Insulin resistance isn't just a weight thing (PCOS + perimenopause edition)
Dr. Jennah Miller, Naturopathic Doctor
Can we talk about insulin resistance for a second, without immediately also talking about weight and body size?
Every conversation about insulin resistance seems to start and end with "lose weight and it'll fix itself." I hear it from patients constantly. The frustrating thing is, the research doesn't back that up as a blanket rule. Insulin resistance shows up in people at every size. It shows up in PCOS regardless of body size and composition, and it shows up in perimenopause whether or not your weight has changed at all through that transition. Treating body size as the main marker for health and the whole picture, means a lot of people are made to feel like their metabolic health is somehow their fault.
Here’s what evidence-based, weight-inclusive care for insulin resistance can look like.
PCOS + insulin resistance: it's not only a "larger body" issue
There's this persistent idea that insulin resistance in PCOS is basically a side effect of excess weight. But "lean PCOS" - technically defines as PCOS in a body with a BMI under 25, but let’s call it PCOS in folks who exist in smaller bodies - is a real, well-documented clinical picture, and it is not metabolically off the hook. One study found insulin resistance in 47% of “ lean” folks with PCOS. A 2025 study on teens went further: adolescents with lean PCOS actually showed higher insulin resistance than their peers who existed in larger bodies, with metabolic syndrome risk elevated regardless of body size. Across the board, researchers are landing on the same conclusion - the metabolic risk of PCOS spans the entire body size spectrum, not just the higher end of it.
That tells us something important: insulin resistance in PCOS is being driven by the underlying picture (androgen excess, how the ovaries respond to insulin, adipokine dysfunction) not simply by how much adipose tissue someone is carrying. It’s not the main mechanism, and it's definitely not the only door in for treatment. There's even older research on normal-weight PCOS patients showing that directly lowering insulin secretion improved androgen levels and cycle regularity, with zero change in weight required to get there. That's a pretty strong hint that insulin signaling, not body size, is the lever actually worth pulling.
Then perimenopause piles on its own version of this
If you're dealing with PCOS and perimenopause at the same time, you've basically got two separate processes pushing on insulin resistance, stacking on top of each other.
The SWAN study (one of the largest long-term studies we have on the menopause transition) found that insulin resistance and high HbA1c in early perimenopause predicted worse hot flashes and night sweats down the line, and researchers now think elevated insulin might be an early, upstream driver of a lot of what shows up metabolically during this transition. Other researchers studying the liver's role in this have noted that the odds of developing metabolic syndrome peak during perimenopause independent of age, and that changes in how the liver responds to insulin seem to be a primary driver. Declining, fluctuating estrogen is directly implicated here too. Estrogen has real anti-inflammatory, metabolically protective effects, and losing it changes how your liver and muscles handle glucose - not just what the scale says.
None of this is a willpower problem, it’s a nuanced cascade of hormones and endocrinology.
Why weight-first care actually backfires here
This is where taking a HAES-aligned approach isn't just a nicer philosophy - it's clinically the smarter move. When weight loss becomes the main marker of "success," two things tend to happen: the actual insulin picture gets under-investigated, and people in larger bodies get worse care, full stop.
The data on that second part is not subtle. Weight stigma in healthcare settings shows up as shorter appointments, fewer tests ordered, and lower trust between patient and provider. And weight stigma has consequences of its own. One large study found people who reported experiencing weight discrimination had a 60% higher risk of dying, independent of their BMI. Weight stigma has also been linked to higher cortisol and more stress-driven eating, which means the stigma itself can actually feed the exact metabolic dysfunction it claims to be "fixing."
So chasing weight loss as the primary treatment target can genuinely work against you here - through the stress-hormone pathway, and through the very real care gaps that open up once a patient's size becomes the whole conversation instead of one small piece of it.
What weight-inclusive insulin resistance care actually looks like
Weight-inclusive doesn't mean hands-off. It means treating the metabolic picture directly, without making weight change the price of admission. In practice, that means:
Testing what actually needs testing - fasting insulin, HOMA-IR, lipids, inflammatory markers - no matter what the scale says or whether you "look" like someone with insulin resistance.
Targeting insulin signaling directly, through food, movement, sleep, and nervous system support that improve insulin sensitivity as the goal itself, not as a means to shrink a body.
Screening for lean PCOS and perimenopausal insulin resistance even when someone doesn't fit the stereotypical body size associated with insulin resistance, because as the research above shows, that presentation is fairly common.
Taking weight stigma out of the appointment entirely, because a patient who trusts their provider, is able to feel safe and heard in their appointment, and this allows them to collaborate together in a treatment plan that works with their life and body in a way that is supportive and not punitive
Health-promoting behaviors improve insulin sensitivity, inflammation, and quality of life at every body size. That's not a softer standard of care - it's a more accurate one, pointed at the mechanism that's actually driving your symptoms instead of a number that was never the whole story.
Navigating insulin resistance with PCOS or perimenopause (or both, no judgment, it's a lot) and want support that actually looks at you? Book a free 15-minute consult and let's figure out what's actually going on.
Dr. Jennah Miller, ND is a Toronto + Halifax based Naturopathic Doctor with a passion for menstrual and hormonal health. She works with people with periods to co-create supportive, individualized care for PCOS/PMOS, PMS, perimenopause, and fertility - care that never requires a weight change as a precondition for taking your metabolic health seriously.
References
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