Undergraduates’ knowledge, attitudes, and behaviours associated with fad diets

ABSTRACT

Purpose

We aimed to determine undergraduate students’ use and knowledge of fad diets as well as examine how appealing students found these diets given the goal of rapid weight loss and/or improved health. Twenty-three students from a Midwestern university (mean age = 19.2, mean BMI = 27.35, 69.6% female) were recruited through new student orientations for this qualitative study. Approximately 52% of participants identified as White, 30% as Black, 13% as Asian, and 4% as multi-racial.

Methods

Knowledge and opinions about fad diets were collected via focus groups and individual interviews. Coding of transcripts was conducted by hand using the constant comparative method and data were analysed based on grounded theory.

Results

Two primary themes emerged: very negative views of fad diets and the importance of healthy eating. Although few participants had tried fad diets, they thought these diets: 1) did not lead to sustained weight loss, 2) were associated with disappointment and health issues, and 3) were money-making schemes delivered heavily through social media. Participants also valued healthy eating.

Conclusion

Experimental studies are needed to examine how healthy eating among university students can be supported through credible sources, accurate information, and established connections via innovative social media platforms.

KEYWORDS:

• Fad diets
• college students
• overweight
• social media
• healthy eating
• qualitative

Attending college is a major transition period in the lives of many young adults, and it is during this time that they become increasingly independent in their dietary choices (Stok et al., 2018). Vilaro et al. (2018) found that food choice preferences in college students were linked to three factors that included: 1) price of food, 2) “busy daily life and preferences” (e.g., convenience and taste), and 3) “healthy aesthetic.” Sogari et al. (2018) found meal planning; food knowledge and preparation; and physical activity were associated with healthy eating among college students. On the contrary, barriers to healthy eating for these college students included time constraints, readily available foods with high caloric content, and the expensive cost of healthy foods. Sogari et al. (2018) also demonstrated that many students perceived the transition to college to be stressful and that their time was more limited as compared to high school, both of which contributed to unhealthy habits.

An unhealthy lifestyle (e.g., poor diet, low physical activity, high sedentary leisure) puts people at risk of becoming overweight and excess weight is significantly associated with life-threatening diseases (e.g., cardiovascular disease [CVD], type 2 diabetes, and some cancers; Hutfless et al., 2013; Tahreem et al., 2022). Although diseases such as CVD are likely to show up later in life, excess weight in college students should not be ignored. Young adults who are struggling with excess weight at the level of overweight or obesity are significantly more likely to move to an even higher BMI category compared to any other age group in adulthood (Katsoulis et al., 2021). Gaining just 1/2–1 pound per year beginning in young adulthood is very problematic in regards to the future development of obesity, and associated premature death, likely from CVD or type 2 diabetes (Hutfless et al., 2013).

Many fad diets promise rapid weight loss with minimal effort, which could make them appealing for college students who are busy and do not think they have time to exercise, for example (Khawandanah & Tewfik, 2016). Busy college students might also believe that a fad diet will easily provide them with better health (Anderson, 2023). Most fad diets involve adjusting the amount of protein, fat, and carbohydrates in various combinations such as in the case of the Atkins Diet or Zone Diet, whereas other fad diets fixate on a specific food item such as the Grapefruit Diet or Cabbage Soup Diet (Khawandanah & Tewfik, 2016). Fad diets are typically extreme and do not provide a nutrient balanced diet (Khawandanah & Tewfik, 2016). They usually do not include physical activity recommendations and are not typically maintained over one’s lifespan (Tahreem et al., 2022). The 2012 National Health Interview Survey showed that 7.5% of Americans have used one or more “special diets” over the course of their lifetime which included the vegetarian diet, Atkins diet, macrobiotic diet, Pritikin diet, or Ornish diet, and that most of the people who used these diets were college educated (Leung et al., 2018). A recent systematic review found that examining college students’ use of fad diets is a neglected area of study (Spadine & Patterson, 2022). Therefore, the purpose of the current study was to determine if students were using fad diets as well as investigating their knowledge and attitudes about these diets.

Materials and methods

The study was reviewed and approved through expedited procedures by the IRB at Oakland University (Rochester, MI, USA; IRB#1438073). Oakland University has some on-campus housing (e.g., residence halls, apartments), but it is largely a commuter campus. The only criteria necessary for study participation were current enrolment as an undergraduate student at the university and being 18 years of age or older. Participants were primarily recruited over the course of approximately 5 months through a database of students who attended a new student orientation and expressed an interest in being contacted about future Psychology Department research studies. Participants were also recruited via campus flyers during the first month of recruitment. Students from the database were sent an email with information about the study, the inclusion criteria, and the amount of compensation they would receive if they participated. Also contained in this email was a link to a SignUpGenius with preset dates and times available for registration. Those who learned about the study via campus flyers were instructed to send an email to the second author, who would then send them the previously described information and the SignUpGenius link. Students were able to see the number of spots remaining for each date but could not see the names of other participants.

Potential participants arrived for their scheduled focus group session on campus. When only one participant showed for a focus group, an individual interview was conducted because we did not want to send anyone home without collecting data from them. Therefore, we conducted five focus groups (each group had 3–4 participants) and five individual interviews. Upon arrival, participants first completed the informed consent process which involved reading the consent form, having any questions answered, and signing two copies of the consent form. Each participant took one consent form home and a second consent form was filed in a locked filing cabinet located in the third author’s office. Participants had their height and weight measured using a Doran DS5100 digital physician’s scale. Body mass index (BMI) was calculated via the following equation: weight in pounds/height in inches² x 703. Next, they completed a demographics questionnaire created by the authors which contained basic demographic questions such as race, class standing, and major. The primary author has been conducting qualitative studies for over 10 years. Therefore, the primary author served as lead moderator of the focus groups and was assisted by the other two authors. A list of ground rules was provided at the start of each focus group, which included such items as defining confidentiality, the plan for the focus group, and the reason for recording the session. We also requested that participants be as honest as possible so that we would have accurate information for data analysis. An IRB-approved list of questions was used (Table I). The IRB also approved the use of follow-up questions to allow for exploration of topics brought up by participants. The follow-up questions were also used to reduce the possibility of making assumptions during coding about what participants meant during the interview. Participants were provided with a $15 Amazon gift card upon completion of the study.

Table I. IRB-approved list of questions.

1. Are there any foods you typically try to avoid in your diet? Why? 2. What resources, if any, does the university provide to make healthy nutritional choices? 3. When you hear fad diet, what comes to mind? How do you feel about them? Why do you feel that way? 4. What are the names of some fad diets? 5. How did you learn about fad diets? What do you know about them? 6. Have you, a friend, or relative ever tried a fad diet? If yes, what was the reason for trying one? 7. What are the perceived benefits and drawbacks of fad diets?

Focus groups and individual interviews were audio-recorded and the second author took notes as a back-up and to help facilitate the creation of accurate transcripts. The second author along with two undergraduate research assistants created and checked each transcript. Data were analysed based on grounded theory, which is an inductive approach that allows for the identification of themes, and possibly a core theme or theory (Braun & Clarke, 2006; Corbin & Strauss, 2014; B. Glaser & Strauss, 1967). Coding was conducted by hand using the constant comparative method for generating themes (B. G. Glaser, 1965). Every step of the coding process was led by the first author who was joined by the second and third authors. As all three authors participated in both data collection and coding, a model called data saturation was used to determine when data collection was complete, that is, no additional focus group interviews would be conducted. According to Saunders et al., there are four possible models to determine saturation (Saunders et al., 2018). Data saturation is based on examining “ … the degree to which new data repeat what was expressed in previous data” during data collection (Saunders et al., 2018). Saturation occurred in the current study after 23 students had participated in focus groups or individual interviews. All three authors independently read each transcript, looking for possible themes and identifying relevant quotes. A meeting was held after each independent transcript review to discuss the work of each coder. A theme list and a document with relevant text were edited over the course of the discussions with the purpose of creating a final list of themes, subthemes, and quotes based on a consensus of all three authors. All transcripts were reviewed again by the primary author to ensure the final theme list and relevant quotes were accurate and complete (Miles & Huberman, 1994).

Results

Demographic characteristics

Twenty-three undergraduate students (Mean age = 19.2, Mean BMI = 27.35) participated in the study; 69.6% were female, 21.7% were male, and 8.7% chose not to respond. In regards to class standing, 47.9% were Freshmen, 21.7% were Sophomores, 21.7% were Juniors, and 8.7% were Seniors or Post-baccalaureate. Approximately 52% were White, 30% were Black, 13% were Asian, and 4% were multi-racial. None of the participants were Hispanic or Latino/Latina. Over 65% of the sample had a job and none of the participants were college athletes. Approximately 69% of the sample had a major related to science or health (e.g., biology, nursing, pre-med, psychology, health sciences).

Qualitative findings

The analysis of the qualitative data did not lead to a theory; however, two main themes emerged. First, participants held very negative attitudes about fad diets. Participants believed that fad diets were not beneficial for sustained weight loss, were associated with physical health issues and disappointment, and were thought of as money-making schemes via a heavy social media presence in the lives of young people. Second, participants believed in the importance of healthy eating. They clearly understood what healthy eating was all about and regularly avoided certain foods they perceived to be unhealthy. The themes, subthemes, and some representative quotes are described in detail below.

Negative attitudes about fad diets

Fad diets are problematic

Many participants had an extremely negative view of fad diets even though very few participants had actually tried one. They stated that fad diets are attractive because people want a quick and easy way to lose weight. However, fad diets do not work for everyone. If they do provide weight loss, then the weight will be gained back, which will lead to disappointment.

Yeah, I just don’t think they’re very effective. I think, even if you lose weight, it won’t stay off. Once you stop that, you’re gonna gain it right back and obviously it’s not something you can continue to do because your body needs a whole range of nutrients and minerals. If you’re not supplying it with all that, it’s not helping you in any way except maybe your appearance but you’re still not prolonging your life. You’re just damaging yourself on the inside for something you want on the outside. [Participant 5]

I think false hope. We discussed that fad diets are mainly a quick fix, like you think you’re gonna drop like 10 pounds within 2 weeks or something extreme like that, but I think it leads to false hope because you believe it’s finally going to be the thing to help you lose weight or makes you feel better about yourself, and it’s shown don’t really work and that they’re not going to give you that change that you’re really longing for, so I guess you could call it a false diet instead of a fad diet, just because it’s not going to give you the results you’re really looking for. [Participant 1]

Some participants associated fad diets with feeling “defeated” or having lowered self-confidence if the diets do not work.

It can really hurt your self-confidence or you’ll get stuck in that place and if you don’t stick with the diet then you feel kind of depressed about it. I don’t have any personal experience, but that’s what my personal opinion is. [Participant 11]

Participants stated that fad diets are not sustainable because they are extreme, you can’t eat what you normally like to eat, and some diets are not “real food.” Some participants talked about the negative impact of fad diets on physical health such as insomnia, muscle wasting, low energy, and dehydration due to the use of diuretics and laxatives.

Fad diets are a money-making scheme

Participants frequently talked about the business aspect of fad diets, which they viewed as a way for celebrities and influencers to make money.

… I think they’re considered influencers, because they’re basically just regular people paid to advertise stuff. [Participant 19]

In a weird way, there’s sort of like a joke aspect to them [fad diets], because I feel like a lot of people see through them pretty quickly, like after they first come out, and there’s sort of that buzz about them, like people sort of realize that, oh this is just a scam. [Participant 9]

Some participants were doubtful that these individuals used the products they were endorsing.

Uh, they sort of become that because, especially the teas and the juices, they have celebrities promote them but like, it’s very obvious the celebrity doesn’t use them, so it’s like so ridiculous. [Participant 9]

Social media is a strong influence

Social media is the place where many participants learned about fad diets, with Instagram being mentioned most often as the platform in which fad diet information was provided.

Instagram for me. I see a lot of ads for dietary supplements, and fad diets, and things like that. Instagram is the big one for me. [Participant 13]

The first thing that pops into my mind is it’s like, I forgot what it’s called, like the Skinny Tea or something like that, like on Instagram. If you drink this tea, you’re going to lose all this weight, but it’s pretty much just a major diuretic, like there’s nothing that special to it … [Participant 1]

Other social media platforms mentioned by participants included YouTube, Twitter, Snapchat, Facebook, Pinterest, and Tumblr. Participants primarily thought social media influences were problematic.

Oh man, let me tell you. Social media is a blessing and it’s a curse … And when you follow certain people on social media with certain body types that you could see yourself having, it puts yourself in an unrealistic position, because a lot of those people fail to see that the people on the screen and in the photo and stuff like that, they may have possibly had work done to get that way. [Participant 20]

However, a few participants spoke about one positive aspect of social media; that is, they viewed healthcare professionals (e.g., nutritionists, exercise experts, physicians) as credible sources of information about healthy living.

Other exposures to fad diets

After social media, participants were exposed to fad diets through other individuals in their lives. For example, one or more family members (primarily a parent) informed some participants about fad diets and/or were influential in regards to what participants ate.

Basically because my mother basically taught me to stick to your origins and things that are proven and well known and don’t stick to things on the internet and stuff like that, basically. [Participant 10]

Weight loss was the primary reason family members were trying fad diets. The Keto diet was reported to have been used most often by family members; however, participants also frequently mentioned the Paleo diet and intermittent fasting. The Mediterranean diet, Whole30, Weight Watchers, the Atkins diet, and the South Beach diet were all mentioned, but less frequently than Keto, Paleo, and intermittent fasting.

My mother has tried Keto [for weight loss]. It didn’t really fit her, she lasted probably a month and that’s it. My father did intermittent fasting. It worked for him for a little while and then he fell off it. [Participant 23]

Some participants spoke about friends trying or informing them about fad diets.

… I had a friend who actually going into nutrition in college right now and he has tried to get me into Keto and I really wasn’t all for that. [Participant 21]

Lastly, a small number of participants mentioned learning about fad diets through a school health class.

Healthy eating is important

Defining healthy eating

Many participants explained that fad diets are contrary to healthy eating which involves consuming nutritious foods (i.e., high fibre, protein). Healthy eating also means moderation, which was described as limiting unhealthy foods that are high in sugar or fat, for example. Some participants said that it is acceptable to enjoy unhealthy foods they love as long as it is only once in a while.

So, what I think a healthy diet is basically what’s good for you and what’s in proportions. Like you can have all the greens you want, you can have all the vegetables in your system, you can also have a ton of junk food in your system. But they can cancel each other out if you’re not proportioning correctly. So, you don’t have to give up the things you love to have a healthy relationship with your body. You can always have junk food, like I tend to, once a week or once every two weeks, I’ll get myself pizza as a reward with how I’m doing in my classes or things like that. But I have to take it in proportion, I love pizza I could eat it every single day, but I know my body can’t eat that every single day and be able to process it, so I’m trying to proportion it out. [Participant 16]

Some participants shared ideas of how to eat healthy such as filling a plate with vegetables first before other foods, substituting unhealthy foods for healthier options (e.g., using almond milk instead of cow milk), and preparing meals in advance.

Commonly avoided foods

Participants identified “unhealthy” food items that they tried to regularly avoid, with the most commonly avoided foods described as being oily, greasy, or fried. These foods are often found at fast food establishments, and were described as “gross,” hard to digest, and not tasting as good as home-cooked meals.

A personal decision. Well that, and it’s mixed with, like in my community, how heart problems are a huge thing. It’s mostly from fried foods and pig feet and obscure meats, so I try to stay away from that. [Participant 20]

Some participants were trying to reduce their sugar consumption (e.g., cutting down on drinking sugar-sweetened soft drinks, which participants called “pop”).

… I try to find like pop that doesn’t have as much calories and just like not drink as much. I always try to substitute water out if I can. [Participant 16]

Some participants stated that they avoided processed foods because these foods are higher in calories, low in nutritional value, and/or contain chemicals or non-natural ingredients.

… A Dorito, you look at that thing and you’re like where does this even come from. You wouldn’t know unless you looked at the ingredients list. You know, I just think it’s weird and your body wasn’t made for that. Society made that, not nature. [Participant 5]

Finally, some participants were trying to avoid caffeinated beverages because they were concerned about the amount of caffeine they were consuming.

Discussion

The purpose of this study was to determine college students’ knowledge, attitudes, and behaviours regarding fad diets. First, participants in this study presented very negative attitudes about fad diets, even though most had never tried them, including that fad diets 1) were not beneficial for sustained weight loss; 2) were associated with physical health issues; 3) could create disappointment if weight loss does not happen or the weight is gained back; and 4) were schemes that had a strong presence on social media which included targeted marketing to college aged students. Second, college student participants in this study recognized the importance of good nutrition and its direct link to their overall health. Specifically, they easily identified what “healthy” eating choices were and stated that they regularly avoided certain foods that they considered “unhealthy.” These findings are of interest because they are in contrast to reports from other previously published studies in which nutrition knowledge was not found to be linked with healthy eating behaviours in college students (Abraham et al., 2018; Deliens et al., 2014). There is always the risk of social desirability bias in qualitative studies, given the highly interactive nature of this research modality. Social desirability bias occurs when participants present themselves in a more favourable way than they truly are currently (Bispo Júnior, 2022). However, we used some recommended strategies to minimize the possibility of social desirability bias while collecting our data (Bispo Júnior, 2022). First, we emphasized the confidential nature of our study during the consent process and when reviewing the ground rules before the focus groups. Second, all participants were instructed to be as honest as possible in order for us to obtain accurate information for data analysis. Third, the primary author created a warm, welcoming, and relaxing interview environment as usual. Finally, as the goals of this study were to find out student use, knowledge, and attitudes about fad diets, we never provided our own knowledge or attitudes about fad diets. We asked the questions listed in Table I, and these questions were intentionally written not reflect our opinions, but rather elicit participants’ opinions (e.g., When you hear fad diet, what comes to mind? How do you feel about them? Why do you feel that way? What are the perceived benefits and drawbacks of fad diets?). The more likely explanations for our findings are the strong influence and importance of the health beliefs and the concerns with health maintenance that the college student participants in this study expressed.

A strong presence of fad diet marketing on social media was identified by our participants. They indicated that this marketing did not influence their health behaviours (with the exception of “credible” sources), but for many it did contribute to negative beliefs about fad diets. This finding is of particular interest because 84% of Pew survey respondents, ages 18–29, reported using social media platforms (e.g., YouTube, Facebook, Instagram, and Snapchat) in 2021 (Pew Research Center, 2021). Additionally, a large percentage of this age group uses social media every day (e.g., over 70% of Instagram or Snapchat users; Pew Research Center, 2021). At this level of exposure, it would be anticipated that this type of marketing would have had a strong influence on the use of fad diets, yet we did not see this outcome in our participants. Of note, these types of social media platforms often promote “thinness” as the ideal body image. It would have also been anticipated that the college student participants in this study would have been vulnerable to this type of targeted messaging because their average BMI classified them in the overweight category, even though we did not specifically recruit on the basis of BMI. Our participants were not influenced to use fad diets for weight loss. At this time, we can only speculate that this lack of influence may be due to their health beliefs regarding nutrition and the importance of maintaining their health. Further research is needed to better understand the specific influence of social media on healthy eating, particularly because social media has typically been one aspect of multi-component interventions (Chau et al., 2018). Existing studies have often used social media to encourage socialization among research participants rather than leveraging existing social media connections to bolster engagement and maintenance of behaviour change (Chau et al., 2018). Finally, the efficacy or effectiveness of innovative social media platforms (e.g., platforms that allow the uploading of photographs such as Instagram) on healthy eating behaviours have yet to be examined (Chau et al., 2018).

Family and friends trying to lose weight were also identified as sources of exposure to fad diet information, and although social engagement and support from these groups are usually seen as very influential, the participants in this study were not persuaded to try fad diets for weight loss (Wang et al., 2014). Reasons for the lack of influence by social support groups are not clear at this time, but the lack of influence may also be linked to the participants’ focus on eating healthy foods to maintain their health and/or using healthier weight loss strategies (e.g., consuming less calories) as described previously.

This study had some strengths. First, a common way to recruit participants for studies of this nature is through the use of flyers. We used some flyers to recruit for the current study; however, our primary recruitment method was to select names from an existing database of students who had attended a new student orientation session over the past several years and extend an invitation for them to participate in the study. The use of flyers and a database both involved volunteers, but the latter method allowed for the possibility of a more diverse sample in regards to race as 30% of our sample were Black, 13% were Asian, and 4% were multi-racial. Second, the use of focus groups provides rich data because the interactions among participants allowed for confirmation of themes.

Like all studies, this study also had some limitations. First, we only had 23 students participate in the study. However, data saturation was met, making it unlikely that the inclusion of additional participants would have made a difference in the information we obtained. Second, this study was conducted in the Midwest on a university campus with a majority of commuting students; therefore, the findings from this study might not be relevant to students attending universities in other regions of the country or at universities where most students reside on campus. The findings might have been different among young adults who are not receiving a university education. We did not collect data regarding where our participants resided but under half of the participants had a university meal plan. Third, we did not ask participants to complete a food diary or administer a 24-hour food recall over multiple days, which could have allowed us to better characterize the current comprehensive eating patterns of the participants in this study. Finally, although we did measure height and weight to calculate the BMI of our participants, we did not collect data on past weight loss efforts or participants’ perception of their body image. Collecting these data could have allowed us to better characterize if the participants’ body weight or body image were associated with their perceptions of fad diets, healthy eating, or health risks.

Conclusion

The college student participants in this study indicated that they were not influenced to try fad diets by the targeted messaging on social media because of their health beliefs associated with the importance of healthy eating to achieve positive health outcomes.  Harnessing the potential of social media to encourage and support healthy eating in young adults is a next logical step.  Credible sources and information seem essential given the findings of the current study.  Further research is needed to investigate the influence of social media on healthy eating in university students by leveraging existing social media connections on innovative social media platforms.

Acknowledgments

Thank you to Erica Cogswell and Sofia Osorio-Martinez for creating and checking transcripts.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was supported by the Embark program at the Oakland University William Beaumont School of Medicine.

Notes on contributors

Andrea T. Kozak

Andrea T. Kozak is an Associate Professor in the Department of Psychology. She teaches and mentors psychology undergraduate and graduate students. Dr. Kozak’s research primarily centers around investigating factors that contribute to excess weight (low distress tolerance, dysfunctional eating patterns, poor sleep, stress); studying innovative ways to reduce weight and keep it off (e.g., tech behavioral health interventions); and examining the consequences of overweight and obesity (e.g., poor health-related quality of life, chronic diseases). She has expertise in both qualitative and quantitative research designs.

Noah Garber

Noah Garber is completing his medical degree from the Oakland University William Beaumont School of Medicine.

Virginia Uhley

Virginia Uhley is an Associate Professor in the Department of Foundational Medical Studies and Family Medicine & Community Health. She is responsible for the development, integration, and assessment of the longitudinal nutrition curriculum (M1-M4). Dr. Uhley’s research focuses on the role of nutrition on the prevention and treatment of chronic diseases such as obesity, cancer, and diabetes. She is an expert in nutrition assessment methodology, measurement of clinical laboratory biomarkers associated with dietary intake, and medical nutrition therapy for obesity, diabetes, and cancer.