Intuition v. Science, and What You Need to Know About Cycle Syncing
Intuition v. Science, and What You Need to Know About Cycle Syncing
Should you change what you eat based on your menstrual cycle? And is that part of intuitive eating? Plus, some thoughts on the relationship between intuition and science.
Thanks to everyone for the great feedback about last week’s essay! It was more personal than most of what I write here, so it felt a little vulnerable to share, and I’m so glad it seems to have resonated with many of you.
And it’s funny: when I included the roundup of some of our top pieces of 2023, I actually neglected to include our second-most-popular post, which was primarily a personal essay about the death of my husband’s grandmother. That post also included a timely Q&A and some other random bits, and I left it out of the roundup because I wasn’t sure quite what to make of it—I didn’t know exactly what about it people were responding to, or what themes it represented. It didn’t give me very clear data. But in light of the popularity of last week’s piece, it seems like maybe personal essays deserve a place on my list of things to do more of in 2024. Let me know if you agree!
This week I have another little essay for you, though it’s less personal this time: It’s about the perceived tension between intuition and science.
There is a personal element to it, in that this is something I’ve been thinking about for years, as someone who’s at once a proponent of science-based medicine, a critic of shoddy science, an intuitive eating dietitian, and a person with multiple chronic health conditions. How do these things coexist and inform each other? Are they in tension or conflict? These are questions I’ve asked myself often.
Now feels like a good time to write about them, given that our first two podcast episodes of the year are with intuitive-eating dietitians—Elyse Resch, the co-author of the original Intuitive Eating book and last week’s guest, and Leah Kern, an anti-diet RD and certified intuitive eating counselor (whose episode is available now for paid subscribers and comes out for free on Monday).
Certain corners of wellness culture posit a dichotomy between biomedical science and intuition: don’t trust your doctor, trust your gut. Diagnose yourself, get off your meds, “fix it with food.” Your body knows how to heal itself without Big Pharma getting involved. Science just hasn’t caught up with it—or the research is actively being suppressed.
At some level I can understand why this rhetoric exists, misleading as it is.
There are grave problems with the conventional healthcare system, where listening to your intuition truly can mean the difference between getting the right treatments and getting the run-around—or worse, far worse. If a doctor dismisses you and doesn’t take your concerns seriously, but you just have a nagging feeling that something is really wrong, trusting that instinct can be lifesaving.
Yet this notion that intuition is inherently opposed to science and medicine is a slippery slope. It makes us vulnerable to sales pitches for products and treatments that seem gentle and “natural,” even when they’re actually ineffective or deeply harmful. At the extremes, it can make us vulnerable to deadly behaviors: “Trust your gut and keep yourself safe by refusing masks, vaccines, cancer treatments.”
Intuition can be weaponized.
I used to say things like “intuitive eating, intuitive everything.” There’s literally an episode of my first podcast called that. But while I do think it’s helpful to tune into intuition around eating—and while I do think that can spill over into tuning into your intuition in other areas of life where it’s appropriate—I also think it’s dangerous to approach everything with intuition alone.
Just because you’re eating intuitively doesn’t mean you should also make all your health and wellness decisions intuitively, or all your life decisions intuitively, without also involving critical thinking. (I can tell you from personal experience that “intuitive investing” is not a reliable strategy if you don’t know much about investing in the first place!)
Maybe once you’ve developed some expertise in a given area, your intuition can guide you in the right direction—but intuition at its best functions like an educated guess, and the educated part of that equation is essential.
Intuitive eating is not about only trusting your instincts. It’s about integrating your inner and outer awareness and using that to make your decisions. It’s about tuning back into your instincts about hunger, fullness, satisfaction, and letting go of diet-and-wellness-culture beliefs that have interfered with those instincts—AND it also does involve some gentle awareness of nutrition, especially as it applies to helping you feel energized and satisfied by the foods you eat, and building meals and snacks that will aid in that effort.
I think intuitive eating works for many people because we’re all pretty well educated on things like our hunger, our fullness, what satisfies us, what makes us feel our best. We’ve been practicing multiple times a day for our entire lives! In a sense we are actually the leading experts on those things, because we’re the ones who live in our bodies. So intuitive eating works in a way that intuitive approaches to other areas of life where we have less expertise might not.
When it comes to what and when and how much to eat, the science is nowhere near settled. There are so many different diets and lifestyles that are recommended and in conflict, and when you look critically at the science behind them, it’s…not very compelling, to say the least.
There are serious limitations with nutrition research, including the fact that it’s almost impossible to get any good long-term data on diets. Randomized controlled trials (RCTs) in this field are incredibly expensive and hard to pull off, because it’s impossible to truly control what people are eating unless you keep them in a facility for the duration of the study. And yet RCTs are the gold standard of research, the only method that can tell if a particular intervention is more effective than a placebo.
Instead, nutrition studies are overwhelmingly observational, which means they can only tell us about correlation, not causation—and they’re often full of confounding variables. People who eat more “healthy” foods also tend to be higher-income and better educated, and those things affect health outcomes—but nutrition research often fails to control for even those most basic confounders. That’s to say nothing of other factors that may help explain the association between diet and disease, like weight cycling, weight stigma, and other forms of discrimination.
Disordered eating is another factor that I’ve never seen controlled for in a study about nutrition and health (barring studies that are explicitly about eating disorders). And yet disordered eating can have a profound impact on both health outcomes and what/how much people eat.
Even RCTs of diets have their problems, though. It’s hard to have an effective placebo because people usually know what diet they’re getting, unless you’re studying a specific component of the diet that you can give to people in a pill or hide somehow. Otherwise, people generally know if they’re eating, say, a low-carb diet or a gluten-free diet. In fact, most diet studies I’ve read actually have an explicit education component, where they teach people how to follow a particular diet and how to select foods based on the dietary requirements.
Because of all these problems with nutrition research, the idea to simply “trust science” in a blanket way doesn’t really apply when it comes to nutrition, and in my view it can lead us pretty far astray. That’s true in other areas, too: There’s evidence that people who have a broad trust in science are more likely to get duped by pseudoscience and scientific-sounding misinformation than those who think more critically about science. It’s not enough just to say “science says this is the best way to eat;” it’s important to critically examine that research. And when you do, you realize just how much of a hot mess most nutrition research really is. (Exhibit A in the Q&A to follow, and many more examples in my books Anti-Diet and The Wellness Trap.)
So diets generally aren’t based on solid evidence. What about intuitive eating and other non-diet/anti-diet approaches?
Truth be told, there isn’t a huge number of RCTs of intuitive eating and related frameworks. But there are a few that show IE results in better health outcomes than conventional diets on some measures (and similar outcomes on others), and far better adherence over time than dieting. A strong body of observational evidence also links intuitive eating to beneficial outcomes like positive body image, self-esteem, and well-being, and lower levels of disordered eating and anxiety/depression symptoms.
But of course, with the observational data we can’t know for sure if those associations are cause or effect. It’s possible that people who already feel better about themselves and their bodies just naturally eat more intuitively, and that their good health has more to do with their overall well-being than their eating style. I’d say it’s probably a bit of both: intuitive eating is a helpful approach in some ways, and in others it’s simply a marker of greater well-being.
Ultimately, I think of intuitive eating as a conservative approach to eating. Not politically conservative, but medically conservative: It’s an approach of doing less, intervening less, given the shaky state of the science behind most interventions. Intuitive eating is less invasive than diets—it doesn’t dictate what to eat or not eat, when to eat, how much to eat. It doesn’t force people to override their hunger and their desires (and end up rebound-bingeing as a result). It doesn’t endorse restricting calories, carbs, fat, or anything else. It doesn’t prescribe how many hours you should go between meals, or how many plants to eat in a week.
In situations where there’s no solid evidence for most interventions, as with diets—and especially when many of the available interventions carry significant risks, like the risk of disordered eating posed by diets—I think a conservative approach is often the best because it tends to carry the least likelihood of harm.
So to me, given the state of the evidence, intuitive eating feels like a safer bet than dieting.
I have many more thoughts, but I’ll leave it there for now. I’d love to hear from you, though: how do you understand the relationship between intuition and science? Do you see intuitive eating as a (medically) conservative approach, or does it feel like just another diet? Paid subscribers can share your thoughts in the comments, and free subscribers can hit reply.
The Truth About Cycle Syncing
Now it’s Q&A time! This week’s answer is behind the paywall, but everyone can ask their own question here for a chance to have it answered in an upcoming (free) edition.
My question is about syncing your eating with your menstrual cycles. Is changing how you eat at different times in your cycle part of intuitive eating? I’ve seen some people on social media claiming that it is, but I see a lot of red flags in those posts too. Is that real IE, or just diet/wellness culture co-opting the language? I don’t want to explore this if it really is diet-y in nature, but I am also interested in the intersection between IE and menstruation.