Do You Really Need a Diet for Long Covid?
Q&A: Functional-medicine elimination diets for long Covid, plus what to do if a doctor recommends supplements and probiotics
It’s Q&A day! You can ask your own question here for a chance to have it answered in an upcoming edition.
Just a reminder that these answers are for educational and informational purposes only, and aren’t a substitute for medical or mental-health advice. Although I am a registered dietitian, I’m not your dietitian (unless you happen to be one of my 1:1 clients—hi!—but even then, this email isn’t a session).
The first question today is available to all subscribers (about long Covid and diet), and there’s a bonus one for paid subscribers (about taking supplements).
Hi Christy,
Thank you for all your excellent work. I wanted to sense-check this with you because googling it brings up so many contradictory things I feel like I’m losing my mind.
I have Long Covid. In desperation, I keep falling for alternative medicine’s promises to heal me, cure me, make everything better if I just stop eating gluten, etc. I tried [a controversial program for chronic fatigue], which is at best a lucrative scam and at worst a peppy-sounding cult. The latest I tried is “functional and lifestyle medicine,” and even though I asked not to do an elimination diet because of my history with anorexia, I was told that gluten causes inflammation, that soy and peanuts are harming me (even though I don’t have allergies to any of the above), and basically given a list of things to eliminate. Is functional medicine just a better-branded version of naturopathy? And is there any evidence that changes in diet could help with Long Covid?
Help, I feel like screaming into the night. Thank you so much x
—Kate
I’m so sorry you’re going through this, Kate, and I completely understand falling for alternative-medicine promises in your situation. For new and poorly understood illnesses like long Covid, conventional medicine often doesn’t have great answers because the scientific evidence is still emerging and the clinical picture is muddy. And in times like these, when there’s a gap in what evidence-based medicine can provide, alternative medicine often fills the void with supposed cures that can actually make things worse.
Speaking of which, long Covid is sadly one of those conditions that opportunists tend to exploit. It’s estimated to affect at least 65 million people worldwide, and there are probably many more cases that haven’t been officially diagnosed. With so many people struggling and desperately seeking relief, there’s already a wave of questionable remedies flooding the market, and surely many more to come.
Now, to answer your questions: First of all, I think you’re onto something when you say that functional medicine is a better-branded version of naturopathy. There are some differences, but at its core, functional medicine actually has roots in naturopathy (also known as “natural medicine”), and it borrows a lot of concepts from that older approach.
Both these methods share the belief that the body can heal itself from various ailments if you just consume the right combo of foods and supplements, which for the most part isn’t backed by solid evidence. Functional medicine even goes so far as to call it a “food first” approach. The two modalities also both tend to vilify gluten, dairy, and other foods labeled as “inflammatory,” without good evidence that these foods are harmful for more than a small percentage of people with genuine sensitivities.
Both modalities claim to get to the “root cause” of illness and “treat the whole person,” as opposed to viewing the body as a collection of different systems, the way conventional medicine is (often rightly) accused of doing. And for people who feel let down by the regular healthcare system, this approach can be incredibly appealing—it was to me, too, years ago.
The irony, though, is that the so-called root cause is often predetermined (gluten, dairy, other “inflammatory” foods), and the treatment typically focuses just on the physical (cutting out foods, taking supplements), which can have a profoundly negative impact on mental and emotional well-being. Although many naturopaths, functional-medicine practitioners, and other alternative providers criticize conventional medicine as being “one size fits all,” their methods are often the same.
One difference between functional medicine and naturopathy used to be that FM was more into high-tech stuff, especially lab tests, but today there are plenty of naturopaths ordering labs, too. In both fields, the tests are often scientifically unvalidated. (Quackwatch has a good list here of some common dubious tests, and I’ve written here about the GI-MAP test and other food-sensitivity tests.)
Another difference between functional medicine and naturopathy is that FM has some high-profile MD proponents, which might make it seem more like a mainstream medical specialty than an alternative practice. But honestly, I’d lean more toward calling it alternative medicine.
When it comes to eating disorders, functional medicine has many of the same problems as other alt-med approaches. In many cases, providers of functional medicine just don’t understand disordered eating—and their “food-first” philosophy can actually make things worse.
Of course there are exceptions. Some functional-medicine practitioners are wonderfully caring and probably wouldn’t give dietary restrictions to someone with a history of an eating disorder. FM providers who do encourage eliminating foods likely aren’t aware of just how harmful those recommendations can be. And this isn’t solely a functional-medicine problem—even regular MDs often struggle to understand eating disorders and might inadvertently fan the flames. Plus, in some cases FM providers (like others in alternative medicine) have more time and show more empathy for their patients who are struggling with poorly understood conditions like long Covid.
Still, given that functional medicine tends to view diets as first-line treatments, there’s probably a higher chance that FM could damage your relationship with food than there is with conventional medicine. In general, I think functional medicine isn’t the best place to turn if you’ve ever struggled with disordered eating. (The same is true of lifestyle medicine, which I answered a question about earlier this year.)
Now to your second question: The short answer is that there isn’t any good evidence to support the use of diets for long Covid. Specifically, my research did not find any randomized, controlled trials of dietary changes for post-Covid conditions. There are several papers (which I won’t link to here) advocating particular diets anyway, but they are purely theoretical and don’t actually study the effects of diets on real humans with long Covid.
The one thing I think is important to note is that people who’ve had Covid are at risk of malnutrition and muscle loss from the disease, so eating enough is likely important for recovery. But beyond that, any dietary recommendations are speculative at best.
In short: there’s no reason to eliminate gluten, soy, peanuts, or any other food for managing long Covid (unless you have a legitimate allergy to any of these foods, diagnosed with validated tests—but that’s not specific to long Covid, that’s just good self-care). Going forward, I’d recommend seeking out a conventional doctor who’s knowledgeable about post-Covid conditions AND willing to respect your desire not to diet due to your eating-disorder history, though I know that is probably a tall order. (To any MDs reading this who fit the bill, please reach out!)
Unfortunately we’re still in the early stages of understanding long Covid, and I know that’s incredibly frustrating to anyone struggling with the condition. I can understand why you feel like screaming into the night, Kate! For now, in the absence of good treatments, it might help simply to remember that your eating-disorder recovery is particularly vulnerable during this time, and to be extra vigilant in protecting it.
Thanks so much for the great question, and thanks to all the free subscribers for reading! Paid subscribers can stick around for the bonus Q&A, and everyone can ask their own questions for a chance to have them answered in an upcoming newsletter.
I have a question about how to approach taking supplements when a doctor has asked me to do so. My doctor (a regular MD, not a naturopath or functional-medicine doctor) has asked me to take vitamins D and B12 to treat low levels of these vitamins in my blood, as well as probiotics to help with GI issues. I find this gray area confusing, because I'm not being prescribed a medication by this doctor, rather they are asking me to go to my local grocery store or go online to purchase unregulated supplements to treat my conditions. What insight can you give concerning this desire to follow a doctor's advice while still being wary of buying supplements? Does it make sense to you that this can be confusing for patients, or am I missing something? Thanks for any thoughts you can share.
—Lauren