You’re not alone if you’ve recently found yourself searching for answers to questions like “Can you suddenly have hypothyroidism?” The answer is yes—but here’s the twist. That sudden shift in how your body processes iodine could be the result of a condition your doctor hasn’t considered yet: a cerebrospinal fluid (CSF) leak. 

The odds of a CSF leak causing your thyroid problems become even higher if you’ve recently had a lumbar puncture, epidural steroid injection, or labor epidural. Even sneezing too hard can cause a spontaneous spinal leak if it causes an injury, such as a herniated disc. 

Hi, I’m Marion Davis, a CSF patient advocate and founder of Medical Office Marketing. I’ll explore this topic in great detail during my upcoming talk for registered dietitians on “Iodine, Thyroid Health, and the Hidden Role of Spinal Leaks.” Save a spot now to learn why levothyroxine prescriptions aren’t always the answer to a patient’s thyroid problem. We will also be offering a patient-focused webinar in May 2025. Sign up for our newsletter and choose your role, whether you are a patient or a dietitian, to receive tailored updates.

Can You Suddenly Have Hypothyroidism? Let’s Talk About Triggers

Thyroid disorders don’t always develop slowly. Sudden hypothyroidism or hyperthyroidism is an often missed co-occurring condition with spinal CSF leaks that makes you gain or lose weight inexplicably, leaves you feeling constantly fatigued, and makes your heart race like you’ve been chugging espresso all day. 

Spinal CSF leaks lead to intracranial hypovolemia and brain sag as the volume of this protective fluid decreases, throwing the pituitary gland out of balance. The result is hormonal chaos, including thyroid disorders. When we think of hormones, we commonly think of sex hormones. 

One radiologist who asserts spinal CSF leak expertise told me once that he overlooks the significant sign of an engorged pituitary in women because women have hormonal fluctuations. This is a troubling assertion. As established by the Bern score, fluctuations have normal ranges. But the pituitary is an integral part of the hypothalamus-pituitary-thyroid (HPT) axis. 

So many mothers report in Facebook groups that they are told their persistent headache after labor is simply hormonal. And perhaps it is partially as they have hugely enlarged pituitaries secondary to intracranial hypovolemia from a spinal leak, as I have seen in women’s MRIs who never had a physician point this out to them. 

Perhaps they have high levels of free T4 as a thyroid hormone that is creating feelings of panic and doom, increasing their heart rates to a resting heart rate of 140 BPM, making their lives a living hell, and putting them at risk of cardiovascular damage and/or death from a thyroid storm. Hormones can do that.      

Physicians often skip the endocrinological connection between iodine intake and supplementation and thyroid function, especially in patients with underlying sensitivities (as can happen when your pituitary is enlarged), defaulting to medication like levothyroxine without digging deeper into potential causes of a patient’s thyroid dysfunction. 

Here’s a real-life example: One spinal leak patient with hypothyroidism developed severe hyperthyroidism within 24 hours of taking 25 mcg of levothyroxine to the extent that hospitalization was needed. This isn’t some rare occurrence, and it’s time for the medical community to wake up to the fact that thyroid mismanagement is putting people at risk, particularly those with spinal leaks. 

Why “Sudden” Thyroid Issues Demand a Dietitian’s Expertise

If you suddenly develop a thyroid disorder, the first step is to figure out what has changed. Your diet, especially your iodine intake, tremendously impacts the function of the thyroid gland.

Here’s how that works.

• The Wolff-Chaikoff effect: This occurs when your thyroid stops hormone production if it senses too much iodine, triggering hypothyroidism. Consuming supplements, seaweed, and fortified foods can lead to excessive iodine intake. 
• The Jod-Basedow effect: Iodine overload can overstimulate the thyroids of vulnerable populations, such as people with thyroid nodules, leading to hyperthyroidism. 

A 1998 case study made this reality evident. Iodine-deficient patients were given 250 mcg of iodine daily, 100 mcg more than the recommended daily allowance. Seven developed subclinical (mild) hypothyroidism, one participant had severe hypothyroidism, and another developed hyperthyroidism. All recovered once their iodine intake was stopped. 

What made the study even more interesting was that it occurred in a iodine-deficient area (typically a landlocked region with little access to naturally iodine-rich foods), proving that even small increases in iodine intake can cause thyroid disorders. The moral of this case study is that a thyroid-knowledgeable dietitian should be on your list of healthcare providers you consult with, instead of only seeing an endocrinologist if you suddenly develop hypo or hyperthyroidism. 

If any practitioner presents you with the oversimplified statement that hypothyroidism is a result of iodine deficiency and hyperthyroidism is from too much iodine, run. Far too many functional medicine doctors and even dietitians have told us that they encourage iodine supplements in the cases of patients with hypothyroidism. 

The body tries to throw itself into hypothyroidism as a protective mechanism first, with the TSH increasing essentially as the brakes to stop a runaway train with too much fuel (the free T4 as an indicator of fuel). Neither hypothyroidism or hyperthyroidism is an ideal situation for the body, but the body will opt for hypothyroidism and slamming the brakes on hormone production rather than allowing the body to go into hyperthyroidism as much as it possibly can. 

Endocrinologists often do not consider nor understand the systems at play here. Free T4 can be normal or start to drop due to suppression from elevated TSH because the body is trying to stop the overproduction of free T4 due to mechanisms such as over-intake of iodine, causing overproduction of T4. These endocrinologists often believe that elevated TSH is the body's response to insufficient free T4 being created and thus introduce levothyroxine for synthetic thyroxine (T4).    

The Elephant in the Exam Room

Here’s a hard truth you might have already found out firsthand, like I have. If you’ve gained weight due to thyroid issues or a spinal leak, you might have to deal with weight bias. Physicians often blame the symptoms of both conditions on obesity, overlooking conditions like intracranial hypotension. 

[Related: How weight bias impacts patients seeking spinal leak treatment]

Patients with spinal leaks are frequently misdiagnosed with lifestyle or stress-related issues, blamed for their symptoms while they continue losing cerebrospinal fluid, or prescribed thyroid meds without any root cause analysis, a recipe for disaster. 

What You Can Do Next If You Suddenly Have Hypothyroidism 

The best treatment for hypothyroidism or hyperthyroidism is pinpointing the root cause so it can be treated. Some things you should keep in mind include:

• Question the “sudden”: Go over your recent activities to help determine the cause of your thyroid disorder. Have you recently had a back injury or a medical procedure that involved puncturing the dura, like an epidural steroid injection or lumbar puncture? 
• Track your iodine: Work with a dietitian to audit your diet. That healthy seaweed salad you thought would help you lose weight could be the culprit. 
• Push for imaging: Request a brain MRI or spinal imaging to rule out a CSF leak from potential causes. Be careful about using contrast dye with iodine in it. A non-contrast dye brain MRI can still show plenty of information. The main reason contrast dye is used in spinal CSF leak cases is to look for the presence of a sign that is often incorrectly used as a present/absent diagnosis marker when research shows this sign tends to disappear over time after onset of the spinal leak and is not a reliable marker. Instead, the Bern score should be used to look at many aspects of the brain and how structures are positioned. Find a different physician if a lumbar puncture is recommended for diagnostics instead with a focus only on intracranial pressure. Intracranial pressure is an unreliable measurement for a spinal leak as spinal leaks cause low volume. How the body responds to low volume is what leads to low, normal, or high brain pressure. A lumbar puncture is way too invasive and could cause a new spinal leak. Research also shows that the Bern Score, which involves brain imaging, is more accurate for diagnosing spinal CSF leaks than intracranial pressure readings. 

Sudden Thyroid Issues Aren’t Random—Here’s How to Fight Back

In my upcoming webinar for dietitians, I’ll share:

• My personal experience with spinal leaks.
• How the condition predisposed me to iodine-related thyroid issues.
• Population studies on the correlation between iodine supplementation or iodine-fortified foods and increases in thyroid disorders.
• How BMI discrimination impacts access to quality spinal CSF leak care.

I’ll also discuss how dietitians can offer a results-focused approach to providing patients with the knowledge and guidance they need to recover. For example, they can review the daily iodine intake of patients with thyroid disorders and support them as these patients self-advocate for various tests with their primary care physicians and endocrinologists. 

In an area where patients are hungry for more information on how to address their hypothyroidism naturally versus the heavily overprescribed, one-size-fits-all approach of levothyroxine, dietitians can step into this high-impact niche and spearhead thyroid care where other clinicians have failed to meet this need. 

In Canada, one in ten people has a thyroid disorder. In the US, the American Thyroid Association (ATA) notes that more than 12 percent of the US population has a thyroid disorder, with an additional comforting note that the “causes of thyroid problems are largely unknown.” There lies the problem with the standard approach common in medicine of setting the precedent that most causes are unknown; therefore, it is acceptable for physicians not to search for a cause in practice and simply throw levothyroxine at everyone in treatment. 

This is where you can step in as a registered dietitian and audit a patient’s diet, make recommendations such as maintaining the RDA of iodine rather than consuming large amounts, and collaborate with physicians who are part of your patients’ care teams to set up tests to assess progress. 

As I have seen in my own body, a reduction of 240 mcg/day of iodine to 120 mcg/day of iodine from eggs alone dropped me from a TSH high of over 14 to a TSH of about 6.5 in a matter of weeks after more than a year of consuming this level of iodine and being in hypothyroidism. This is a transition from overt hypothyroidism to subclinical hypothyroidism with a noticeable change in metabolism.         

Reserve your seat here. This is the first step in creating value in a high-demand but underserved area.