The other day, I was drinking a glass of wine with a friend of mine, and she mentioned a story that she recently read in Scientific American called "Changing Our DNA Through Mind Control." She was excited to tell me how scientists had found that decreasing your stress can actually change your DNA! This was fascinating! She was excited! I was excited! But being the scientist that I am, I wanted to understand what, how and why, so I needed more information. To gather this information, I looked at the original scientific article in the journal Cancer. (see here for my post on what a scientific article looks like).
The researchers had taken breast cancer patients and split them into two groups - one group went to mindful meditation classes and the second group did not. The scientists then took a sample of their DNA isolated from the patient's blood and tested the length of their chromosome's telomeres. To remind you, all people have 23 pairs of chromosomes in each and every cell. Telomeres are found at the ends of the chromosomes and protect the chromosomes from being damaged (essentially eaten away at from the ends by DNA-chomping proteins inside the cell). A common comparison is to think of telomeres like the plastic bits at the end of shoelaces. The shorter the telomeres (or the shorter the plastic bit), the closer the chromosome (or the shoelace) is to being damaged. In this study, the researchers found that the telomeres in cancer patients who went to meditation were longer than the patients that didn't. Because of this, their DNA was better protected. How incredible!
How unbelievable. Unbelievable for a few reasons:
- The researchers looked at the length of telomeres over a three month time span. Telomeres shorten over a lifetime, so I wouldn't expect to see a significant change over 3 months (whether sick, well, stressed, or not stressed).
- Because of this reasoning, I looked carefully at the data they presented in the paper. None of it was statistically significant. There is a trend that showed that patients that did not go to meditation were slightly, on average, a tiny bit lower than patients that went to mediation, but nothing that convinces me that what they are seeing is real, In fact, even the paper's authors said that if they wanted to have enough patients to get to statistical significance in the results, they would need to do a bigger study with more than double the number of participants.
- As a final nail in the coffin, in the psychological analysis comparing the mood of the meditating versus non-meditating patients, the researchers didn't notice a change in stress or mood scores. So even if there was a change in the DNA (which there isn't), since their mood doesn't change, a decrease in stress cannot be the cause of the telomere/DNA changes.
I'm not saying that mood doesn't have the ability to affect your DNA - maybe it does. I just don't think that they showed it in this study.
But I don't want to harp on these researchers or this study. In fact, here's another interesting example. A science journalist, Dr. John Bohannon, recently wrote a scientific article based on an actual study that they did studying people's diet and how chocolate contributed to their weight loss. They found that eating chocolate once a day significantly increased weight loss! The data was real, they published the results, and the media picked it up like wildfire. It was published by news media around the world!!! Only problem - the conclusions they they drew were crap, and Dr. Bohannon published them with the intention of baiting the media. In this case, there were too few participants, so they found something that was "statistically significant" in this group of people but wouldn't necessarily pan out if there was a full, well-designed study. John Bohannon wrote a great blog post about this whole experiment and why this is the case.
So what's the message here? I think the first is that the media often looks for science that can create a striking, head-turning headline. The problem is that when the conclusion is so cool, journalists don't always read the original article or evaluate the data to make sure that this cool headline is supported by evidence in the publication. To be fair, journalists may assume that since other scientists already reviewed the paper for scientific accuracy (a process called "peer review") that it will be good to go. But just because a stranger hands you a drink in a bar and says its okay, should you just believe them that it doesn't contain Roofies? I also don't want to imply that all science journalism falls into this trap, but with ever shortening deadlines and competition for the "hot headline," I can only imagine how appealing it is to take shortcuts.
To conclude, I actually have a problem in writing this post in that I don't have a solution for you, my reader. Unlike the friend I was having drinks with, you may not have a scientist at your beck and call to vet all news stories for scientific accuracy. And as much as I hope that this blog is helping you to obtain your own PhD in biology, you won't have all the tools you need to evaluate scientific articles on your own. So maybe I will leave you with a tried an true saying "Don't believe everything you read" or maybe "If it sounds too good to be true..." it might be.
I'm not the only person who has written about this topic. If you're interesting in reading more, check out this article from NPR, numerous articles from Ben Goldacre about how science is misrepresented in the media compiled on Bad Science, and a different point of view, an article published in Salon about how just because someone is a scientist doesn't mean that they are an expert (especially if they are on Fox News).
Dr. Cathy Seiler is the Program Manager for the tissue biorepository at St. Joseph's Hospital and Barrow Neurological Institute. She has her BA in Biochemistry and Molecular Biology from Boston University and PhD in the Biological Sciences from Cold Spring Harbor Laboratory. Her research and teaching focuses on genetics, cancer, and personalized medicine. Find her on Facebook at www.facebook.com/thingsitellmymom