Investigation of lifestyle choices of individuals following a vegan diet for health and ethical reasons

Investigation of lifestyle choices of individuals following a vegan diet for health and ethical reasons

Accepted Manuscript Title: Investigation of lifestyle choices of individuals following a vegan diet for health and ethical reasons Author: Cynthia Rad...

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Accepted Manuscript Title: Investigation of lifestyle choices of individuals following a vegan diet for health and ethical reasons Author: Cynthia Radnitz, Bonnie Beezhold, Julie DiMatteo PII: DOI: Reference:

S0195-6663(15)00073-2 http://dx.doi.org/doi:10.1016/j.appet.2015.02.026 APPET 2456

To appear in:

Appetite

Received date: Accepted date:

30-12-2014 19-2-2015

Please cite this article as: Cynthia Radnitz, Bonnie Beezhold, Julie DiMatteo, Investigation of lifestyle choices of individuals following a vegan diet for health and ethical reasons, Appetite (2015), http://dx.doi.org/doi:10.1016/j.appet.2015.02.026. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

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Investigation of lifestyle choices of individuals following a vegan diet for health and ethical reasons

Cynthia Radnitza*, Bonnie Beezholdb, and Julie DiMatteoa

a

School of Psychology, Fairleigh Dickinson University, 1000 River Rd., Teaneck, NJ 07666, USA b Department of Nutrition, Benedictine University, 5200 College Drive, Lisle, IL 60532, USA

* Corresponding author Email address: [email protected], Acknowledgements: The authors would like to acknowledge the assistance of Carol Burtnack, Maria DiNello, Michael Greenberg, Michelle Herrera, Cassandra Hoy, Tyler Loranger, Bret Moyer, Amy Rinne, and Melissa Sharp. Key Words: Ethical vegan, health vegan, vegetarian, health behaviors, lifestyle, vegan, nutrition

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Abstract The proportion of individuals choosing to follow a vegan diet has increased in recent years. The choice is made for different reasons, primarily concern for animals (ethics) and health, which may impact both specific food choices and other lifestyle behaviors linked to health outcomes. To determine the extent to which the reason for following a vegan diet was associated with health behaviors, we conducted an online survey recruiting an international sample of 246 individuals who reported adhering to a vegan diet. We hypothesized that compared to those following the diet for ethical reasons, those doing so for health reasons would consume foods with higher nutritional value and engage in other healthier lifestyle behaviors. Our hypotheses were partially supported in that those citing health reasons (n=45) reported eating more fruit (U=3503.00, p=0.02) and fewer sweets (U=3347.00, p<0.01) than did those citing ethical reasons (n=201). Individuals endorsing ethical reasons reported being on the diet longer (U=3137.00, p<0.01), and more frequent consumption of soy (U=2936.00, p<0.01), foods rich in vitamin D (U=3441.00, p=0.01), high-polyphenol beverages (U=3124.50, p<0.01), and vitamin supplements (vitamin D: χ2=4.65, p=0.04; vitamin B12: χ2=4.46, p=0.03) than did those endorsing health reasons. As these factors may affect outcome in studies investigating the impact of vegan diets on health, they should be taken into account when studying persons following a vegan diet.

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Introduction The proportion of Americans following a vegan diet has increased substantially in the past 15 years from approximately 300,000 to 500,000 people in 1997 to between 2.5 and 6 million in 2012 (1-2% of the U.S. population; Newport, 2012; Stahler, 2012). The number of vegans worldwide has yet to be established, although research indicates that this number is on the rise, especially in more affluent countries (Key, Appleby, & Rosell, 2006). For example, a recent survey in Israel reported that 5% of Israelis consumed a vegan diet (Aharoni, 2014). In a survey of 3,618 individuals in the United Kingdom, 2% self-identified as vegan (Department for Environment, Food and Rural Affairs, 2007), while in another survey of Australians, 1% reported following a vegan diet (The Vegetarian/Vegan Society of Queensland Incorporated (VVSQ), 2013). In Germany there are 900,000 vegans, approximately 1% of the population (VEBU, 2014). Surprisingly, India, which has a large number of vegetarians (31%; Yadav & Kumar, 2006) has a relatively small number of vegans. Moreover, in early 2014, Google Trends reported the highest level of searches for the term ‘vegan’ (100 on scale of 0-100; Google Trends, 2014). One reason for this interest in a vegan diet is its reported health benefits. There have been several studies documenting the nutritional and health status of vegans (Craig, 2009; Dwyer, 1988; Key et al., 2006). In a cross-sectional study, vegans were found to have an average body mass index (BMI) of 23.6 compared to non-vegans who had a mean BMI of 28.8 (Tonstad, Butler, Yan, & Fraser, 2009); a BMI 22.5 to 25 is considered ideal (Mahan & Escott-Stump, 2000). Similarly, vegans are found to have lower cholesterol (Bradbury et al., 2013), and blood pressure (Pettersen, Anousheh, Fan, Jaceldo-Siegl, & Fraser, 2012), as well as reduced risk of cardiovascular disease (Spencer, Appleby, Davey, & Key, 2003) and diabetes (Tonstad et al., 2013a). Both vegan and vegetarian diets may lower the risk of certain cancers such as colon (Fraser, 1999), stomach (Key et al., 2009a), female (Tantamango-Bartley, Jaceldo-Siegl, Fan, & Fraser, 2012), and prostate (Fraser, 1999) cancers. Risk of diverticular disease for vegans was only a quarter of that of omnivores (Crowe, Appleby, Allen & Key, 2011) while risk for hypothyroidism was 10% lower than omnivore risk (Tonstad, Nathan, Oda & Fraser, 2013b). In the Adventist study (Orlich et al., 2013), the largest study of the health effects of vegetarian and vegan diets, the overall death rate for vegans was reduced 15%, which approached statistical significance. However, in other studies with smaller samples (e.g. Burr & Sweetnam, 1982; Key et al., 1998; Key et al., 2009b) there was no survival advantage for those following a vegan diet. While reduced mortality has not yet been shown for the vegan diet, it is clear that substantial health benefits may accrue to those adhering to it. Foods consumed on a vegan diet are diverse and not always healthful. They can include fruits, vegetables, legumes, nuts, seeds, healthy fats, and whole grains, with documented health advantages (Key et al., 2006; Spencer et al., 2003). At the same time, grain-based foods high in sugar, salt and unhealthy fats can be vegan. This raises the question of whether the health advantages of a vegan diet result from just avoiding animal products, or from an overall concern for health that includes choosing nutritious

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foods and engaging in other health-promoting behaviors. In fact, if choosing a vegan diet is linked to engaging in healthier behaviors overall, then these factors should be investigated and accounted for in future studies. Other researchers have noted that people following a vegan diet may choose to do so for different reasons, which in turn, may affect their food and lifestyle choices (Dyett, Sabaté, Haddad, Rajaram & Shavlik, 2013). These reasons include health, animas rights (ethics), environmental concern, influence of others, and sensory disgust, with health and ethical considerations emerging as the most often cited reasons. Both quantitative and qualitative research has shown that health and ethical reasons were most often cited for choosing to follow a vegan diet (Dyett et al., 2013; Ruby, 2012) In the current study, our objective was to investigate reasons for choosing a vegan diet and associations with a wide range of health and lifestyle factors in a large international sample of individuals following a vegan diet. We hypothesized that those choosing a vegan diet for health reasons would be more likely to engage in other healthy behaviors, which could affect their health and nutritional status. Materials and Methods Participants. Participants were solicited through events targeting vegans (e.g. festivals and social gatherings) or through social media (e.g. Facebook groups). To be included, participants had to affirm that they were between the ages of 25 and 60, and that they consumed a strictly vegan diet as indicated by answering “none” to a multiple-choice question asking which animal foods they consumed at least monthly. Three hundred fourteen individuals began the survey, and 302 finished it, with complete data available for 246 individuals. Participants were excluded from data analyses if they were under age 25 or over age 60, if they indicated they had a debilitating chronic disease, or if they reported consuming animal foods at least monthly or took a fish oil supplement. Recruitment notices described participation in a study examining diet and lifestyle factors. For those interested, a link accessed an online survey delivered by SurveyMonkey® where they reviewed an IRB-approved informed consent form before completing the survey questions. Measures. To assess the reason for following a vegan diet, a survey question asked participants to rank order their motivations for choosing their diet pattern, selecting their primary reason from several options including religious beliefs, health benefits, family influences, ethical concerns (animal rights), environmental reasons, sensory disgust, weight loss, introduction in early childhood, or other. Other survey questions asked about health behaviors, specifically cigarette smoking (yes/no), alcohol intake (number of standard drinks consumed weekly), sleep (average number of hours per night), exercise (number of times they engaged in moderate and strenuous exercise per week) (Godin & Shephard, 1985), work (average number of hours spent in work or schoolwork each week), prescription medication (checked if taken for allergies, anemia, anxiety, low mood, ADD, menstrual or GI), and supplement use. Participants also indicated whether

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they had engaged in the following mind-body practices in the past week: yoga, tai chi, qi gong, Pilates, or meditation. Participants also completed the Depression Anxiety Stress Scales-21 (DASS; Crawford & Henry, 2003), a brief measure of three negative affective states (depression, anxiety, and stress). The social support variable was derived from the Multidimensional Perceived Social Support Scale (Zimet, Dahlem, Zimet & Farley, 1988). To reduce the respondent burden of an extensive survey, we chose three questions representative of each of the support domains: family, friends, and significant others. Responses indicating the level of agreement on a 7-point Likert scale were summed to create a composite social support measure. For specific diet questions, we focused on foods that have been shown to have health benefits (e.g. soy, omega-3 fatty acids, vitamin D, and fruits and vegetables; Anderson, Smith, & Washnock, 1999; Liu, 2003) or harmful effects (e.g. sugary soda, sweets; Hu & Malik, 2010). We also focused on foods high in polyphenols as these phytochemicals are particularly beneficial due to their antioxidant and anti-inflammatory bioactivity (Arts& Hollman, 2005). We used standard medium portion sizes from the USDA database (see Supplemental Table). Participants were asked questions adapted from the EPIC-Oxford study (Spencer et al., 2003). Specifically, they recorded estimated average daily intakes of fruits, vegetables (excluding potatoes and corn), and sweets. They also recorded monthly intakes of plant sources of vitamin D (fortified milk substitutes + button mushrooms), as well as the following select foods that are among the highest in polyphenol content (Pérez-Jiménez, Neveu, Vos, & Scalbert, 2010): soy (miso + soy flour + soybeans + soy yogurt + soy milk + tempeh + tofu), fruits (apple + blackberries + blueberries + cherries + dark plum + dried fruit + grapes + raspberries + strawberries), juices (grapefruit juice + apple juice + blueberry juice + pomegranate juice), fruits and juices (total fruits + total juices), beverages (total juices + teas + coffee + cocoa + red wine), high omega-3 plant foods (canola oil + flaxseed oil + flaxseeds + chia seeds + walnuts), and high omega-6 plant foods (corn oil + grapeseed oil + safflower oil + sunflower oil ). Results Data were analyzed using nonparametric statistical tests due to unequal sample sizes. Mann-Whitney U tests were conducted to compare those following a vegan diet for ethical (ETH) and Health (HEA) reasons on diet duration, DASS-21 scores, BMI, exercise patterns, hours worked per week, hours spent outdoors per week, sleep, social support, alcohol intake, and food consumption patterns. Effect size was calculated for significant variables using Pearson’s r. Chi-square analyses were conducted to compare participants on supplement intake, medication use, being on a weight-reducing diet, engagement in mind-body practice, and cigarette smoking. Cramer’s V was then calculated as a measure of effect size for significant variables.

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Health benefits (n=45) or ethical concerns (n=201) were, by far, the most often cited reasons for choosing the vegan diet. The sample was predominantly female, with the majority of individuals reporting Caucasian descent (see Table 1 for demographic data). Almost two thirds were from the U.S. There was no significant difference between groups in BMI. The majority of participants were normal weight (60.43%), 6.38% were underweight while 24.26% of the sample reported a BMI in the overweight range, and 8.94% were obese. HEA reported less stress (numerically) as measured by the DASS-S subscale compared to ETH, however, the difference was not significant (see Table 2). ETH also reported a significantly longer duration on the diet than did HEA (U = 3137.00, p < 0.01). No other significant differences were obtained for non-diet related lifestyle comparisons analyzed using Mann-Whitney U tests. Mann-Whitney U Tests were conducted for the ETH and HEA groups to compare the frequency with which they consumed certain categories of foods (see Table 3). ETH reported consuming soy-based foods (U=2936.00, p<0.01), foods high in vitamin D (U=3441.00, p=0.01), and select beverages high in polyphenols (U=3124.50, p<0.01) more frequently per month, whereas HEA consumed select fruits and fruit juice more frequently per month (U=3556.00, p=0.03) and select fruits more frequently per day (U=3503.00, p=0.02). ETH also reported significantly greater consumption of sweets per day (U=3347.00, p<0.01) compared to HEA. There was a trend for ETH to consume more alcohol standard drinks per week compared to HEA and for HEA to consume more vegetables per day compared to ETH; however, these tests were not significant (see Table 3). Pearson’s r statistics were calculated for significant findings yielding a small effect size for all significant findings (Cohen, 1992). We calculated Chi square statistics for the ETH and HEA samples (see Table 4) on measures of weight-reducing diet practices, cigarette smoking, mind-body practices, and medication and supplement ingestion, and found that ETH reported a significantly higher likelihood of taking a multivitamin (p < 0.01), a supplement (p < 0.01), a vitamin D supplement (p = 0.04), and a vitamin B12 supplement (p = 0.03). We calculated effect size estimates (see Table 4) for significant comparisons finding a small effect size for the multivitamin, vitamin D, and vitamin B12 supplement comparisons (based on guidelines established by Rea & Parker (1992) for interpreting Cramer’s V), and a moderate effect size for the supplement use comparison. Discussion To summarize, compared to the HEA group, the ETH group reported being on a vegan diet longer, consuming greater quantities of soy, select foods high in vitamin D, sweets per day, select beverages high in polyphenols and vitamin supplements. Conversely, the HEA sample reported consuming significantly more select fruits and fruit juices high in polyphenols than did the ETH sample. In our sample, the ETH participants had remained on the diet significantly longer than the HEA participants, a result consistent with that found by others (Hoffman, Stallings,

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Bessinger, & Brooks, 2013). Indeed, in a recent study (Asher et al., 2014) of both current and former vegetarians, a wider range of motivations for adopting a vegetarian diet were cited by current vegetarians, whereas the only reason for adopting the diet cited by a majority of the former vegetarians sampled was health concerns. In this study, 68% of current vegetarians cited animal protection as a reason for diet adoption versus only 27% of former vegetarians, a finding suggestive of a robust association between concern for animals and remaining vegetarian. There appears to be different trajectories for becoming vegetarian due to health and ethical reasons with both groups of vegetarians more likely to transition to veganism for ethical reasons (Jabs, Devine & Sobal, 1998). Those choosing a vegetarian diet for moral reasons reported greater disgust with meat and a more intense emotional reaction to meat consumption compared to those who became vegetarian for health reasons (Rozin, Markwith & Stoess, 1997). Consistent with the more intense emotional reaction to meat reported by Rozin et al. (1997) was our finding (approaching significance) that compared to the HEA group, the ETH group reported more overall stress. We can hypothesize that this more intense emotional reaction to meat might motivate a quicker transition to veganism, which may account for the finding of longer duration on the diet among those citing ethical reasons. As both the Jabs et al. (1998) and Rozin et al. (1997) studies are now almost twenty years old, we can speculate that the vegan transition may have been delayed in the health vegans. Or, the more recent dietary transition was possibly motivated by the publication of additional research showing the health benefits of the diet as well as the proliferation of meat and dairy substitutes (annual increases between 2 and 8 percent; Ginsberg, n.d.) and more vegan options in restaurants. Alternatively, the advent of these events may have attracted greater numbers of vegans choosing the diet for health reasons more recently. Large percentages of those choosing the diet for either reason tended to remain on it after 3 years (VRG; Mangels, Brathwaite, & Stahler, 2010), suggesting that once an initial time investment is made, the diet becomes well entrenched. Overall, we found a few notable significant differences in diet quality between the two samples, albeit with small effects. Although substantial health benefits have been noted for soy-based foods (Hu & Malik, 2010), other studies have cast doubt on their health value (e.g. Setchell, 1998; Siegel-Itzkovich, 2005). A recent review of the health effects of soy concluded that if minimally processed or fermented, there are likely beneficial effects including protection from cancer, heart disease, and symptoms of menopause (D’Adamo & Sahin, 2014). At the same time, as there are anti-nutrients and by-products (e.g. hexane) involved in forming highly processed soy, excessive consumption of these forms may have harmful effects. There is less controversy regarding the health advantages of fruits (Liu, 2003; Mohindra, Nicklas, O’Neil, Yang, & Berenson, 2009). Reviews of research have shown that they provide a wide variety of vitamins, minerals, phytochemicals and fibers (Liu, 2003), and that increased consumption is associated with health benefits, namely, reduced incidence of coronary heart disease, type 2 diabetes, and obesity (Slavin & Lloyd, 2012).

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Evidence for the health benefits of phytochemicals such as polyphenols has been accumulating during the past few decades (Manach, Scalbert, Morand, Rémésy, & Jiménez, 2004) as they have powerful properties that prevent chronic degenerative diseases such as cancer and heart disease via mechanisms such as antioxidant function. In our analyses, the ETH sample reported greater consumption of high polyphenol beverages than did the HEA sample, a finding that would seem to conflict with our hypothesis. However, our measure of beverages high in polyphenols was computed by summing monthly intake of juices, teas, coffee, cocoa and red wine. Although these drinks contain high levels of polyphenols, they also have high levels of other substances that are considered less healthy, for example, sugar (juices and cocoa), caffeine (coffee, tea, and cocoa) and alcohol (red wine). Consequently, our sample of health vegans may have chosen to consume lower levels of these beverages due to concern over consumption of these other less healthy compounds. In line with our hypothesis, we found that ethical vegans reported a greater intake of sweets than did health vegans. Although the Dyett et al. (2013) study reported that their vegan sample consumed moderate amounts of desserts and sugar, they did not report any comparisons between their health and ethical vegan samples. High sugar intake has been linked to a wide array of adverse health effects including obesity (Woodward-Lopez, Kao & Ritchie, 2011), type 2 diabetes (Greenwood et al., 2014), hypertension (Malik, Akram, Shetty, Malik, & Yanchou Njike, 2014), cardio-metabolic disease (Richelsen, 2013), and compromised oral health (Falco, 2001). In our sample, the mean intake of daily sweets was .69 of a serving for the ETH group and .53 for the HEA group, which is not excessive and probably not indicative of a significant health risk. We found that ETH were more likely to consume plant foods high in vitamin D and take vitamin D supplements than HEA, a finding contrary to what we hypothesized. To explain the supplement finding, it’s possible that individuals choosing a vegan diet for health reasons are more focused on obtaining required nutrients from foods, and therefore did not feel the need to use supplements. However, in this case, there would be an expectation that the vitamin D intake from foods for HEA would not be significantly lower than that of ETH. Dyett et al. (2013), also examined vitamin D intake in persons following a vegan diet for ethical and health reasons. However, they did not report any significant differences between the two groups, although the intake of both was inadequate. Vegan diets may be lower in vitamin D than omnivore diets (Craig & Mangels, 2009), so eating more foods rich in vitamin D and taking supplements could prevent a possible deficiency. In addition to vitamin D supplements, overall, ethical vegans were more likely to take supplements including multi-vitamins, and vitamin B12. As mentioned before, it is possible that health vegans, in pursuit of better health from food sources may have eschewed supplement intake, believing that plant foods were a better source of essential nutrients. However, vegan diets provide insufficient amounts of B12 (Craig & Mangels, 2009). Indicators of B12 deficiency (plasma methylmalonic acid, homocysteine and holotranscobalamin II) have shown that vegans have low levels of

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B12 (Key et al., 2006); however, relatively few report clinical symptoms (Antony, 2003). Nonetheless, taking supplements or consuming fortified foods (e.g. soymilk) would be important to prevent deficiency. We did not find a significant difference in BMI between the ETH and HEA group. However, in the Dyett et al. (2013) study there were more health than ethical vegans classified as overweight and obese. In our sample, the proportion of overweight or obese participants (33.5%) was numerically lower than in the general population in the U.S. (69%) and Canada (60.5%), where most of our sample resided (WHO, 2008). As research accumulates investigating how reasons for choosing a vegan diet impacts food choices and other health behaviors, we can begin to develop profiles of ETH and HEA sub-populations. However, any interpretation of this research must acknowledge a few caveats, namely, 1) that discrepancies among studies in how data are gathered (populations sampled, methods of data gathering, questions posed) affect their results, 2) that there are differences in how studies have grouped sub-samples, and 3) that only a few studies to date (including ours) have investigated this question. Nonetheless, collectively, these studies have demonstrated that compared to those choosing the diet for health reasons, those doing so for ethical reasons are more strict in doing so and have been eating this way for a longer period of time (Waldmann Koschizke, Leitzmann, & Hahn, 2003; present study). In addition, ethical vegans are more likely to consume high fat foods (Dyett et al., 2013), soy foods (present study), sweets (present study) high-polyphenol beverages (present study), vitamin D foods (present study) and supplements (present study), but less likely to eat fruits (present study). Also worth noting are the many non-significant findings in all of the published reports, which suggests that among those following a vegan diet, diet motivation may have only limited impact on food and other lifestyle choices. The interpretation of these results should be considered in light of a few limitations inherent in the design of the study and the survey method we employed. The majority of participants were ethical vegans. This should not be seen to reflect the proportion that actually chose the diet for ethical versus health reasons. We recruited a convenience sample and our recruitment methods may have impacted the number of individuals we obtained in each group. At the same time, the proportion of participants we obtained for each group is consistent with those found in some studies (e.g. Fox & Ward, 2007; Hoffman et al., 2013; Jabs et al., 1998) although others (e.g. Dyett et al., 2013; Waldmann et al., 2003;) obtained samples that were more equal. Nonetheless, across all studies, health benefits and concern for animals were the two most frequently cited reasons for choosing a vegan diet. Although participants were divided according to the primary reason for choosing the diet, other reasons may have also been important either initially, or over time when they became more aware of the full array of consequences for their chosen diet (Ruby, 2012). Also, in forming our variables, we attempted to use questions from validated measures (e.g. for social support), but in some cases either there were no validated measures for the lifestyle questions we wanted to ask or adding multi-item measures

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would have lengthened the survey too much. In several instances, we utilized single items to measure variables as studies have shown that single item measures with high face validity are valid when compared to multi-item scales (Abdel-Khalek, 2006; Dollinger & Malmquist, 2009). In the interest of reducing participant burden, we also did not use a complete food frequency questionnaire, but instead inquired about foods that research has shown were most predictive of health, either positively or negatively, such as fruits and sweets (Key et al., 2006; Parletta, Milte, & Meyer,, 2013; Spencer et al., 2003; Wahlqvist & Lee, 2006). Conclusions The substantial increase observed during the past few years in the number of individuals following a vegan diet in some locales may indicate that for a portion of the population we are approaching a historic transition point to veganism driven by greater awareness of animal abuse, accumulation of research demonstrating the health benefits of a vegan diet, and a substantial increase in the availability of meat and dairy substitutes. Consequently, understanding the health implications of how the diet is followed seems more important. Some of our findings supported our hypothesis that compared to those choosing the diet for ethical reasons, those choosing it for health reasons would make other healthier choices. The HEA group consumed more fruit and fewer sweets than the ETH group. On the other hand, the ETH group reported greater consumption of foods and supplements where the healthy option was not as obvious (e.g. soy, supplements) which may explain the seemingly contrary findings. Our results stand in contrast to those reported in the Dyett et al. (2013) article where the only difference in food consumption between health and ethical vegans was that ethical vegans reported significantly greater intake of high fat foods. At this point, there is little research into specific foods consumed on this diet; therefore, more studies are needed to further elucidate dietary differences between subgroups following a vegan diet as differences may affect health and nutrition outcomes.

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16 Age 37.78 (10.22) 35.11 (10.04) Gender Male 24 31 Female 77 69 Country US 60 71 Canada 9 4 Other 31 24 State/Province Western US 22 22 Midwestern US 13 31 Northeastern US 30 19 Southwestern US 10 6 Southeastern US 13 16 Eastern Canada 10 0 Western Canada 4 6 Marital Status Single 34 53 Married 33 33 Divorced 13 2 Widowed 1 0 Cohabitating 20 11 Ethnicity Hispanic 4 4 Black 0 4 American Indian/Alaska Native 1 0 White 91 77 Asian 0 2 Middle Eastern 1 0 Mixed 3 13 Education (Yrs. beyond high school) 4.48 (2.68) 4.91 (2.41) Note: Shown are means (SD) or percentage of participants. 688

Table 2. Lifestyle differences in ETH and HEA vegans ETH n M SD Diet duration (yrs.)* 244 8.01 8.18 DASS-21 Depression score 246 6.20 7.74 DASS-21 Anxiety score 246 3.21 4.14 DASS-21 Stress score 246 8.06 6.85 DASS-21 Total score 246 17.47 15.71 BMI 235 24.08 4.65 Moderate exercise/week 212 4.52 3.99 Strenuous exercise/week 203 2.20 2.19 Hours worked/week 243 35.22 34.31 Hours outdoors/week 242 10.85 10.70

HEA M SD 5.57 7.57 4.89 6.38 3.73 4.82 6.00 5.33 14.62 14.08 23.81 5.53 5.83 5.17 2.61 2.09 33.30 17.04 11.84 11.01

U 3137.00 4061.50 4187.00 3736.00 4010.50 3863.00 2716.50 2732.50 4373.00 4147.00

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17 Sleep (hours/night) 245 7.11 0.99 7.22 0.93 Social Support - Special person 245 5.41 2.04 4.82 1.96 Social Support - Emotional support 245 4.82 1.96 4.82 2.10 Social Support - Friends 244 5.24 1.68 5.31 1.94 Social Support - Composite 245 17.47 15.71 14.62 14.08 Notes: Actual values versus mean rank values shown. * indicates significance at the p≤0.01 level. r=-0.01 for diet duration. 689

Table 3. Differences in food and beverage intake in ETH and HEA vegans ETH HEA n M SD M SD Vegetables/day 246 3.20 1.70 3.76 2.00 Fruits/day** 245 2.76 2.03 3.69 2.66 Sweets/day* 244 0.69 0.82 0.53 1.24 Soda/day 245 1.46 1.03 1.34 0.78 Alcohol servings/week 240 2.79 4.56 1.56 2.20 Soy foods/month* 246 43.72 44.73 24.91 25.92 Vitamin D foods/month* 246 47.79 43.76 38.51 45.79 Fruits/month* 246 59.71 95.36 81.99 78.32 Juices/month 246 10.40 43.40 6.97 10.35 Fruit and juice/month** 246 70.11 131.98 88.96 83.47 Beverages/month* 246 90.96 88.18 55.16 49.96 High-poly food/month 246 28.44 56.23 26.11 26.31 Total High-poly/month 246 201.15 215.98 177.78 111.62 High omega-6/month 244 7.72 13.53 5.67 7.44 High omega-3/month 246 28.65 29.01 34.39 38.91

4211.00 4406.50 4454.00 4100.00 4130.50

U 3798.00 3503.00 3347.00 4244.00 3555.00 2936.00 3441.00 3409.00 4034.00 3556.00 3124.50 4460.00 4189.00 3972.50 4280.50

Notes: See methods for list of foods/beverages within combined variables. Actual values versus mean rank values shown. r=-0.01 for all significant variables. * indicates significance at the p≤0.01 level. **indicates significance at the p≤0.05 level. 690

Table 4. Supplement use, mind-body practice, smoking and dieting in ETH and HEA vegans ETH HEA Χ2 V Absent Present Absent Present -Weight-reducing diet (last year) 147 52 36 9 0.74 -Currently smokes 180 19 41 4 0.02 -Mind-body practice 119 80 26 18 0.01 Multivitamin use* 141 60 41 4 8.39 0.19 No supplement use* 165 36 27 18 10.47 0.21 -Alga supplement 176 25 43 2 2.40 -Psych supplement 200 1 44 1 1.36 Vit D supplement** 127 74 36 9 4.65 0.14 Vit B12 supplement** 73 128 24 21 4.46 0.14 * indicates significance at the p≤0.01 level. **indicates significance at the p≤0.05 level. Supplemental Table: Food & Beverage Data

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18 Foods & Beverages Oils and Spreads Canola Oil Corn Oil Grapeseed Oil Flaxseed Oil Earth Balance Safflower Oil Sunflower Oil Soy Foods Miso Soy Flour Soy Milk Soy Yogurt Soybeans/edamame Tempeh Tofu Fruits Apple Blackberries Blueberries Cherries Dark Plum Dried Fruit Black Grapes Red Raspberries Strawberries Other Foods Chia Seeds Flax Seeds Mushrooms, white Walnuts Beverages Coffee Cocoa Milk Alternative Milk Grapefruit Juice Apple Juice, unfiltered Blueberry Juice Pomegranate Juice Red Wine Soft drinks, sweetened Green Tea Black Tea Vegetables/day

Portion Size 1 Tablespoon 1 Tablespoon 1 Tablespoon 1 Tablespoon 1 Teaspoon 1 Tablespoon 1 Tablespoon 1 Tablespoon 1/4 Cup 1 Cup 1/2 Cup 1 Cup 1/4 Cup 1/2 Cup 1 Medium 1/2 Cup 1/2 Cup 1/2 Cup 1 Plum 1/4 Cup 1/2 Cup 1/2 Cup 1/2 Cup 1 Tablespoon 1 Tablespoon 4 Large 1/3 Cup 1 Cup 1 Cup 1 Cup 1 Cup 1 Cup 1/2 Cup 1/2 Cup 1/2 Cup 5 ounces 12 ounces 1 Cup 1 Cup 1 Cup raw or 1/2 Cup cooked

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19 Fruits/day 1 Fruit or Medium serving Sweets/day 1 Serving Note: Participants indicated the frequency each food or beverage was consumed during the last month unless otherwise noted. 691

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