Insulin Resistance and Metabolism Repair for Women (Episode 533)

Full Transcript: Episode 533

This is the Fertility Friday Podcast, episode number 533.

In today’s show, I’m sharing my recent interview with Lara Briden. She joined me to talk about some of the concepts she covered in her new book, Metabolism Repair for Women. Let me tell you a little bit about Lara if you’re not familiar. Lara Briden is a naturopath and the bestselling author of the books Period Repair Manual, Hormone Repair Manual, and her newest book, Metabolism Repair for Women — practical guides to treating period problems with nutrition, supplements, and body-identical hormones. A graduate of the Canadian College of Naturopathic Medicine and the University of Calgary, Lara serves on several scientific advisory committees, including the Centre for Ovulation and Menstruation Research at the University of British Columbia. Lara has consulting rooms in Christchurch, New Zealand, where she treats women with PCOS, PMS, endometriosis, perimenopause, and many other hormone and period-related health problems.

In today’s episode, we are focusing on metabolism. I found it very interesting that Lara described her book not as a weight loss book, but yet it still has the implication to improve and reset your metabolism, which can therefore lead to weight loss. We’re touching on that topic and so much more in today’s episode. So without further ado, let’s go ahead and jump right in.

I’m so excited to be here once again with Lara Briden. As I think about it, you were one of my very first interviews. I feel like you were episode seven.

Lara: I love it. We’ve known each other a long time, and we’re both Canadian. And we did meet in person one time, which is quite a feat in the modern online age. So yeah, I always love talking to you.

Lisa: Well, thank you so much for being here. Congratulations on your newest book, Metabolism Repair for Women. Such a needed resource and really excited to delve into it. Maybe just introduce yourself — some of my listeners might not have heard of you before — and let us know why you decided to write this book now.

Lara: I’m a naturopathic doctor. I’ve been doing that for about 25 years. I’m Canadian, as I mentioned, but I live in New Zealand currently. I have a couple of other books — Period Repair Manual, which is for women of any age, how to have better menstrual cycles; Hormone Repair Manual, which is for women over 40 and is all about perimenopause; and then this one, Metabolism Repair for Women, which is specifically about metabolic health, metabolic dysfunction, insulin resistance, and how to reverse that.

My journey to this book was, as with my other two books, through my work with my patients — just seeing on the ground what they needed. Over the decades, I’ve come to understand how important metabolic health is for women’s health. It’s a bidirectional relationship: having good metabolic health or good insulin sensitivity can make for better periods and better fertility, and conversely, female hormones also impact metabolic health.

Lisa: Let’s start by talking about what insulin resistance is and what healthy metabolism would look like.

Lara: Let’s start with what healthy metabolism looks like because it’s really about energy. It’s about being able to extract the energy you need from food and from your body fat stores. Our healthy baseline is that we’re actually supposed to be burning mostly fat at rest and only tipping into burning a lot of carbs when we’re doing heavier exercise. That’s what’s called metabolic flexibility — being able to always tap into your body fat stores. When you’re metabolically flexible or metabolically healthy, you just naturally feel less hungry. You can reach satiation with your meals, have stable blood sugar, and don’t have blood sugar crashes where you need to keep snacking just to keep your energy up.

But with what’s called metabolic inflexibility — also called insulin resistance — people get locked into a carb-burning state. Understandably, they’ll need granola bars or trail mix just to keep going through the day, and that has many negative downstream health effects. For one thing, it just makes you tired. It can also contribute to weight gain. In some ways this is a weight loss book, but as I talk about in the early pages, if the focus is too much on body size, that muddies the water. The focus should really be on metabolic health and whether someone has insulin resistance or not.

Lisa: How did you see this playing out with your patients — their energy, their menstrual cycles, their weight?

Lara: The big one is of course polycystic ovary syndrome, or PCOS. The insulin resistance associated with that can directly impair ovulation and impair progesterone. PCOS is a condition of excess androgens or testosterone, and testosterone in women promotes insulin resistance. So it’s hard to know which comes first — the high androgens or the insulin resistance. But once that vicious cycle gets going, women usually need help to break out of it.

Insulin resistance also has a pretty big effect on premenstrual mood symptoms. And of course it’s a big player in perimenopausal symptoms — not only the weight gain associated with perimenopause, but some of the symptoms themselves. Some of the neurological symptoms like hot flashes and brain fog are associated with a reduction in brain energy, which is really just about the brain being less able to get the energy it needs from glucose, and being unable to rely on fat for energy because of insulin resistance.

Lisa: Can you define insulin resistance for us and explain the difference between physiological issues that predispose someone to blood sugar problems versus just not eating enough protein?

Lara: There’s a whole group of young women — I would have been one of them, and probably you as well — who are having blood sugar crashes for a combination of hormonal reasons and not enough protein in the morning, who do not have insulin resistance. So insulin resistance is not the only cause of low blood sugar.

Insulin resistance itself is best described as being associated with chronically elevated levels of insulin. Even though insulin resistance is kind of synonymous with pre-diabetes and the two terms get used together, that implies that blood sugar must be elevated — but it’s not. With chronically elevated insulin, which can be in place for decades before type 2 diabetes develops, the hormone insulin is high but blood sugar is all over the place. It can be a little bit high, normal, or low at times. There’s a type of hypoglycemia that is essentially caused by insulin resistance — something called reactive hypoglycemia, which is a drop in blood sugar two to three hours after a meal. That’s pretty common with PCOS.

The signs of insulin resistance — people need to know their doctors often aren’t looking for it. A normal blood glucose reading or even an HbA1c won’t pick up insulin resistance. Instead, you need to look for signs like weight gain around the middle, specifically waist-to-hip ratio, which is quite an accurate surrogate marker of insulin resistance. You also get that specific kind of visceral fat deposition. And bum fat is actually quite healthy from a metabolic perspective — it’s quite unique to women and largely genetic. Visceral fat is deeper — it can feel like a hard kind of pressure or almost a shelf under the ribcage. Other signs include elevated triglycerides, elevated cholesterol, sometimes elevated liver enzymes, and if the doctor has mentioned anything about fatty liver, that’s almost always insulin resistance. In more severe cases, there can be skin tags and darkening of the skin around the neck and under the arms.

Lisa: What causes insulin resistance?

Lara: It’s happening down at the level of the mitochondria and the cell — it’s all about signaling around energy use that has gone a little off the rails. We’re in an epidemic of it now. A conservative estimate suggests it probably affects at least 40% of adults, certainly in Western countries, and it’s likely higher than that.

Scientists all agree the increase is being driven by exposure to the modern food environment, in combination with environmental toxins, possibly disruption of circadian rhythm, and changes to the microbiome. And the scary thing is that the problem is amplifying generation to generation through epigenetics — when genes get switched on or off in one individual or generation and those switches get passed on. This is why we’re now seeing people getting insulin resistance younger and younger. It used to be something that only happened in your 50s. We’re now seeing fatty liver and type 2 diabetes in kids, which previous generations of doctors would not have believed was possible.

Lisa: You touched on the issue with our food quality. Can you expand on that?

Lara: Ultra-processed carbohydrates lose their cell wall during processing. When they go through the gut, they don’t signal the satiety hormones that are supposed to tell the brain we’ve had food. They just go straight down into the gut and trigger bacterial overgrowth — this is where SIBO or small intestinal bacterial overgrowth comes in — and promote intestinal permeability, which is a big driver of insulin resistance.

High-fructose intake hijacks an ancient survival mechanism that pushes us into an insulin-resistant state. Processed seed oils also appear to be doing something problematic to insulin signaling — the science is starting to paint that picture. The shift away from animal fats like butter and lard toward vegetable oils may have been a significant part of the shift toward widespread insulin resistance.

And ultra-processed foods can also contribute to what I’d call food addiction — which is a controversial chapter in the book, but the evidence is growing. The answer to the criticism that “how can you be addicted to food?” is that it’s not really food — people are addicted to food-like substances that confuse the brain’s reward pathways entirely.

Lisa: What are the biggest obstacles for women trying to address this?

Lara: I list 23 metabolic obstacles in the book. The obvious ones are exposure to ultra-processed food, sugar, and alcohol. Beyond those, obstacles include food sensitivities, gut problems like SIBO and intestinal permeability, hormonal birth control, thyroid problems, nutrient deficiencies, chronic stress, and circadian misalignment.

I categorize each obstacle by priority and difficulty, and I recommend people start with the high-priority easy fixes. One of the highest-priority and easiest fixes is circadian rhythm alignment: get morning light outside, shelter from artificial light in the evening, synchronize meals with waking hours. Getting a good hit of protein in the morning also helps entrain circadian rhythm and not eating late into the evening are simple starting points.

Lisa: Let’s talk about weight loss. How does your approach address women who want to lose weight without disrupting their menstrual cycles?

Lara: The healthy menstrual cycle is a sign of health. By definition, any intervention or strategy that has the outcome of disrupting ovulation and the menstrual cycle is not healthy. What I’m talking about — sheltering from vegetable oil, sheltering from fructose, adding in some muscle-building movement, getting outside — especially for a woman whose starting place has been insulin resistance and PCOS, her menstrual cycle is going to improve. We can safely say that if it’s a health-based, metabolic-enhancing process, one outcome has to be a healthier menstrual cycle. If the menstrual cycle is disrupted, the intervention is working against health.

The problem with undereating plus exercise is that the body — from a survival perspective — conserves everywhere. Women might get short-term fat loss, but their metabolism will have been suppressed. It’s not a long-term win. What you want to do is encourage your body to burn more energy and access its fat for energy. I list tracking methods in descending order of usefulness in the book, and the top one is satiety and zest — just feeling better, feeling less hungry. The second one is the menstrual cycle. If your cycle is getting healthier, that’s a good sign. If you’re losing your period, that’s a bad sign.

Lisa: What’s your perspective on plant-based diets and their role in metabolic health?

Lara: I’m an evolutionary biologist by training, so I see everything through that lens. From a basic biology perspective, homo sapiens are generalist omnivores — that’s just a fact. We’ve evolved to have at least some degree of nutrient-dense animal food. As to the amount, that can vary, and I’ll concede that a vegetarian diet that allows eggs and dairy can probably meet some baseline requirements.

But there are key nutrients — including retinol (vitamin A) and vitamin B12 — that are difficult to obtain reliably without animal foods. Some people are genetically much better at converting beta-carotene to vitamin A, and some are not. For people with a slow-converting gene, there’s going to be a hard ceiling on how long they can stay on an exclusively plant-based diet. People might have a honeymoon period where they’re still living off stored nutrients, but at some point, if you can’t make it and you’re not ingesting it, health begins to decline. My clinical observation is that for some people, if they insist on staying fully plant-based, we may have to lower our expectations of how healthy they can be.

Lisa: What are your two key takeaways for listeners who are concerned about their metabolism?

Lara: The first is: trust your body. A lot of my patients feel broken, especially if they’ve tried diet after diet and their body hasn’t responded the way they were told it would. As women, we tend to turn that back on ourselves — we assume it must be our fault. I would say, from 25 years of clinical practice, there’s always a way forward. It may not look like your friend’s trajectory or what you see on social media, but if you’re watching the right metrics — menstrual cycle, energy, stable blood sugar, feeling less hungry naturally — that will lead you in the right direction.

The second takeaway is: what we collectively think of as the normal food supply is not biologically suited to homo sapiens. That’s a tough thing to come to grips with, and it’s not people’s fault. Most of us in the Western world were born into this food environment and we have to consciously shelter from it.