DEMOGRAPHIC AND BEHAVIORAL CHARACTERISTICS OF DIETARY SUPPLEMENT USE AMONG UNIVERSITY STUDENTS: A CROSS-SECTIONAL ANALYSIS BY YEAR OF STUDY

ABSTRACT

The study reveals that 1st-3rd-year students have a more positive view of dietary supplements, perceiving them as effective and safe for long-term use, while 4th-7th-year students are more cautious, especially regarding doctor recommendations and long-term safety. Both groups primarily use internet resources for information, but 4th-7th-year students are more influenced by advertisements. To promote safe supplement use, targeted educational initiatives should be implemented, focusing on safe usage and potential risks. Healthcare professionals need evidence-based guidelines for supplement recommendations. Additionally, research on the long-term effects and interactions of supplements should be encouraged. Stronger regulations on supplement quality and advertising are essential to ensure safety and informed decision-making among students and consumers.

АННОТАЦИЯ

Исследование показало, что студенты 1-3 курсов имеют более позитивное мнение о диетических добавках, считая их эффективными и безопасными для длительного использования, в то время как студенты 4-7 курсов более осторожны, особенно по вопросам рекомендаций врачей и долгосрочной безопасности. Обе группы в основном используют интернет-ресурсы для получения информации, однако студенты 4-7 курсов чаще ориентируются на рекламу. Для обеспечения безопасного использования добавок необходимо внедрить целевые образовательные инициативы, ориентированные на безопасное применение и потенциальные риски. Медицинским специалистам нужно предоставить доказательные рекомендации по использованию добавок. Также важно поощрять исследования долгосрочных эффектов добавок и усилить регулирование качества и рекламы для обеспечения безопасности и информированного выбора.

Keywords: dietary supplements, students, supplement consumption, safety, effectiveness.

Ключевые слова: биологически активные добавки, студенты, потребление добавок, безопасность, эффективность.

Introduction:

Dietary supplements (DS) are increasingly popular in countries like the U.S. and the U.K., with Americans spending $28.1 billion on them in 2010. The most common types of DS consumed include multivitamins, botanicals, amino acids, and individual vitamins like C, E, and B12. People generally use DS to promote general health, enhance performance, treat specific conditions, or improve nutrition. The surge in DS use is partly due to the Dietary Supplements Health and Education Act (DSHEA) of 1994, which expanded the availability of these products and reduced regulatory oversight. However, some experts warn that, based on available evidence, these supplements may offer no significant benefits for well-nourished adults and could even be harmful [1-5]. In the USA, 58% of adults report using dietary supplements (DS), with European usage ranging from 2% to 66%, varying by country and gender [6,7]. DS users typically differ from non-users in socio-demographic factors, such as age, income, and education, with women more likely to use them than men. Supplement use is often linked to healthier habits, including better diets, higher physical activity, and tobacco avoidance [8].

Given the growing popularity of DS among university students, it is essential to raise awareness and improve knowledge on safe usage practices. Medical students, who are future healthcare professionals, should have a thorough understanding of the risks and benefits associated with DS consumption. Incorporating education on evidence-based guidelines for recommending supplements can help shape informed decision-making not only in their personal use but also in advising patients. Integrating DS education into medical curricula will help ensure that future healthcare providers are equipped with the knowledge to guide patients in making safe and effective choices regarding supplementation, thereby contributing to better overall health outcomes and reducing the risks of misuse [9,10]. The aim of the study is to analyze the demographic and behavioral characteristics related to the consumption of dietary supplements among university students, focusing on differences based on academic year. The study seeks to understand patterns of supplement use, sources of information, perceptions of effectiveness, and safety concerns, with the goal of informing educational initiatives, healthcare guidelines, and policy recommendations to promote safe and informed dietary supplement use.

Methods: The study was descriptive and cross-sectional in nature. In the first phase, a structured questionnaire was developed, including both closed and semi-open questions. To assess its validity and clarity, the questionnaire was reviewed by experts in the medical field. The survey was conducted online using the Google Forms platform. A link to the questionnaire was sent through university email addresses. Participation in the study was entirely voluntary and anonymous. Before beginning the survey, participants were provided with information about the study's objectives and asked to confirm their informed consent by checking a box in the relevant field. The collected data were processed using descriptive statistical methods. To analyze differences between groups, the Pearson chi-square (χ²) test and p-values were used to assess statistical significance. A p-value of < 0.05 was considered statistically significant. Data processing was carried out using Excel and SPSS software.

Results: The table 1 presents an analysis of demographic and behavioral characteristics related to the consumption of dietary supplements (DS) based on the academic year. In the under-18 age group, there is a significant predominance of respondents in the 1st to 3rd years (6.9%) compared to the 4th to 7th years (3.0%), which is statistically significant. The majority of participants aged 18-24 are found in both the 1st to 3rd years (53.4%) and the 4th to 7th years (69.8%). In the 25 and older age group, 1st to 3rd-year students account for 39.7%, while 4th to 7th-year students make up 30.2%. In terms of gender, women predominate in the 1st to 3rd years (55.0%), while their share significantly increases in the 4th to 7th years (70.3%), with statistical significance. Regarding DS consumption, most respondents take them occasionally (54.1%), with no significant differences observed between academic years. The most commonly consumed types of DS are vitamins (64.5%), with a higher usage among 1st to 3rd-year students (68.2%) compared to 4th to 7th-year students (61.6%). The frequency of DS intake varies, with the largest group using them as needed (36.9%), and no significant differences in consumption frequency between academic years. In terms of duration of supplement use, a higher percentage of 4th-7th-year students (55.2%) have been using dietary supplements for less than a month compared to 1st-3rd-year students (41.2%), a difference that is statistically significant (p = 0.032). However, 1st-3rd-year students report using supplements for longer periods, such as several years (22.1%) compared to 4th-7th-year students (11.6%).

Regarding how students learned about dietary supplements, Internet resources are the most common source of information, with 31.7% of respondents overall relying on them. There is little difference between the two groups in this regard, but a higher percentage of 4th-7th-year students (7.6%) learned about supplements through advertisements compared to 1st-3rd-year students (1.5%) (p = 0.004). Doctor's recommendations are another significant source, with 28.7% of all respondents mentioning them.

When asked about the results of taking dietary supplements, most students rate the results as positive (44.2%), with 1st-3rd-year students being more likely to report very positive results (33.6%) compared to 4th-7th-year students (20.9%) (p = 0.058). There were also some negative ratings, with 2.3% of both groups reporting negative changes. Regarding the effectiveness of dietary supplements, 42.9% of all students felt they were effective, but not in all cases, with a higher percentage of 4th-7th-year students (45.3%) agreeing compared to 1st-3rd-year students (39.7%) (p = 0.028). Furthermore, 1st-3rd-year students were more likely to rate supplements as very effective (23.7%) compared to 4th-7th-year students (14.0%).

Table 1.

Demographic and Behavioral Characteristics of Dietary Supplement Consumption by Academic Year

The table 2 also examines whether doctors should recommend dietary supplements. While most students in both groups think doctors should recommend them with caution, 4th-7th-year students are more likely to believe that doctors should not recommend them at all (23.8%), compared to 1st-3rd-year students (9.2%) (p = 0.002). A larger proportion of 1st-3rd-year students (32.8%) believe that doctors should recommend supplements, although a significant number (35.1%) think it depends on the situation. As for the safety of long-term use of dietary supplements, 25.2% of 1st-3rd-year students think they are safe, compared to just 12.2% of 4th-7th-year students (p = 0.001). Both groups, however, agree that the safety depends on the supplement, with 34.7% of all students sharing this view. Regarding factors that can affect the effectiveness of dietary supplements, the quality and composition of the supplements is considered the most important factor by 32.3% of all respondents. More 4th-7th-year students (48.8%) cited this compared to 1st-3rd-year students (36.6%) (p = 0.007). Other factors like individual characteristics and dosage were also considered but to a lesser extent. When it comes to physiological changes to monitor while using dietary supplements, 1st-3rd-year students were more likely to highlight changes in skin, hair, and nails (29.8%) compared to 4th-7th-year students (22.1%). There were no significant differences in terms of changes in energy levels or general well-being. Lastly, when asked about aspects of dietary supplements requiring further research, the need for more studies on long-term health effects was highlighted by 28.1% of students, with no significant differences between the two groups (p = 0.084). Other areas like interaction with drugs and efficacy in treating specific diseases were also mentioned.

Table 2.

 Student Perceptions and Usage of Dietary Supplements by Academic Year

Discussion The findings from the analysis provide valuable insights into the dietary supplement consumption patterns of university students, with differences emerging based on academic year. The data suggest that students in the 1st-3rd years tend to view dietary supplements more favorably in terms of effectiveness and safety, while those in the 4th-7th years exhibit greater caution, particularly regarding the recommendations from healthcare professionals and the long-term use of supplements. This distinction could be attributed to varying levels of knowledge and experience, as older students may have encountered more information and perhaps negative experiences that shape their cautious approach. Similarly in our results, authors found that the consumption of dietary supplements (DSs) among Italian undergraduates, revealing that 71.5% used supplements, with women more likely to follow doctor's prescriptions and report adverse effects. The use of DSs was associated with sex, dietary regimens, and participation in sports, particularly individual sports, highlighting the need for educational interventions on supplementation [11]. Other research on the prevalence, types, and reasons for dietary supplement (DS) use among university students, along with their knowledge and information sources, revealed that 68% of students used DS, with females being more likely to use them. The primary reason for usage was to improve energy and vitality, and no significant associations were found between DS use and factors such as smoking, BMI, or exercise [12]. The study found that 70.2% of participants used dietary supplements, with many reporting side effects such as headaches, sleeplessness, and irritability, but no positive impact on academic achievement was identified. A significant portion of participants held incorrect beliefs about the benefits of supplements for academic performance and their safety, with 51.1% thinking supplements could enhance achievement and 46.4% perceiving them as risk-free [13].

One key observation is that both groups rely heavily on internet resources for information about supplements, yet 4th-7th-year students appear to be more influenced by advertisements. This is an important factor to consider, as the internet provides an array of both credible and non-credible sources. The potential for misleading advertisements underscores the need for stricter regulations in supplement marketing to ensure that students and the broader public receive accurate, evidence-based information. The results also highlight the significant role that doctor recommendations play, with both groups indicating a preference for advice from healthcare professionals. However, there is a noticeable divergence in attitudes toward whether doctors should recommend supplements.  While most students agree that doctors should be cautious, the 4th-7th-year students are more likely to believe that supplements should not be recommended at all. The study found that 41% of participants used dietary supplements (DS), with predictors including gender, physical activity, BMI, cigarette smoking, chronic diseases, nutritional knowledge, special diet usage, and adherence to the Mediterranean diet, highlighting the need for further research on DS contribution to overall nutrient intake [14].  The study found that 60.9% of university students in Jordan used dietary supplements, with the most common motivation being health maintenance, but revealed poor knowledge, negative attitudes, and high-risk practices among users. Factors such as normal weight, lower family income, and being an undergraduate student were significantly associated with higher DS usage, indicating the need for improved nutrition education to ensure safe and informed practices [15]. This caution may stem from increased awareness of the possible risks and side effects of supplements, especially in the context of polypharmacy or interactions with other medications.

When assessing the effectiveness of supplements, a greater proportion of 1st-3rd-year students rated their experiences positively, with many reporting "very positive" results. This suggests that students with less exposure to supplement use may have higher expectations or fewer experiences with negative outcomes. In contrast, 4th-7th-year students, who likely have more experience, might have a more nuanced understanding of the limited benefits that supplements can offer in specific cases. This calls attention to the importance of setting realistic expectations around the use of dietary supplements.

The analysis also reveals that while students generally view vitamins as the most commonly used dietary supplement, there is a notable difference in the duration of use. A higher percentage of 4th-7th-year students report using supplements for less than a month, indicating that older students may be more cautious or selective in their use of supplements compared to their younger counterparts, who may be more experimental in their health choices.

Another interesting finding is the shared belief that further research is necessary to better understand the long-term health effects and safety of supplements. Both groups expressed a strong interest in gaining more knowledge about supplements, particularly in terms of their interactions with other medications and their potential to treat specific diseases. This aligns with the growing demand for evidence-based information, especially given the rising global trend of supplement consumption.

The differences between 1st-3rd-year and 4th-7th-year students suggest that there is a need for tailored educational interventions that address the specific concerns of each group. For younger students, education could focus on safe usage, while older students may benefit from more in-depth discussions about potential risks, interactions, and the limitations of dietary supplements. Furthermore, healthcare professionals should be encouraged to engage with students and provide personalized, evidence-based advice.

Given the reliance on internet resources and the influence of advertisements, there is a clear need for stronger regulation of the supplement industry, particularly in terms of advertising and product quality. By ensuring that students have access to accurate information, the likelihood of misuse or unrealistic expectations could be reduced.

Conclusion: The analysis shows that 1st-3rd-year students generally have a more positive outlook on dietary supplements, perceiving them as effective and safe for long-term use. In contrast, 4th-7th-year students are more cautious, especially regarding doctor recommendations and long-term safety. Both groups primarily rely on internet resources for information, but 4th-7th-year students are more influenced by advertisements. To ensure safe and informed dietary supplement use, targeted educational programs should be implemented for students at different academic levels, focusing on safe usage and risks. Healthcare professionals should receive evidence-based guidelines for recommending supplements. Additionally, research on the long-term effects and interactions of supplements should be promoted to aid informed decision-making. Regulations must be strengthened to ensure the quality and safety of supplements, while advertising should be strictly controlled to ensure truthfulness and scientific backing. These combined efforts will empower students and consumers to make better, safer choices regarding dietary supplements.

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