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Will The Real Vegetarian Please Stand Up? – Part 1

When my younger sister first told me she wanted to become a vegetarian, I was worried. My biggest fear was that she would, like I did, develop an eating disorder. In high-school, I didn’t eat meat for roughly 14 months, and though I can’t be sure now of what my reasons were at the time, in retrospect, I do think in large part it was just a convenient way to avoid yet another food group. It was a legitimate reason to restrict my intake.

But is there any evidence that this behaviour (becoming vegetarian as a convenient way to restrict intake) is common among individuals with eating disorders? What is the relationship between dietary restraint, eating disorder symptoms, and vegetarianism? Is vegetarianism a risk factor for developing an eating disorder or do eating disorders lead many to adopt a vegetarian diet as a socially acceptable excuse to avoid eating specific foods? And, is there a difference between vegetarians that do not engage in dietary restraint and do not display eating disorder symptomatology, and those that do?

Thus far it appears that the research in this area is both contradictory and filled with methodological problems:

  1. Researchers have found inconsistent results when evaluating the level of dietary restraint between omnivores and “vegetarians” (I’ll get to why I put this in quotes). Some found higher levels of restraint in vegetarians (Barr et al., 1994; Gilbody et al., 1999; Trautman et al., 2008; Worsley & Skryzpeic, 1998), others found the opposite (Curtis & Cormer, 2006; Janelle  & Barr, 1995) and yet others found no differences at all (Barr & Broughton, 2000; Fisak et al., 2006; Larsson et al., 2002). So, there is no real consensus.
  2. What’s more, a lot of these studies lumped vegetarians (ovo-, lacto-, and ovolacto-vegetarians) into one group, while others lumped semi-vegetarians (pesco-, pollo-, and pescopollo-vegetarians) and ovo-, lacto-, and ovolacto-vegetarians into one group. (You can read about what these mean here.)
  3. Finally, higher restraint scores in the vegetarian groups may not mean increased disordered eating behaviour but might just be a by-product of the question types. Of course they restrict their intake in a sense (they are cutting out a food group!) but it may not be maladaptive.

What about direct studies on whether or not vegetarianism is a precursor to eating disorders? Two studies evaluated this question and found that roughly half of the individuals in treatment for anorexia nervosa were “vegetarian” (in one study that just meant they didn’t eat red meat). Interestingly, the vast majority (~95%) began to adhere to a “vegetarian” diet only after the onset of their ED (Kadambari et al., 1986; O’Connor et al., 1987).

Wanting to improve on the previous studies, C. Alix Timko and colleagues set out to figure out whether there are differences between vegans, vegetarians, semi-vegetarians, and omnivores in attitudes towards food and health, and eating disorder symptomatology (study #1). They also wanted to further categorize the differences between omnivores and semi-vegetarians (study #2). I’ll write about study #1 here and cover study #2 in my next post.

They recruited participants through university psychology departments, flyers, and the internet. All participants were at least 18 years old. Table 1 shows the demographic information of each subgroup (%ages calculated from the total sample size in each group).

Timko et al - 2012 - Table 1 Adapted

The participants then had to complete a whole bunch of questionnaires to evaluate their eating patterns, self-esteem, dieting behaviours, emotional status (depression, anxiety, stress) and so on.

They also asked the participants what their reasons were for starting and continuing the vegetarian diet:

Timko et al - 2012 - Table 2 Adapted
REASONS FOR VEGETARIAN DIET

If you look at the table above, you’ll see that semi-vegetarians were more likely than vegetarians and vegans to start and continue the diet for primarily health, as opposed to ethical reasons (they had to pick one main reason).

EATING ATTITUDES TEST

Although there were no statistically significant differences on the EAT (Eating Attitudes Test)-26 test, which examines disordered eating, the numbers approached significance semi-vegetarians scored higher than vegetarians, followed by vegans and omnivores (semi-vegetarians>vegetarians>vegans>omnivores).

DRIVE FOR THINNESS

Interestingly, vegans and omnivores had higher scores than vegetarians and semi-vegetarians (vegans, omnivores>semi-vegetarians, vegetarians).

EATING RESTRAINT

Semi-vegetarians had higher levels of restraint than omnivores and vegans (semi-vegetarians>omnivores, vegans). Vegetarians were in the middle and did not differ from any of the groups.

MENTAL HEALTH

There were no differences in depression, anxiety or stress between the groups. And individuals reported similar levels of physical activity.

When the authors compared the differences between the aforementioned test scores between those who chose the vegetarian diet primarily for weight control reasons to those who did not, they did not find any differences in the levels of disordered eating.

The conclusions the authors drew from this data was that although the samples were all rather healthy, the semi-vegetarian group did exhibit more disordered eating patterns and disordered eating attitudes than any of the other groups. (But, don’t forget about the unexpected finding that vegans and omnivores had higher levels of the drive for thinness than the semi-vegetarian and vegetarian groups.)

The semi-vegetarians had a more disordered eating pattern as evidenced by higher levels of restraint, external eating, hedonic hunger, and avoidance of food cues. Although not significantly different, semi-vegetarians had higher EAT-26 total and diet scores than the other groups. In contrast, vegans and omnivores did have higher (and statistically equivalent) scores on the EDI-DFT [Eating Disorder Inventory, Drive for Thinness Subscale] than either vegetarians or semi-vegetarians.

All in all, this study suggests that previous findings which indicated that vegetarians engage in more disordered eating patterns might have been due to the fact that vegetarians and semi-vegetarians were grouped together. Timko and colleagues hypothesized that those findings might have been due to the relatively high proportion of semi-vegetarians included in the vegetarian groups. In this study, if participants said they were vegetarian but it later turned out they just cut out red meat, they would be put into the “omnivores” group, whereas in some other previous studies, these red-meat avoiding participants would be grouped under “vegetarians.” (Misleading, don’t you think?)

The authors do warn that these findings are preliminary and more research needs to be done to replicate these findings. This is particularly so because there were many comparisons made in this study (between each group and every other group for every test and test-subscale) that the chances of type I error (a false positive) are significant (Read about the problem with multiple comparisons here, or here). So, it will be important to replicate this study with planned comparisons. (I’m not a statistician, but if this confuses you, do ask me, I can explain it in simpler terms.)

I don’t know much about the proportion of females to males among vegetarians, but I do wonder if the researchers in this study analysed the questionnaire results from males and females separately, would they find anything interesting or significantly different between male and female responses? And is that difference, if it exists, due to a real difference in behaviours or attitudes, or a by-product of questions being interpreted differently by different genders?

The vegan and vegetarian groups were overwhelmingly composed of females in this study. Indeed, overall 3 out of every 4 participants were females. So, analysing the genders separately here would be difficult (the male groups would be too small), but I do think it is something to consider.

As mentioned above, this paper had two studies. I’ve reported on the first one in this post and I’ll report on the second one, which compared eating-related attitudes and behaviours between semi-vegetarians and omnivores in more detail, in the next post.

Oh yes, and getting back to my sister, she’s still a vegetarian (it is been a few years now), for primarily ethical and environmental reasons. And thankfully, she doesn’t have an eating disorder or any disordered eating behaviours (as far as I know, anyway).

Timko, C.A., Hormes, J,M., & Chubski, J. (2012). Will the real vegetarian please stand up? An investigation of dietary restraint and eating disorder symptoms in vegetarians versus non-vegetarians. Appetite, 58 (3), 982-90 PMID: 22343135

Written by Tetyana

Tetyana is the creator and manager of the SEDs blog. She has an MSc in Neuroscience from the University of Toronto. Tetyana is passionate about science communication and knowledge translation. To get in touch, use the ‘Contact’ form on the website.

Discussion

10 Responses to “Will The Real Vegetarian Please Stand Up? – Part 1”

  1. I thought it was notable to see that, in Table 1, vegans were the highest percentage of smokers (I probably thought it notable because veganism is supposed to be in part a “healthy” choice when it is common knowledge that smoking does not equal healthy by any means). But, then again, it just ties back into the 66% who said “ethical reasoning” fuel their dietary choices, not health…

    Interesting results! Thank you so much for this post! Looking forward to Part 2!

    Posted by Jenny | December 11, 2012, 5:21 PM
    • Wow, I missed that completely! Funny how that happens, I was re-making the tables and totally didn’t notice. But you are right, it probably does have to do with the fact that for many, ethical issues were the primary reasons for the decision.

      I think it would be cool to do a study (or for someone to do a study), where you take like a big sample of eating disorder patients and interview the ones that are vegetarian, semi-vegetarian or vegan prior to starting treatment, and then interview them after treatment, and then maybe a few year later after recovery. It would be interesting to see if people’s motivations for their dietary decisions change, and if they remain vegan/vegetarian or not (and the differences between those that do and don’t). I would love to see an interview-based study, because questionnaires are so limiting sometimes.

      I bet there will be people who start for ED reasons and drop it after/during recovery (and maybe first they would say they are doing it for health/ethical reasons/whatever, but in retrospect say they did as a legit way to restrict their intake). But I think there will also be people who might start for ED reasons, and continue for non-ED reasons after recovery. And of course many other options. That would be interesting to see.

      Anyway, thanks for you comment Jenny!

      Cheers,
      Tetyana

      Posted by Tetyana | December 11, 2012, 5:30 PM
      • I had an interesting experience where I became a vegetarian for ED reasons at a super young age, around 11 or 12 and stayed a vegetarian for a long time (~10 years) in various states of recovery/relapse/sickness. Then in my most recent relapse, I decided to start eating meat again…also for ED reasons. That whole time I “claimed” it was for ethical reasons…I’m sure I’m not alone in that.

        Now I’m a total carnivore though, I actually feel really depleted if I don’t have animal protein, regardless of however else I am doing with food.

        Also I totally noticed that vegans were more likely to smoke. Interesting…

        Posted by Gina | December 16, 2012, 12:43 PM
        • I don’t remember why I stopped eating meat. I’m sure it was for eating disorder reasons (but maybe not). If anything, personally, environmental reasons would be the main driver if I were to decide to do that. (I don’t really see the ethical issue with eating animals, I think there should be better and more regulations for how to treat them, etc.. but not in general, with eating animals.)

          I’m confused though – you decided to eat meat again or ED reasons? Do you mean decided not to?

          When I’ve relapsed later, I didn’t avoid meat. I avoided high-calorie foods, but I ate a lot of fruit, veg and protein. I never liked red meat anyway, so it wasn’t a problem avoiding it, but, I found I had to eat some protein (and I don’t like non-fish/meat protein sources, just for taste reasons).

          But I really was worried when my sister decided to become vegetarian if that was just her way of avoiding foods. But, thankfully, it is not true. She is a normal eater! (Yay!) It seems based on this and other data, that semi-vegetarians are most likely to have disordered eating/eating disorders, which makes sense to me.

          Like Jenny said, it makes sense if they (the vegans) are not eating meat for ethical reasons, not health reasons.

          Posted by Tetyana | December 16, 2012, 7:02 PM
        • This is EXACTLY my experience. I became vegetarian at 12 for ED reasons, stayed vegetarian until age 27, and then started eating meat again…also for ED reasons (because of reading too many paleo blogs–grains apparently make you fat).

          Posted by Eva | April 22, 2013, 2:02 PM
  2. ‘Indeed, overall 3 out of every 4 participants were males’
    typo.

    Posted by Sarah | December 11, 2012, 6:59 PM
  3. Nice post, Tetyana!

    Anna Bardone-Cone at UNC has done some interesting studies of individuals at various stages of ED treatment and their motivations for vegetarianism. Individuals w/ ED or history of ED are more likely to report that they are motivated to become vegetarian in order to control their weight.

    Here is an abstract: http://www.ncbi.nlm.nih.gov/pubmed/22818732

    I think being vegetarian can be fine during recovery, as long as people are honest with themselves about their motivations. Since this can be tough (and even confusing!) I often ask patients to think about whether they read any animal rights blogs, would be willing to eat a vegan cupcake, or would be OK with substituting a higher-calorie vegetarian meal for a lower-calorie meat one.

    Jenny

    Posted by Jennifer Thomas | December 20, 2012, 12:44 AM
    • Hi Jenny,

      Thanks for the comment! I actually have that study on my hard-drive, but I overlooked it! I’ll probably blog about it the next time I cover the topic. I have the (what I think is typical) habit of downloading way more papers I have time to read!

      “I think being vegetarian can be fine during recovery, as long as people are honest with themselves about their motivations. Since this can be tough (and even confusing!) I often ask patients to think about whether they read any animal rights blogs, would be willing to eat a vegan cupcake, or would be OK with substituting a higher-calorie vegetarian meal for a lower-calorie meat one.”

      Those are really good litmus-test questions!

      Though for me, it often wasn’t calories but food I ate. I felt okay eating 4 apples but not a frozen meal that was 1/2 the calories. Odd, but I know I’m not alone.

      Do you find a lot of your patients are vegetarian in your practice?

      Posted by Tetyana | December 22, 2012, 10:29 PM
  4. But you didn’t include reason like “I don’t like meat”, and this is m main reason. For me, veganism would be restrickting, deprivating something, I couldn’t be health vegan, But in my case vegetarianism and intuitive eating is almost the same. It has nothing to do with my disorder.

    Posted by Alex | February 25, 2013, 6:53 AM

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