Twins show genes may play a role in body image
October 3rd, 2012
12:01 AM ET

Twins show genes may play a role in body image

Blame for a teen’s unhealthy body image often falls on the media. The barrage of size-zero supermodels and waif-like celebrities walking the red carpet could push anyone to curse their shape, right?

A study published this week in the International Journal of Eating Disorders finds a new culprit may also be partially to blame: Our genes.

Researchers wondered why only a small percentage of the population developed an eating disorder when everyone was being exposed to the same images. They hypothesized that certain genes could make a person more or less prone to accepting the “thin ideal.”

The study

Lead author Jessica Suisman, a clinical psychology graduate student at Michigan State University, and her colleagues analyzed data from 343 female twins aged 12 to 22 years old.

More than half of the twins were identical; 138 were fraternal. Identical twins share all of their genes, while fraternal twins only share 50%.

Each twin was asked nine questions from a standard body image questionnaire that determined the degree to which they wanted to look like various media personalities.

The researchers also examined the environmental factors that the twins shared (their parents, their school) and the factors they didn’t share (different friend groups, extracurricular activities, etc).

The results

Identical twins were significantly more likely to have similar scores on the questionnaire than fraternal twins, suggesting genetics play a role in determining whether or not we will strive to look like the celebrities we admire.

“This sort of design doesn’t tell us which genes (are involved),” Suisman said. “We do know that there isn’t a single gene for thin-ideal internalization. It’s small effects from numerous genes.”

The researchers also found that shared environmental factors had little influence on the twins. In other words, sharing a house didn’t mean the twins would have similar views on body image.

Going forward

Suisman hopes to take a closer look in the future at what might be “underpinning” the genetic effects they found.

Personality traits are often decided by genes, she says, and may play a part in determining who’s more likely to develop an eating disorder. For instance, other studies have suggested perfectionism could lead to an unhealthy body image.

soundoff (18 Responses)
  1. MM

    I'm a fraternal twin and I'm reasonably sure we have different views of our bodies because we look different.

    Two people who look the same are going to be getting the same feedback from the people around them when it comes to their appearance. Two people who look different will be hearing different things and getting different cues. It's pretty common sense.

    October 3, 2012 at 12:45 | Report abuse | Reply
    • RedinAustin

      That's exactly what I was thinking. Fraternal twins share the same amount of DNA as any two non-twin siblings and can have appearances that are very different. If they look different, they could have radically different self images.

      October 3, 2012 at 13:47 | Report abuse |
    • Michelle Petrulsky

      That was a waste of a study. People who look alike feel the same way about their appearance. People who don't, don't. Duhhh!

      October 6, 2012 at 18:52 | Report abuse |
  2. SS

    My sister and I are fraternal twins with different height and foot size. However our faces look exactly alike. We have minor bone size and shape differences and as we are now 61 years of age we have gone through the different tastes,likes and activities over the years and are now back to looking much more like twins as we did when we were kids wearing matching dresses. Its interesting that with menopause my body shape has adjusted back to being near her body composition you could say. There have been many times where we have sent each other the same card in the same week or called each other at the same time. In clothes we are completely different ! When I saw this article I had to read it. Being a twin is so fasinating. I would truely miss my sis and my best friend.

    October 3, 2012 at 21:52 | Report abuse | Reply
  3. epona41

    how do you get 343 twins? think about it. 343.

    October 3, 2012 at 22:03 | Report abuse | Reply
    • Nicole

      I think they mean 343 sets of twins. But yeah......

      October 3, 2012 at 23:13 | Report abuse |
  4. epona41

    I'd also look for more info from this study ... how many were raised in separate homes, etc. Nine questions isn't a lot to go on. Although I have to say I've felt for a long time that the "happy" people were more likely a genetic group than an environmental group. I think that certain families just don't have it. And I don't think that it is purely because of socio economic factors.

    October 3, 2012 at 22:06 | Report abuse | Reply
  5. dharmendra maurya

    No comment

    October 4, 2012 at 08:18 | Report abuse | Reply
  6. dharmendra maurya

    I love you

    October 4, 2012 at 08:19 | Report abuse | Reply
  7. dharmendra maurya

    Very beautiful

    October 4, 2012 at 08:20 | Report abuse | Reply
  8. dharmendra maurya


    October 4, 2012 at 08:21 | Report abuse | Reply
  9. dharmendra maurya


    October 4, 2012 at 08:24 | Report abuse | Reply
  10. kcorker

    A few things to note about studies of this type: researchers who look at these questions are interested in the differences in outcomes that are attributable to shared genes (known as A effects) vs. shared environment (known as C effects) vs. unique environments (and error; known as E effects). Fraternal twins and identical twins both share some aspects of their environments (e.g., their homes and schools – this is the C effect), but they also have unique aspects of their environments (e.g., they may have different teachers at school or different friends – this is the E effect). As noted by other commenters, fraternal twins also look different so they may experience their environment differently because of this. This type of unique experience would be incorporated into the E component of the study. What the results of this study show is that susceptibility to eating disorders depends on A effects (genes) and unique environments (E effects), but not C effects (shared environment). Also it could be either 343 pairs or 343 twins – you don't have to have both twins in a set to do this type of research if you use modern methods of handling missing data.

    October 4, 2012 at 11:59 | Report abuse | Reply
  11. asdfasdf

    Honestly, this could be a factor on weight, but people, you get fat because of the choices you make. Also parents play a big role in kids health. If you're an irresponsible parent and don't know how to take care of your kid of course they're not gonna have a great life, and they'll probably end up unhealthy and overweight. We can't blame the media and our genes for the level of physical fitness we have, because that choice is made, it doesn't come because you have a twin.

    October 5, 2012 at 06:36 | Report abuse | Reply
  12. pjincvl

    Identical twins were significantly more likely to have similar scores on the questionnaire than fraternal twins, suggesting genetics play a role in determining whether or not we will strive to look like the celebrities we admire. I don't get it????

    October 5, 2012 at 14:44 | Report abuse | Reply
  13. Jennifer

    This is sort of off the subject but I used to get a kick out of the studies where the subjects were "identical twins raised apart". I always wondered where/how they found so many!

    October 8, 2012 at 19:45 | Report abuse | Reply
  14. Alison

    I'm an identical, seventeen year old twin girl and everyone saying that peeople who look alike will have the same body image is ridiculous. Just because you look alike doesn't mean you feel the same way about yourself; my sister and I, for instance, both had issues with body image (I developed anorexia and she developed EDNOS) but we were insecure about very different parts of our body, which I think is important to note.

    January 6, 2013 at 15:34 | Report abuse | Reply
  15. Lynelle Klaass

    There are basically five types of body shapes or figures each with its perfect bikini wear. These are the apple, hourglass, pear, rectangular and round shapes. The apple shape is characterized by a fuller upper body and smaller lower body unlike the pear shape which is the exact opposite. Rectangular bodies have an athletic structure with a small chest and a typically skinny frame all round. The hour glass figure is assumed to be the easiest to dress a bikini since women with this shape have a perfectly defined waist. The round shape women have a lot of weight in the tummy and not a well defined waist. The amazing thing is that each of these women has a bikini type that will make them stand out..

    Look at the best and newest posting at our personal web portal

    February 11, 2013 at 03:37 | Report abuse | Reply

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