Despite the fact every conceivable media outlet for the last fifty years has been forcing the notion down our collective throats that being thin is the most important thing in the universe, when it comes to endometriosis being thin is apparently not the preferred body model of choice. There have been several studies that suggest women with a lower BMI are more at risk of developing endometriosis than those with a higher BMI.
BMI, I should clarify, stands for Body Mass Index, essentially a ratio of weight to height that is often (mistakenly) used as a measure of overall health, but more on that later. Having a BMI of:
Less than 18 means you are underweight
Between 18 and 25 means you are of normal size
Between 25 and 30 means you are overweight
Over 30 means you are obese
Over 40 means you are morbidly obese
Anything over 50 and you will probably receive a personal visit from Richard Simmons.
Firstly, a Korean study, published only a year ago, looked at women with minimal and mild endometriosis and women with advanced endometriosis. It turned out that women with advanced endometriosis had a significantly lower BMI than those with minimal/mild disease. You may think then that being thin is bad, but looking at the details, that is not necessarily the case. The average BMI for women in this study with minimal disease was 23.0, the average BMI for women with severe disease was 21.4. Both of these groups of women fell well within the ‘normal’ BMI bracket meaning that neither group could be considered under or over weight. Also this particular study did not include a control group (i.e. a group of disease free women) to compare with women with endometriosis, which widens the margin for error.
Another study, this time from Italy in 2005, looked at the differences in BMI between women with and without surgically confirmed endometriosis. This study concluded, much like the Korean study, that women with endometriosis were significantly taller and weighed less than controls. So does this mean that women with endometriosis are spindly giants, wandering the countryside like elfin goddesses? Well not quite, sorry. The average height for women in the control group was 162.4cm (about 5 foot 4), the average height for the women with endometriosis was 164.5cm (about 5 foot 5). The average weight of the control group was 58.8Kg (129.4 pounds), the average weight of women with endo was 57.2Kg (125.8 pounds). Not that much different I think you’ll agree. But I did say the results were significantly different. The trouble is I meant mathematically significant, which is simply the product of several very long statistical calculations that may not appear significant in general terms. Confusing? Yes, but also necessary.
The next two studies both come from the USA, albeit one from May 2010 and one from Nov 2005. These two studies again both concluded that women with endometriosis tended to be slimmer and taller than controls (although not by much in real terms). However, these studies concluded that having a leaner body shape during adolescence and young adulthood increased the likelihood of developing endometriosis regardless of adult body habitus and menstrual characteristics. So does that mean we should all force feed pies to our children? Well, no because as one author points out “That women diagnosed with endometriosis may have a consistently lean physique during adolescence and young adulthood lends support to the suggestion of there being an in utero or early childhood origin for endometriosis”. Meaning that being thin during early life and having endometriosis go hand in hand. Essentially being thin doesn’t cause endometriosis, endometriosis causes you to be thin (when you’re young anyway). Why might this be the case? Perhaps the genetic or causes for endometriosis, whatever they may be, bring along other changes such as changes to metabolism which may lead to leaner body shape during childhood.
You’ll notice that most of these studies use BMI as a measure for weight. Therefore, you may think having a high BMI means you're fat. However that is simply not the case (up to a point). A body builder, for example, may have the same BMI as an obese person, because BMI is not an accurate measure of body fat, it is only a ratio of height to weight. So it should be worth noting next time you read a story connecting endometriosis to body weight whether they use BMI or body fat as a variable, it could make all the difference.
Although it would appear changing your diet cannot stop you from developing endometriosis, some changes may result in symptomatic relief. For more information on diet and endometriosis I recommend you check out Dian Mills’ book ‘A Key to Healing through Nutrition’.