The New York Times health blog Well features this headline: “Mother’s Diet May Affect Daughter’s Puberty,” on top of a story about a new study that concludes what women eat during pregnancy and nursing may affect the age at which their daughters start puberty.
How do researchers know this? Because of rats.
The investigators, from the University of Auckland, fed pregnant rats a high-fat diet throughout pregnancy and lactation. Another group of rats received a regular diet of rat chow. After the baby rats were weaned, they also ate either regular chow or a high-fat diet.
The onset of puberty was much earlier in all the rats whose mothers ate a high-fat diet, regardless of whether the baby rats ate high-fat or regular diets.
The findings are important, writes Tara Parker-Pope, because “a girl’s age at first menstrual period may influence her lifelong health. An early first menstrual period, before the age of 12, is a risk factor for breast cancer, teenage depression, obesity and insulin resistance.”
Those are valid concerns, of course, but the study doesn’t offer enough information to support alarming pregnant women that their diets may be the cause of all these future problems. A number of commenters take issue with the study and its implications. See, for instance, #8:
This whole subject is complicated and there’s so much confounding data and studies – we barely have scratched the surface and hardly anybody really knows anything. It’s way to early to freak and decide to indulge in some mom-guilt. And besides, rats are not people. There’s so much more work to be done here.
Conclusion: moderation in all things. There are plenty of other reasons to eat healthy fats in moderation no matter who you are. There is no reason to curl up in a ball of guilt over what you ate while pregnant with your daughters. Just do the best you can and move on.
Or consider #9, which raises interesting environmental questions:
So what kind of fats were the rats eating? Animal fats sourced from livestock who are shot up with growth hormones? Or fats from animals and plants raised without hormones (and other endocrine disruptors like pesticides)? I think that would be an important distinction to make here.
Other readers express concern that mothers are being blamed — yet again. Parker-Pope responds to several commenters inline, such as here, when she writes, “Where did the issue of fault emerge? And why is everyone being so defensive about maternal health during pregnancy? It’s not about blame. I’ve never met a pregnant woman who wasn’t highly interested in her health and the health of her unborn baby.”
Overall it’s an interesting discussion, not only for the research itself, but also for the debate surrounding the role of the media in covering health studies — particularly when the data is limited and the value of the material shared is unproven — and the effect on women who already feel burdened with pressure and guilt.
Late last year, Parker-Pope took a different perspective. Writing about the “The Fertility Diet,” she expressed concern that “the hype” over the book by Harvard researchers would “end up helping couples or merely add to their emotional burden.”
OBOS Executive Director Judy Norsigian wrote a comment posted at Well in support of the research outlined in the book. Her comment describes the decision-making process during the development of “Our Bodies, Ourselves: Pregnancy and Birth,” and she notes that “there were some chapter reviewers who wanted us to tone down the clear benefits of breastfeeding so as to avoid the likelihood that some women might feel guilty because they could not or happened to choose not to breastfeed. (This could be for medical, social, or workplace-related reasons.) We were very careful about the language we used, but we believed it important to include ALL critically important information about the benefits of breastfeeding.”
Norsigian continues: “Hopefully, we can find better ways to support infertile couples so that guilty reactions will be minimized in the process of reading and utilizing information like that offered by ‘The Fertility Diet.’ Researchers like Willett, Skerrett and Chavarro are certainly not responsible for media distortions of their work, and they did credit earlier research by pioneers such as Rose Frisch. As earlier postings noted, they are offering approaches with minimal health risks and a range of potential health benefits.”
The issue of guilt also came up in conversation with colleagues recently after I mentioned seeing a CNN report suggesting that women who are exposed to high levels of stress during pregnancy have an increased chance of their babies developing allergies or asthma later in life. The scary way the study was presented almost ensured that any pregnant woman not already stressed soon will be.
In this case, the research included 315 expectant mothers and their infants (not rats), and other reports I read online featured more comprehensive information. In this HealthDay News story, one of the study’s authors, Rosalind Wright, M.D., an assistant professor of medicine at Brigham and Women’s Hospital and Harvard Medical School in Boston who focuses on the rise of chronic respiratory disease in both adults and children and the connection to psychosocial stressors, notes that longer-term research is needed:
Mothers filled out a questionnaire designed to assess their levels of stress in many different domains. Financial issues, home issues, community safety, relationship problems and medical issues were the most frequently reported negative events experienced by the mothers.
Dust mite exposure was also assessed using samples obtained from the pregnant women’s bedrooms. When the babies were born, a sample of cord blood was taken. After controlling the data to compensate for maternal age, race, smoking, education, history of allergy and asthma, the child’s gender and the season of birth, the researchers found that the number of negative domains — stressors — reported was associated with an increased risk of elevated IgE in the cord blood.
“A mom who had three or more negative events would have a 12 percent increased chance of having a baby with elevated cord blood IgE,” Peters said.
Wright pointed out that elevated IgE is “suggestive” of an increased risk of developing asthma and allergy later in life, but that the association isn’t clear-cut and likely depends on exposure to other risk factors. The researchers will be following these children until they’re 5 years old to see if they end up developing asthma and allergies later in life.
So there’s a lot of information to digest — and more still to learn — yet that won’t stop some media from reducing complicated research to simplistic headlines that leave women feeling more stressed than ever.