Is your low blood sugar a symptom of insulin resistance or mild dysfunction of the autonomic nervous system?
In episode 16 of my podcast, I return to the topic of hypoglycemia to discuss the difference between insulin resistance and dysautonomia, why unstable blood sugar does not automatically mean insulin resistance, and my concerns about continuous glucose monitoring.
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Transcript
If you’ve detected unstable blood sugar with a continuous glucose monitor, what is the significance of that? Does it mean insulin resistance? Does it perhaps even cause insulin resistance? The short answer, if you’re a young woman, is “Probably not,” and in this episode, I’ll explain why.
Welcome back to the podcast. I’m your host, Lara Briden, a naturopathic doctor and author of the books Period Repair Manual, Hormone Repair Manual, and a new book about metabolic health called Metabolism Repair for Women in most parts of the world and The Metabolism Reset in Australia and New Zealand.
This episode was supposed to be about endometriosis, and I promise I will return to endometriosis next episode because there have been some interesting developments.
First, though, I need to do a second episode about low blood sugar. My first one was called “Hypoglycemia in young women: The science behind ‘hangry.” So, if you haven’t already listened to that, maybe go back and check it out.
This sequel episode is to clarify a few things and address the confusion between insulin resistance, which affects a lot of people generally, and mild dysautonomia, which affects a lot of young women specifically.
First, insulin resistance is a hormonal condition associated with chronically elevated levels of the hormone insulin. Unstable blood sugar, including low blood sugar sometimes, can be a symptom of insulin resistance, but the central feature of the condition is chronically high insulin. And it’s actually the high insulin that causes many of the negative metabolic outcomes, such as a reduced ability to burn fat for energy and certain types of inflammation. I’ll just point out that the metabolic type of inflammation from insulin resistance is typically not a driver of pelvic pain or endometriosis. Pelvic pain needs a different approach, which will be the topic of my next podcast.
In contrast to insulin resistance—and as I discussed in my “hangry” episode—dysautonomia is mild dysfunction of the autonomic nervous system. In other words, it’s impaired oscillation between the parasympathetic and sympathetic nervous systems. If you have ever tracked HRV or heart rate variability, you’re tracking the health or functioning of your autonomic nervous system.
Symptoms of dysautonomia include low blood pressure, fainting, fatigue, cold hands and feet, IBS or irritable bowel syndrome, mast cell activation, migraines, sleep problems, and a tendency to hypoglycemia or low blood sugar. That’s because of the blunted glucagon response that I described in the previous episode. So, it’s a situation of having less glucagon to push up on blood sugar, paired with a steeper sympathetic activation or a bigger rush of adrenaline in response to that hypoglycemia.
Now, although anyone of any age can experience it, dysautonomia is way more common in young people because—surprisingly—autonomic function doesn’t fully mature or stabilize until about age 25. Young women are particularly vulnerable, thanks to estrogen’s vasodilating effects and various hormonal aspects of the menstrual cycle. As a result, many teen girls and women in their twenties are prone to mild dysautonomia—to the point that it could almost be viewed as a developmental stage or part of female puberty. So, most women will outgrow it. But not all women, of course! Dysautonomia can persist later in life, especially for people with hypermobility, which is closely associated with autonomic nervous system dysfunction.
Alternatively, dysautonomia can emerge later in life as a result of things like viral infection or reactivation, surgery, inflammation, injury, trauma, or the hormonal transition state of perimenopause. In fact, dysautonomia and mast cell activation are common mechanisms of some perimenopause symptoms.
Dysautonomia is a big topic, and so is treatment for it. Broadly, for dysautonomia that has emerged later in life, it can be necessary to treat or address the initiating factor or driver, such as a viral infection or post-viral syndrome, in which case something like low-dose naltrexone can be helpful—just as an example.
Plus, you want to think about general support for the autonomic nervous system, including electrolytes (I discussed that in the previous episode) and nutrients for the parasympathetic nervous system, such as magnesium, choline, and pantothenic acid. And signals of safety, which are all the cues or signals that tell your autonomic nervous system that you’re safe and okay. They include things like connecting with people, spending time outdoors, getting a massage, and eating nourishing food. As mentioned, the autonomic nervous system is strongly affected by female hormones, so it may also be necessary to address a menstrual cycle issue or get off hormonal birth control.
Supporting the autonomic nervous system is also important for treating and reversing insulin resistance. I explore that in my metabolism book, where I expand “signals of safety” to “signals of safety and satiety.” So, in that sense, there is significant overlap between dysautonomia and insulin resistance—just as there’s overlap between almost every aspect of health!
That said, dysautonomia and insulin resistance are different conditions that require different assessments and, to some extent, different treatments. For example, a young woman experiencing low blood sugar because of mild (somewhat routine) dysautonomia is not likely to require the insulin-sensitizing medication metformin. In fact, she could feel a lot worse from metformin.
At the same time, a woman with moderate to severe PCOS and confirmed insulin resistance could benefit from metformin—or from one of the many natural insulin-sensitizing treatments. That woman could also be young, so it’s not so much about age as it is about understanding whether or not there’s insulin resistance.
That means actually assessing for insulin resistance with biomarkers, such as high triglycerides, fatty liver, and maybe testing the hormone insulin. For more on assessment, see Chapter 5 of my metabolism book. And remember that a normal blood glucose or HbA1C cannot rule out insulin resistance because the main feature of insulin resistance is chronically elevated insulin. In fact, Insulin can be high for decades before glucose finally goes out of range. If you’re watching the video, this chart of insulin and glucose over decades is from insulin resistance researcher Benjamin Bikman.
A few more points:
- A high body mass index or BMI is NOT solid evidence of insulin resistance.
- Nor is an ultrasound finding of polycystic ovaries.
- Nor is the symptom of hypoglycemia, our topic of today.
That said, the specific pattern of hypoglycemia at 3 am does seem to be quite common in my patients with insulin resistance, so that could be a bit more of a precise indicator.
Returning to the questions I posed at the beginning of the episode: “Does unstable blood sugar automatically mean insulin resistance?” The answer is No. Hypoglycemia can be a symptom of insulin resistance, but as we’ve seen, it can also be a symptom of dysautonomia, especially in young women.
Next question: “Does unstable blood sugar increase the future risk of insulin resistance?” The answer is Not directly, in that many young women with hypoglycemia from dysautonomia will not go on to develop insulin resistance. However, unstable blood sugar could indirectly increase the risk for those women who experience hypoglycemia-induced binging and eventual food addiction. For more about food addiction, see my book and episode 14.
Finally, a related question: “Do spikes of blood sugar cause insulin resistance by producing a higher, more frequent release of insulin?” The answer is Yes and no. Long term, a tendency to high sugar spikes could contribute to insulin resistance, but through my lens, it’s not the main driver.
Take frequent consumption of ultra-refined carbohydrates as an example. They undoubtedly do contribute to insulin resistance, and one mechanism could be that they repeatedly hyperstimulate insulin. Okay, but another mechanism is that ultra-refined carbohydrates can cause small intestinal bacterial overgrowth, intestinal permeability, and metabolic endotoxemia—and then those bacterial toxins can directly induce insulin resistance. So, it’s not just that glucose has an insulin-stimulating effect.
Big picture, other underlying drivers of insulin resistance include medications (such as some types of hormonal birth control), circadian misalignment, microbiome problems, emulsifiers, high-dose fructose, high-dose omega-6, and nutrient deficiencies, just to name a few. And once insulin resistance has been established by one or more of those causes, unstable blood sugar, including episodes of low blood sugar, can be the result or symptom.
So, to treat hypoglycemia, you need to treat the cause. For dysautonomia, review the treatments I provided in the previous episode, including protein and support for the autonomic nervous system. For insulin resistance, consider the strategies I provide in my book, including fixing the gut and taking inositol, just as a couple of examples.
A few parting thoughts about continuous glucose monitors or CGMs:
They were invented for people with diabetes, especially type 1 diabetes, and are incredibly helpful for that purpose. That’s a different conversation. In my view, CGMs are less helpful for people without diabetes, although they can detect hypoglycemia and, therefore, provide insight into anxiety symptoms that are actually hypoglycemia. That’s useful.
CGMs can also help people gauge what kind of glucose reaction they get from different foods—but with the understanding that there can be significant variation day to day. As in… the same foods can cause a strong glucose spike one day but not another. Or, for women—I might point out—the same foods can cause a strong glucose spike in one part of the menstrual cycle but not another. Female hormones have a huge effect. For that reason, I’m honestly not convinced as to the value of glucose monitors, and my observation with patients is that hyper-focussing on blood glucose or trying to micromanage it can cause anxiety.
I hope that’s been helpful, and I’ll finish with this: With almost any symptom, particularly a hormonal symptom like low blood sugar, a great place to start is to support or regulate the autonomic nervous system. For a fascinating deep dive into dysautonomia, hypermobility, and mast cell activation, check out a presentation by Dr Andrew Maxwell that I’ll link to in the show notes. It’s quite technical but also very illuminating.
And thank you so much for listening! Or watching. Please share and leave a review. You can also leave a comment on the YouTube video, on the blog post associated with this episode at LaraBriden.com, or in my forum—on the topic I’ll create for the episode.
And I’ll see you next time for the promised discussion of endometriosis and persistent pelvic pain.