It has taken me several weeks to post this reply, which Dr. Christakis sent almost immediately after I sent him my email (see previous entry entitled “An Email to Dr. Nicholas Christakis”). During this time I’ve had the opportunity to learn and think more about Dr. Christakis’ work, and was not shocked to discover that my knee jerk response to his NEJM article on the spread of obesity through social networks was premature. However, I was far from alone in this reaction.

He asked that I post his response verbatim:

Dear Ms. Gordon:

What I learned from my correspondence with Dr. Christakis and a review of some of his vast trove of publications was that what had originally motivated him to study how feelings/perceptions spread through social networks was his work with terminally ill patients, which served as his initiation into clinical medicine. Through his interactions with these patients and their families, he understandably became concerned with the feelings of the family members and how it affected them and their social networks in turn.

I was surprised that as a Sociologist, Dr. Christakis would have been taken aback at the overwhelming attention received by his obesity study. Surely he must have been aware of the hair trigger emotions surrounding obesity in our society. It then occurred to me that perhaps, due to his initiation by fire into what must be one of the most difficult fields a physician can choose (end-of-life care), his attempt to approach the spreading of emotions through social networks through mathematics and statistics took him a step back from what must have been a very potent emotional experience. I felt that there was a certain detachment in the quantitative work involved in these analyses.
When I posited this to him, he explained:

Dr. Christakis is not primarily studying the “obesity epidemic” but rather how social networks work.

In 2007, Dr. Nicholas Christakis, a medical sociologist at Harvard University, published a study in the New England Journal of Medicine on the effect of social networks on the prevalence of obesity. I recently came across this study online, through links in a post by a friend, and revisited the results of the study. You can view a 3-minute interview with Dr. Christakis about his study and findings here.

After watching this interview and looking over Dr. Christakis’ website, I composed this email to him:

Dear Dr. Christakis,

When your paper came out in NEJM in 2007, I was participating in a weight loss program at St. Luke’s (NYORC). I remember our group leader, Rich Weil, presenting your findings to us. From what I recall, he seemed to have no opinion on it one way or another, but I don’t really remember.

I participated in the group for 2.5 years, and left it this past summer in disgust. I had lost about 12 lbs during the first year, and gained it back over the course of that time. I started and ended at around 225 lbs. I’m a 5′5″ 45 year old female. I have repeatedly, over the course of my life, even as a little girl, tried to lose weight. I was maybe 10-20% overweight as a child and young adult, but once I hit my early 30s, I hit 200 lbs. for the first time. After reaching 225 for the first time, I joined Overeaters Anonymous and became “abstinent” (from all refined sugar, flour and wheat), and lost 60 lbs. I maintained my abstinence but still gained back about 10 lbs before falling off the wagon 5 years later and returning to 225. I repeated this same cycle, fell off the wagon again after 5 years, and again went up to 225. It was at this point that I said – ENOUGH.

I have a Ph.D. in Developmental and Molecular Biology from Einstein (2001), so I try to follow the basic science literature on obesity. I’m also very interested in sociology and the impact of scientific communications on society – something which attracted me to your research.

I just viewed, online, the 3 minute interview with you about your paper, and I must admit that your reported findings don’t sit well with me at all. I have always battled my weight but felt that I have always been surrounded by (and shamed by) thinner people. I would classify myself as middle class, from a middle class background. My mother was never obese – in fact, there was not one obese person on her side of the family, going back 3 generations. My Dad was overweight and his brother was obese for most of his adult life. I have one sister, 3 years younger than I (we share both parents and are not stepsisters), who has never had a weight problem. Most of my classmates, fellow students and colleagues throughout my life were thin.

I think the social pressure is very much the opposite of obese people influencing those closest to them to be obese – I think its very much the other way around. And this pressure does nothing except force obese people to try everything and anything to maintain completely unsustainable weight loss. Your reported findings vilify obese people, by implying that it is desirable to shun them to maintain ones health. Obese individuals in western society already carry a huge social burden of great shame. I don’t appreciate the implications of your findings one bit.

From a brief review of your website, I understand that you make heavy use of mathematical models to support your conclusions.  The current state of the economy should be much more than enough to demonstrate to you that the maxim “lies, damn lies, and statistics” has never been so relevant. You’re a sociologist – get out of your lab, your ivory tower, and talk to people on the ground, for G-d’s sake.

It will be interesting to see if Dr. Christakis responds to my email and what he has to say. If I do get a response, I will report the gist of it.