834. Is stress really to blame for stubborn belly fat—or is this just the latest internet hype? Let’s look at the science behind cortisol, belly fat, and what truly works.
834. Is stress really to blame for stubborn belly fat—or is this just the latest internet hype? Let’s look at the science behind cortisol, belly fat, and what truly works.
References
Related episodes you may like:
Midlife Weight Gain: Don't Blame Your Metabolism
Find a full transcript here.
Stress is an unavoidable part of life. But can stress hormones really change where your body stores fat? Today, we’re taking a closer look at the so-called ‘cortisol belly.’
Welcome to the Nutrition Diva podcast, a show where we take a closer look at nutrition news, research, fads and trends so that you can make more informed decisions about what you eat. I’m your host, Monica Reinagel, and today I’m tackling a question that June sent in:
“Have you addressed the ‘cortisol belly’ craze?” she writes. “I keep seeing articles about this but I ignore them, figuring it’s just the latest fad. Am I right?”
This is a great question because, like so many other internet rumors, this one has a kernel of truth at its core. Cortisol is a real hormone and there is a relationship between stress, cortisol, and fat storage. But the story that’s being told in the media about ‘cortisol belly’ is at best, an over-simplification. (And, at worst, a bunch of hooey.)
Cortisol is a hormone produced by your adrenal glands, and it plays several important roles. It helps regulate your metabolism, blood sugar, immune function, and it’s a key player in your body’s response to stress. In fact, we couldn’t live without it.
When we experience stressful stimuli–anything from a car suddenly pulling into our lane to a plunge into a cold lake to a terse email from the boss–our adrenal glands respond by releasing adrenalin and cortisol. Adrenalin drives the immediate “fight or flight” reaction—increasing heart rate, sharpening focus, and getting us ready to act. Cortisol’s role is to reallocate metabolic resources in order to keep a steady supply of energy available to our brain and muscles if the stress continues. All of that is normal and adaptive.
The concern is when stress becomes chronic and cortisol levels stay elevated over long periods of time. This can result in sustained high blood sugar levels, which in turn triggers the release of more insulin. Chronically high insulin levels can result in more fat storage–particularly around the abdomen. That, in a nutshell, is how they get to “cortisol belly.”
A lot of the research that first linked cortisol to abdominal fat was done in people with Cushing’s syndrome, a rare condition where the body produces abnormally high levels of cortisol. These patients do tend to accumulate fat around the midsection, and lowering cortisol levels through medical treatment can reduce that fat.
But what happens in Cushing’s patients doesn’t necessarily translate to people without that condition. For most of us, cortisol fluctuates during the day in a fairly normal rhythm. Even if stress causes temporary elevations, that’s not the same thing as pathological cortisol levels. So while it’s possible that chronic stress might nudge fat storage toward the abdomen, it’s certainly not the whole story.
Many other factors can contribute to increased belly fat, including diet, physical activity, sleep, genetics, and other hormones. So while stress and cortisol may play a role, it’s only one piece of a much larger puzzle. On social media, however, you’ll see posts and videos about supplements, “cortisol cocktails,” or “cortisol reset” diets, which allegedly melt away your belly fat by reducing your cortisol levels.
Many of the products and protocols promoted online don’t really have any solid evidence to support them. But once again, some of the hype is based on a kernel of truth. Certain supplements, including ashwagandha and phosphatidylserine, have been shown to reduce the amount of cortisol that is produced in response to lab-induced stress conditions. This effect is often greater in people who report a high level of chronic stress. Of these, ashwagandha is perhaps the best studied. (Interesting side note: ashwagandha belongs to the Solanaceae–or nightshade–family of plants that I talked about just a couple of weeks ago).
The real question, however, is whether these supplements have any long-term effects on adrenal function–or, more to the point–on abdominal fat. And here, you won’t find much evidence beyond testimonials and other anecdotal reports.
The marketing of direct-to-consumer cortisol tests (involving saliva, urine, or hair) add another layer of confusion here. These tests may detect cortisol levels, but the collection methods and reference ranges have not been standardized or validated and they are not recognized by medical authorities as a legitimate diagnostic tool. My fear is that a lot of people may be spending money tests that are more about marketing than medicine, and then end up worrying about a “problem” that isn’t real.
//
So far I’ve thrown a lot of cold water on popular notions about stress, cortisol, and belly fat. But I’m certainly not denying that stress is a thing. For that matter, I know that belly fat is a real concern as well. And not just from a vanity perspective.
Excess body fat that accumulates around the midsection is objectively more dangerous to your health than fat that accumulates in other parts of the body, such as the thighs or arms. It’s linked to an increased risk of metabolic syndrome, cardiovascular disease, and Type 2 diabetes.
And this is why many doctors are moving away from BMI (body mass index) as a health indicator. A high waist circumference or waist-to-hip ratio may be a more accurate indicator of metabolic health.
With all of that said, if you’re concerned about belly fat and you suspect that chronic stress (and cortisol) may be a contributing factor, I do have some concrete steps that you can take. No special belly-fat busting supplements or diet protocols, I’m afraid. It all boils down to a few lifestyle recommendations that you have heard before. But before you roll your eyes, that’s actually good news. Because it means that the following tips won’t just combat belly fat. They’ll also reduce your risk of heart disease, cancer, dementia, arthritis, anxiety and depression!
None of these approaches will magically target belly fat—but together, they can help modulate cortisol, improve resilience to stress, improve your quality of life, and support a healthy body composition over the long term.
So, to come back to June’s original question: Is there any scientific basis for all this buzz about “cortisol belly”? There is a kernel of truth here—chronic stress and elevated cortisol can play a role in fat storage, particularly in the abdominal area. But the way it’s being portrayed in headlines and on social media is oversimplified, exaggerated, and often used to sell you something you don’t need.
The real solutions aren’t found in cortisol cocktails or detox diets. They’re found in the same fundamentals we always come back to: managing stress, staying active, getting enough sleep, and eating a balanced diet.
Thanks for your question, June—and if you’ve got one you’d like me to tackle, you can email me at nutrition@quickanddirtytips.com And be sure to check the show notes for links to related episodes on belly fat and midlife metabolism.
Nutrition Diva is a Quick and Dirty Tips podcast. Holly Hutchings is our Director of Podcasts. Steve Riekeberg is our audio engineer, Morgan Christianson heads up Podcast Operations & Advertising, Rebekah Sebastian is our Manager of Marketing and Publicity and Nat Hoopes is our Marketing and Operations Assistant.
That’s it for this week. Thanks for listening and remember to eat something good for me!