approval was obtained from the Ethical Review Board (ERB) of University of Ha’il ((H-2025-931). This study was conducted according to the principles of the Helsinki Declaration (Ethical Principles for Medical Research Involving Human Subjects). The online questionnaire link was shared via social media and institutional platforms. Informed consent was obtained electronically before participants proceed to the questionnaire. Anonymity and confidentiality were maintained. Participants’ knowledge, attitude and practices were asked related to Vitamin-D by multiple- choice questions.