https://orcid.org/0000-0003-4292-0780
Abstract
Due to little dietary supplement regulation and misinformation online, there is a need to educate consumers on them, which could be addressed using a higher education course to provide students resources to evaluate supplement information. The objective of this paper was to describe the design of a 3-credit dietary supplement elective course (HNF 102- Dietary Supplements: Evidence vs Hype) for undergraduate students. Furthermore, to analyze student perspectives and skills developed resulting from course completion. HNF 102 is a 5-unit asynchronous online course which consists of the following units: Unit (1) provides an overview of nutrition and dietary supplements; Unit (2) describes dietary supplement regulation; Unit (3) provides credible sources of dietary supplement information and tools to evaluate dietary supplement information; Unit (4) describes research on dietary supplements claimed to improve general health; Unit (5) describes research on dietary supplements purported to improve performance. A process evaluation inquiring about student opinions following course completion was offered as an extra credit opportunity. Overall, students indicated course lecture materials and assignments improved their understanding of dietary supplements and their ability to evaluate dietary supplement information. Dietary supplement undergraduate courses can be an effective method to improve consumer dietary supplement health literacy.
IMPACT STATEMENT
Due to the large amount of dietary supplement misinformation online, there is a need to educate consumers on them. This manuscript describes how an elective dietary supplement course was designed for undergraduate students to provide students with tools for evaluating dietary supplement information and where to find credible sources of dietary supplements. Upon completion of the course students reported that course lecture materials and assignments improved their understanding of dietary supplements and their ability to evaluate dietary supplement information. College elective courses could be a method to improve dietary supplement knowledge among college students.
REVIEWING EDITOR:
Introduction
Dietary supplement (DS) use in individuals over the age of one in the United States (US) has increased to 56% in 2018, up from 49% in 2007 (Cowan et al., Citation2023). The largest increase in prevalence of DS use during that time was among older adults (> 70 years of age) and younger adults (between 19 and 30 years of age). These trends are expected to continually increase as the US DS market is projected to be worth $56.7 billion in 2024, up from $41.4 billion in 2020 (Mikulic, Citation2023).
Despite their increasing market share, DSs remain largely unregulated in the US. While the Food and Drug Administration (FDA) is tasked with monitoring DSs marketed for sale, they do not have the capacity to ensure that all manufacturers follow Good Manufacturing Practices in product development. This has led to numerous DSs on the market with unsubstantiated claims on health-related outcomes, lack of quality assurance on product composition, and reports of harmful contaminants present in DSs (Tucker et al., Citation2018; Van Thuyne et al., Citation2006; Whiting, Citation1994). During the period of 2007 to 2021, 1068 unique products from the FDA’s Supplements Database were reported to contain active pharmaceutical ingredients (White, Citation2022). Further, the Drug-Induced Liver Injury Network found that liver injuries due to non-bodybuilding supplements were more severe than liver injuries purported from conventional medicine based on a higher liver transplant rate for individuals taking non-bodybuilding supplements (Navarro et al., Citation2014). Taken together, it is imperative to educate both consumers and allied health professionals on the regulatory shortfalls of DSs.
Although DSs remain a major public health concern, they are increasingly popular as US adults try to improve and maintain their health. Unfortunately, between the health-related marketing of DSs and the rampant nutrition misinformation online, consumers are often left on their own to determine the safety and effectiveness of these products. Even more problematic, when the public is exposed to scientific information that contradicts their beliefs, their opinions may still not change. For example, Duarte et al. (Citation2022) performed a survey to examine perceptions of the healthiness of coconut oil compared to other oils after respondents were provided information that coconut oil did not provide health benefits (Duarte et al., Citation2022). Interestingly, 73.5% of the respondents who originally considered coconut oil healthy compared to other oils, reported that the new countering information did not change their opinion.
Additionally, in the current informational age, anecdotal evidence is often held in high regard and consumers have increased accessibility to online reviews for various products, but there are many concerns around the validity/trustworthiness of these online reviews. For example, one study found that 66.6% of online consumer reviews for testosterone boosting DSs were considered untrustworthy or suspicious using ReviewMeta filtration software (Balasubramanian et al., Citation2019). This filtration software helps to identify fake or biased online consumer reviews, which may not even cross a typical consumer’s mind as they review a product’s purported 4.8-star rating. An educated consumer should not rely solely on anecdotal evidence to make informed choices but consider what types of DS information are considered credible and where to locate them.
As DSs continue to rise in popularity, there is a growing need for educating the general public on the regulation, safety, and purchasing of DSs. Little has been published describing the creation of DS education courses within university curriculums. At least two publications have stemmed from Doctor of Pharmacy programs that have added DSs and/or micronutrient courses to their curriculum, providing practicing pharmacists with a background on DSs, and the skills and knowledge required to appropriately educate their patients with success (Bonafede et al., Citation2009; Islam, Citation2013). For example, Islam (Citation2013) found that an elective course on vitamins and minerals improved Doctor of Pharmacy student knowledge in counseling patients on the safe and appropriate use of vitamin and mineral supplements (Islam, Citation2013).
As we considered the scientific literacy of our own undergraduate students, we sought to create a course that helps to better inform the undergraduate student population about DS regulation and use in the US. The objective of this paper was to describe the design of a DS elective course for undergraduate students. Additionally, a secondary objective was to analyze student perspectives and skills developed upon course completion.
Purpose for creating the elective course
HNF 102- Dietary Supplements: Evidence vs Hype (denoted as HNF 102 from hereon) is a 3-credit asynchronous online course available as an elective at Michigan State University (MSU). There are no course pre-requisites. The course was created as a component of the nutritional sciences program redesign at MSU which has been discussed prior (Becker et al., Citation2020). In short, the course was designed to meet the needs of both science and non-science majors alike, providing those students with the knowledge to help them make informed DS purchases. As such, the major focus of the course’s learning goals is centered around helping students better understand the DS landscape and help facilitate a more scientifically literate consumer. The course instructional objectives and learning outcomes are listed in .
Table 1. HNF 102 course instructional objectives and learning outcomes.
Unit description and rationale
In brief, the course follows a condensed, logical progression of nutrition and DS information. Students are first introduced to basic nutrition concepts, followed by units on DS regulations, evaluating the evidence of DSs, and finally examining general and specific health outcomes associated with various DSs. includes the course units and subunits of which select topics are discussed in detail as examples in the subsequent sections.
Table 2. HNF 102 course units and subunits.
Unit 1: Nutrition overview and dietary supplement introduction
Since the course does not require any prerequisite courses, the first unit focuses on providing a basic knowledge framework of nutrition and health, how nutrient recommendations are determined, and an introduction to regulatory definitions of food items and DSs.
1.2 and 1.3: What are proteins, carbohydrates, and fats? and what are micronutrients: vitamin a to zinc?
These lectures provide overviews of the different macro- and micronutrients, including basic classifications, their functions in the body, and issues with both excessive consumption and deficiencies that may manifest because of inadequate intake. Furthermore, there are current topic discussions, such as the controversy associated with the use of high fructose corn syrup as a sweetener and the rise in obesity and other metabolic diseases (Gropper et al., Citation2018).
1.4: Just what are dietary supplements and functional foods?
Dietary supplements and functional foods are defined for students to start distinguishing them from conventional foods and nutrition. Dietary supplements in the US are defined as pills, tablets, capsules, liquids, powders or bars that contain one or more of a dietary ingredient such as minerals, vitamins, herbs, enzymes, phytochemicals, and others (Dietary Supplement Health & Education Act, Citation1994). Furthermore, the purpose of a DS is to supplement the diet and not replace any nutrients otherwise consumed from a balanced diet. Functional foods are not clearly defined in the US but are generally considered foods or food substances that possess health and physiological benefits over the normal nutritional value (Temple, Citation2022).
By concluding Unit 1 with the definition of DSs and other food items, the instructor can more confidently move into the next unit with a specific focus on DS regulation.
Unit 2: Dietary supplement regulation
This section begins by describing the interesting history of DS regulation in the US. Most of the current regulation of DSs in the US began with the Dietary Supplement Health and Education Act (DSHEA) of 1994 (Dietary Supplement Health & Education Act, Citation1994). Prior to DSHEA, DS definition and regulation was primarily defined through the Federal Food et al. (Citation1938). This unit also explores other DS laws such as those from athletic governing bodies.
2.1: Dietary supplement regulation: the good
The curriculum was parsed out to separate basic DSHEA and other DS regulations into what can be considered positive and negative outcomes of the legislation. One potential benefit for consumers of DSs was the establishment of a new government agency that was created with adoption of DSHEA, the Office of Dietary Supplements located within the National Institutes of Health (Dietary Supplement Health & Education Act, Citation1994). The purpose of the Office of Dietary Supplements is to explore the role of DSs as efforts to improve US health care and to promote further scientific study of them to maintain and improve health.
The approval of DSHEA also required standardized labeling on DSs, like the Nutrition Facts found on food labels. This required DSs to identify on the label that the product itself was a DS, as well as the name of and quantity of each ingredient contained within (Dietary Supplement Health & Education Act, Citation1994). Further, DS labels must now include the label: “This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease” (Dietary Supplement Health & Education Act, Citation1994).
2.2: Dietary supplement regulation: the bad and the ugly
Under DSHEA, DSs could then use various label claims for marketing purposes. These include health claims, nutrient claims, and structure/function claims. While DS manufacturers must have evidence to substantiate these claims, research has shown that many of the structure/function claims on supplements possibly mimic health claims and are largely unsubstantiated without any scientific evidence (Avery et al., Citation2017). Dietary supplements available on the market prior to October 15, 1996, were grandfathered into DSHEA and were not required to undergo safety testing (Dietary Supplement Health & Education Act, Citation1994). Further, dietary supplements were considered Generally Recognized As Safe. The FDA can only take action against a DS manufacturer if the product poses an imminent hazard to public health or safety (Dietary Supplement Health & Education Act, Citation1994). This is in contrast to drugs which must be proven safe through clinical trials before becoming publicly available to consumers.
2.4: What about dietary supplement marketing and safety?
In this lecture, DS advertising is discussed, specifically the role of the Federal Trade Commission which published specific guidelines in the 2022 Health Products Compliance Guidance document (Commission, Citation2022). Dietary supplement safety is also included in this lecture, which describes how adverse events can be attributed to: (1) the ingredients themselves; (2) contaminated products; and (3) potential drug interactions of DSs (Wallace et al., Citation2013). Furthermore, where and how to report adverse events to the FDA is included. Although this resource is in place to alert authorities on adverse events attributed to DSs, few take advantage. In a cross-sectional study of 311 physicians, 71% reported encountering adverse events due to DSs in practice, however only 10% of them reported the adverse events (Pascale et al., Citation2016). Clearly, more emphasis is needed to inform healthcare practitioners and the public alike of where to report adverse events.
By providing an overview of the regulatory framework surrounding DSs in the US, students are often surprised that DSs do not have an approval process before hitting the shelves, that they frequently differ significantly than what the dietary supplement label suggests, and that harmful DSs are only pulled from the shelves after adverse events have been reported and undergone burdensome FDA investigations. From here, the instructor moves into Unit 3, which helps to provide the students with the tools needed to better evaluate DS claims and marketing.
Unit 3: How to evaluate dietary supplement information
The overall purpose of this unit is to begin introducing students to credible sources of information and provide them with the skills to evaluate DS claims and information.
3.1 and 3.2: What government websites pertain to dietary supplements? and other resources and how to evaluate a website
The first two lectures of this unit provide and discuss credible sources of information on DSs including information from the Office of Dietary Supplements, FDA, Human Performance Resource Center, other US government resources, Australian Sports Commission, the International Society of Sports Nutrition, etc. Non-credible sources of DS information are also included. Dietary supplement consumers need to know where to find credible, evidence-based sources of DS information amidst the ever-growing non-credible sources.
3.5: Evaluating evidence- quackery and credential mongering
The next “Evaluating Evidence” lecture is on quackery in nutrition and explains why we are so susceptible to it. Throughout this lecture, the instructor provides several questions to ask oneself when researching DS information. For example, informing the students to be wary of claims that persecute mainstream establishments, such as conventional medicine and the food supply.
3.6: Evaluating evidence- how to conduct your own experiments
The next “Evaluating Evidence” lecture is about how one could perform their own experiments to see if a DS is providing any benefit. The lecture includes methods and measurements one could employ to examine DS ingredient effectiveness. This includes using the most accurate method to measure the outcome that one has access to. It should be noted that the individual needs to maintain the same lifestyle habits (e.g. dietary pattern, physical activity, sleep) when taking the DS and when not taking it to make a valid comparison.
Following Unit 3, students have the skills and resources needed to evaluate DS claims and other information.
Unit 4: Dietary supplementation and general health
With the foundational knowledge of nutrition and DSs, as well as the skills needed to evaluate DS claims, the remainder of the course explores prominent/popular DSs and models how a scientist would begin to critically evaluate their potential health effects. In these last two units, the effects of select DSs on general health outcomes (Unit 4) and performance enhancement (Unit 5) are discussed. Oftentimes, information from systematic reviews and/or meta-analyses are presented in these lectures to provide students a summary of what is currently known around a particular DS and outcome.
4.1: Micronutrient supplementation and health
First in this lecture is a review of how nutrient recommendations are determined. Vitamins and minerals are presented first on their known mechanisms and effects in the body and then if there are any benefits to supplementation (vitamin D, vitamin B-12, folic acid, calcium, magnesium, and iron). The lectures go over data from various systematic reviews and meta-analyses examining the effects of long-term supplementation of vitamins and minerals on various health outcomes. Considerations with antioxidant supplementation are also discussed. Guidelines for dietary supplement use from the Academy of Nutrition and Dietetics is also included (Marra & Bailey, Citation2018).
4.2: Can herbs and phytochemicals cure or support health?
The next few lectures examine the effects of herbs and phytochemicals on different health outcomes. In the first of these lectures, the instructor provides a basic overview on herbs including connections with them and conventional medicine. The second half of this lecture explores various herbs purported to reduce the risk of or treat cardiovascular disease and/or cancer. While an exhaustive list is not feasible to include, the instructor chose a few and discussed each by first explaining the supposed claims and identified biological mechanisms before then going over the evidence and potential safety considerations. The end of the lecture highlights some of the concerns of using herbal remedies in lieu of conventional medicine as this can be a potential issue with consumers. For example, in an article by Johnson et al, cancer patients who chose to use alternative therapies over conventional medicine had a greater risk for death than those who did not (Johnson et al., Citation2018).
Unit 5: Dietary supplementation and performance enhancement
In the last section of the course, DSs purported to improve performance and/or body composition are discussed. Dietary supplement use is quite prominent among athletes worldwide (Daher et al., Citation2022). In a review by Garthe and Maughan (Citation2018), it was found that an estimated 40% to 100% of athletes in a given organization use DSs (Garthe & Maughan, Citation2018).
5.1: What are protein supplements? Can individual amino acids help me increase muscle mass?
The first lecture describes protein intake and amino acids supplementation. Although protein as a macronutrient was first introduced in lecture 2 of Unit 1, further protein effects on performance and body compositions are explored here. The instructor provides an overview of protein synthesis, protein digestion and absorption, and concepts on protein quality. Various types of protein supplements are described with an overview of protein sources and their effects on improving performance outcomes and body composition. The last portion of this lecture goes over supplementing various amino acids (i.e. glutamine, arginine, branched chain amino acids) to improve performance and/or body composition.
5.3: OTC hormonal boosters (testosterone and growth hormone boosters)
Lecture 3 focuses on research examining the effects of various DS ingredients purported to increase testosterone and growth hormone. The rationale is that an increase in either would improve performance and body composition (Fink et al., Citation2018). First, the instructor explains how testosterone is produced within the body and how it can exert effects which theoretically would improve performance and/or body composition. Prior to examining the evidence around various testosterone boosting DSs, the instructor includes a list of considerations one should use when examining the evidence and considering purchasing these types of supplements. For example, did the study examine healthy individuals or were they suffering from hypogonadism? Will the slight increase in testosterone lead to any meaningful, observed changes? Like prior lectures, identified mechanisms are included, along with any evidence of effectiveness. Prohormones and aromatase inhibitors and uncertainty around the effects of these are also briefly described. The last section of this lecture is on DS ingredients purported to increase growth hormone production which are summarized first by providing an overview of growth hormone physiological effects and the current state of the evidence of growth hormone boosting supplements regarding their effectiveness.
5.5: Sports nutrition recommendations
Lecture 5 contains a brief introduction to sports nutrition recommendations focusing on energy requirements, macronutrient compositions, and timing of intake which are discussed in greater detail in the Nutrition and Athletic Performance joint position statement from the American College of Sports Medicine, Academy and Nutrition and Dietetics, and the Dietitians of Canada (Thomas et al., Citation2016).
Course assessments
The course’s structure and assignments were developed using backward design (Wiggins & McTighe, Citation2005). Backward design has been suggested to be an effective practice for creating summative assessments in higher education as learning outcomes are defined first and then suitable assessments are determined to measure said outcomes (Kibble, Citation2017). A summative assessment is a higher-stakes assignment that measures student knowledge to inform if student learning is accomplished (Academy for Teaching & Learning, Citation2023). There are a total of two quizzes over the course of the 7-week summer semester to test basic knowledge retention and understanding. There are four major assignments spread throughout the course that help to reinforce the student’s scientific competency in evaluating dietary supplements. Additionally, the instructor utilizes Packback (Packback Inc., Chicago, IL) as an online forum tool to foster discussion and classroom engagement. The assessments parallel unit content.
The summative assessment for the course is the Dietary Supplement Review Assignment. For this assignment the students are asked to identify and review three different DS ingredients for effectiveness and safety. The purpose of this assignment is to: (1) identify DS claims for a specific ingredient; (2) ascertain potential mechanisms for identified DS ingredients; (3) evaluate the claims using peer-reviewed evidence; and (4) identify any potential side effects for each ingredient. Students are allowed to pick one DS product containing the three ingredients or they can pick three separate DS products. After identifying the DS ingredients, the student needs to identify specific claim(s) on the product and then will use those claims to answer required questions. Five peer-reviewed publications such as journal articles and evidence-based webpages are to be used to answer the remainder of the assignment. For each ingredient students are required to identify potential mechanisms linking the ingredient to the claim, and describe any research (i.e. human experimental studies) performed examining this topic. It is important for students to understand randomized clinical trials are critical for generating evidence as these studies provide the most persuasive evidence for a causal relationship (Samet et al., 2008). Important study characteristics to include would be participant descriptive information, supplement duration, specific product, supplement dosage, and measured outcome of interest. Further, the students need to indicate if the dosage provided in the product matches the dosages used in the studies. Lastly, the students are required to identify any other potential benefits and side effects for each DS ingredient.
Materials and methods
For the most recent iteration of this course (summer 2022), the overall class grade was 90.5 ± 9.22% for an enrollment of 69 students. Students have typically demonstrated a strong understanding of the course material in their final assignment. In addition to their evaluated understanding, we were also interested in whether students self-identified strengths or weaknesses in core content outcomes.
Process evaluation and assessment of the dietary supplement course
To evaluate whether students believe that the course helped improve their understanding of DSs, the instructor implemented a reflective process evaluation, which can be used to improve course development for future semesters. Some of the questions ask the student to report how their knowledge of and perceptions around various DS concepts have changed following completion of the course. Specifically, the questions focus on concepts from the first three units (Units 1–3) as these units provide the foundation and tools students would use to evaluate DS information. Completion of the process evaluation was voluntary and offered as an extra credit opportunity. This project was considered not human research by the MSU Institutional Review Board (STUDY00009151).
Results and discussion
Process evaluation results are presented in . Over half of enrolled students (57%; n = 39) completed the process evaluation. Overall, HNF 102’s lecture materials and assignments were valuable in improving student knowledge of DSs based on student process evaluation feedback. Similarly, Islam (Citation2013) observed that pharmacy students agreed that a vitamins and mineral course’s materials were valuable and that the course should be a part of the required curriculum (Islam, Citation2013). If examining responses for Unit 1 questions, most students agreed and strongly agreed that that lecture materials and assignments improved their understanding of macro- and micronutrients, what DSs are considered compared to foods, and what medical foods are (97.3%, 94.9%, and 94.9%, respectively). Similar relationships were observed for Unit 2 questions with 94.9% of respondents strongly agreeing or agreeing that the Unit 2 lecture materials and assignments improved their understanding of DS regulation overall. Furthermore, 97.4% reported that the Unit 2 lecture materials and assignments improved their ability to read a DS label and improved their understanding of potential DS safety concerns. Unit 3 process evaluation questions were mostly related to how this unit’s lecture materials and assignments improved their ability to evaluate DS information. 91.4% of respondents either strongly agreed or agreed that this unit’s materials and assignments improved their knowledge of what were considered credible DS information sources. Lastly, 94.4% of respondents reported that Unit 3’s lecture materials and assignments improved their ability to evaluate DS health claims and 91.7% reported that this unit’s materials and assignments improved their skillset of questions to ask when evaluating a dietary supplement. Taken together these results suggest that an undergraduate elective course can increase a student’s self-confidence and self-efficacy for evaluating DS information. Furthermore, completion of a DS elective course could improve one’s ability to educate others about DSs. For example, Bonafede et al. (Citation2009) reported that 57.4% of pharmacy students strongly agreed or agreed that a Doctor of Pharmacy elective DS course provided adequate DS information resources to aid them in providing care to patients using them (Bonafede et al., Citation2009).
Table 3. Process evaluation data for HNF 102 from summer 2022.
Conclusions
In summary, an elective, general education course was designed to educate undergraduate students on DS and how to evaluate DS information. A process evaluation revealed that the course’s materials and assignments improved students’ confidence in understanding DS definitions, regulations, labels, credible information sources, and their ability to evaluate DS health claims. Future research should follow up with former students and inquire about their current DS evaluation habits to examine the long terms effects of having completed the course.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Data availability statement
Data sharing is not applicable to this article as no new data were created or analyzed in this study.
Additional information
Notes on contributors
Tyler B. Becker
Tyler B. Becker PhD, CSCS, Michigan State University, sports nutrition, rural public health, exercise physiology.
Jenifer I. Fenton
Jenifer I. Fenton MPH, PhD, Michigan State University, diet modulating inflammation and diseases, feed consumption and fatty acid profile, colon cancer.
Eric A. Gurzell
Eric A. Gurzell PhD, high education andragogy.
References
- Dietary Supplement Health and Education Act. (1994). In. S. United States of America.
- Federal Food, Drug, and Cosmetic Act. (1938). In. United States of America.
- Academy for Teaching and Learning. (2023). Summative assessment. Baylor University. Retrieved June 16, from https://www.baylor.edu/atl/index.php?id=965148.
- Avery, R. J., Eisenberg, M. D., & Cantor, J. H. (2017). An examination of structure-function claims in dietary supplement advertising in the U.S.: 2003-2009. Preventive Medicine, 97, 1–10. https://doi.org/10.1016/j.ypmed.2017.01.008
- Balasubramanian, A., Thirumavalavan, N., Srivatsav, A., Yu, J., Lipshultz, L. I., & Pastuszak, A. W. (2019). Testosterone imposters: An analysis of popular online testosterone boosting supplements. The Journal of Sexual Medicine, 16(2), 203–212. https://doi.org/10.1016/j.jsxm.2018.12.008
- Becker, T. B., Lucas, J., Li, W., & Fenton, J. I. (2020). Redesign and process of reforming an existing undergraduate Nutritional Sciences program. Advances in Physiology Education, 44(4), 570–578. https://doi.org/10.1152/advan.00029.2020
- Bonafede, M., Caron, W., & Zeolla, M. (2009). An evidence-based elective on dietary supplements. American Journal of Pharmaceutical Education, 73(5), 80. https://doi.org/10.5688/aj730580
- Commission., Federal Trade. (2022). Health products compliance guidance, edited by Federal Trade Commission. Federal Trade Commission.
- Committee on Evaluation of the Presumptive Disability Decision-Making Process for Veterans. (2008). Improving the presumptive disability decision-making process for veterans, edited by J. M. Samet and C.C Bodurow. The National Academies Press.
- Cowan, A. E., Tooze, J. A., Gahche, J. J., Eicher-Miller, H. A., Guenther, P. M., Dwyer, J. T., Potischman, N., Bhadra, A., Carroll, R. J., & Bailey, R. L. (2023). Trends in overall and micronutrient-containing dietary supplement use in US adults and children, NHANES 2007-2018. The Journal of Nutrition, 152(12), 2789–2801. https://doi.org/10.1093/jn/nxac168
- Daher, J., Mallick, M., & El Khoury, D. (2022). Prevalence of dietary supplement use among athletes worldwide: A scoping review. Nutrients, 14(19), 4109. https://doi.org/10.3390/nu14194109
- Duarte, A. C., Spiazzi, B. F., Merello, E. N., Amazarray, C. R., Sulzbach de Andrade, L., Socal, M. P., Trujillo, A. J., Brietzke, E., Colpani, V., & Gerchman, F. (2022). Misinformation in nutrition through the case of coconut oil: An online before-and-after study. Nutrition, Metabolism, and Cardiovascular Diseases: NMCD, 32(6), 1375–1384. https://doi.org/10.1016/j.numecd.2022.02.002
- Fink, J., Schoenfeld, B. J., & Nakazato, K. (2018). The role of hormones in muscle hypertrophy. The Physician and Sportsmedicine, 46(1), 129–134. https://doi.org/10.1080/00913847.2018.1406778
- Garthe, I., & Maughan, R. J. (2018). Athletes and supplements: Prevalence and perspectives. International Journal of Sport Nutrition and Exercise Metabolism, 28(2), 126–138. https://doi.org/10.1123/ijsnem.2017-0429
- Gropper, S. S., Smith, J. L., & Carr, T. P. (2018). Advanced nutrition and human metabolism (7th ed.). Cengage Learning.
- Islam, M. A. (2013). An elective course on the basic and clinical sciences aspects of vitamins and minerals. American Journal of Pharmaceutical Education, 77(1), 17. https://doi.org/10.5688/ajpe77117
- Johnson, S. B., Park, H. S., Gross, C. P., & Yu, J. B. (2018). Use of alternative medicine for cancer and its impact on survival. Journal of the National Cancer Institute, 110(1), 121–124. https://doi.org/10.1093/jnci/djx145
- Kibble, J. D. (2017). Best practices in summative assessment. Advances in Physiology Education, 41(1), 110–119. https://doi.org/10.1152/advan.00116.2016
- Marra, M. V., & Bailey, R. L. (2018). Position of the academy of nutrition and dietetics: Micronutrient supplementation. Journal of the Academy of Nutrition and Dietetics, 118(11), 2162–2173. https://doi.org/10.1016/j.jand.2018.07.022
- Mikulic, M. (2023). Total U.S. dietary supplements market size 2016-2024 (in billion U.S. dollars). Statista. Retrieved February 7, from https://www.statista.com/statistics/828481/total-dietary-supplements-market-size-in-the-us/.
- Navarro, V. J., Barnhart, H., Bonkovsky, H. L., Davern, T., Fontana, R. J., Grant, L., Reddy, K. R., Seeff, L. B., Serrano, J., Sherker, A. H., Stolz, A., Talwalkar, J., Vega, M., & Vuppalanchi, R. (2014). Liver injury from herbals and dietary supplements in the U.S. Drug-Induced Liver Injury Network. Hepatology (Baltimore, Md.), 60(4), 1399–1408. https://doi.org/10.1002/hep.27317
- Pascale, B., Steele, C., Attipoe, S., OʼConnor, F. G., & Deuster, P. A. (2016). Dietary supplements: Knowledge and adverse event reporting among American Medical Society for sports medicine physicians. Clinical Journal of Sport Medicine: Official Journal of the Canadian Academy of Sport Medicine, 26(2), 139–144. https://doi.org/10.1097/jsm.0000000000000213
- Temple, N. J. (2022). A rational definition for functional foods: A perspective. Frontiers in Nutrition, 9, 957516. https://doi.org/10.3389/fnut.2022.957516
- Thomas, D. T., Erdman, K. A., & Burke, L. M. (2016). Position of the academy of nutrition and dietetics, dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance. Journal of the Academy of Nutrition and Dietetics, 116(3), 501–528. https://doi.org/10.1016/j.jand.2015.12.006
- Tucker, J., Fischer, T., Upjohn, L., Mazzera, D., & Kumar, M. (2018). Unapproved pharmaceutical ingredients included in dietary supplements associated with us food and drug administration warnings. JAMA Network Open, 1(6), e183337. https://doi.org/10.1001/jamanetworkopen.2018.3337
- Van Thuyne, W., Van Eenoo, P., & Delbeke, F. T. (2006). Nutritional supplements: prevalence of use and contamination with doping agents. Nutrition Research Reviews, 19(1), 147–158. https://doi.org/10.1079/NRR2006122
- Wallace, T. C., MacKay, D., Al-Mondhiry, R., Nguyen, H., & Griffiths, J. C. (2013). Dietary supplement regulation in the United States. Springer International Publishing. https://search.ebscohost.com/login.aspx?direct=true&db=cat09276a&AN=ebc.ebs2261928e&site=eds-live.
- White, C. M. (2022). Continued risk of dietary supplements adulterated with approved and unapproved drugs: Assessment of the US food and drug administration’s tainted supplements database 2007 through 2021. Journal of Clinical Pharmacology, 62(8), 928–934. https://doi.org/10.1002/jcph.2046
- Whiting, S. J. (1994). Safety of some calcium supplements questioned. Nutrition Reviews, 52(3), 95–97. https://doi.org/10.1111/j.1753-4887.1994.tb01396.x
- Wiggins, G., & McTighe, J. (2005). Understanding by design (2nd ed.). Association for Supervision and Curriculum Development. [Database].