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Bye!

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Hey everyone, Mikki here. You're listening to Mini Mikkipedia on a Monday. And today I wanna chat about insulin. Last week, I delved into cortisol and whether or not we should be concerned with cortisol spikes. And so I thought I would continue the theme, thinking about metabolism, thinking about our metabolic health and dive into insulin today. This is clearly a topic which I've spoken on in different...

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both in the long form interviews that I do and on other mini-micropedias, but I just want to give big picture perspective on the role of insulin, when it goes wrong, how to know if you're insulin resistant, and what are some pillars that you need to think about in order to resolve or reverse the condition. So insulin is an essential anabolic hormone, meaning that it helps build and maintain tissues in the body.

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Without insulin, we cannot survive. It plays a fundamental role in energy storage and blood sugar regulation. But of course, its importance goes well beyond that. Insulin helps regulate glucose levels in the bloodstream by allowing sugar to enter the cells for energy. It promotes muscle growth by facilitating amino acid uptake, and in fact, insulin is also known as the storage hormone. So it takes all of the fatty acids

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the glucose and our amino acids and delivers them to where it needs to be. Incident supports a healthy reproductive system, playing a role in estrogen and progesterone balance in women. It is crucial for fertility and reproductive health in both men and women. And in women, insulin helps regulate ovulation and interacts with luteinizing hormone and follicle stimulating hormone, which are necessary for proper menstrual cycles.

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can disrupt ovulation leading to irregular cycles and contributing to conditions like polycystic ovarian syndrome, which is a major cause of infertility. And of course, PCOS is driven more than just by insulin resistance. There are four different types potentially of PCOS, but the most common one does have that insulin resistant background.

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In men, insulin helps maintain testosterone balance. So when insulin resistance occurs, it can lead to lower testosterone levels, reduce sperm quality, and an increased risk of erectile dysfunction. More so because of the lack of blood flow to the penis, as I mentioned in the erectile dysfunction episode I did several weeks ago. You need really good blood flow when it comes to all things related to an erection.

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and if you are unable to get that blood flow through because of high insulin levels that lead to hypertension, that's an issue. Managing insulin sensitivity can thus have profound effects on fertility, hormone balance and overall reproductive health. Insulin is, however, often misunderstood as being always the villain, primarily because it is associated with weight gain and metabolic dysfunction when its signaling becomes impaired.

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And that's where the issue lies. It's not insulin itself, it's insulin resistant that causes the problem. So just to remind you, when we eat particularly carbohydrate-based foods, we get an insulin response. So when the carbohydrate is broken down, insulin is released to take that glucose and store it for later use. But as I mentioned, it isn't just glucose that it stores, it's also storing fatty acids, it is also storing protein.

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And the insulin responds most predominantly to carbohydrate-based foods, but you still get an insulin response to fat and to amino acids. The degree of this is far lower than to carbohydrate, but if you remember in my podcasts I've done with Mali Kendall, we talk about that insulin response to fat, which people forget about. And of course, there are some amino acids, which certainly have more of an

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anabolic effect or drive insulin up. But insulin is only problematic when the cells stop responding effectively to it. And this leads to a condition called insulin resistance. So this is a major driver of metabolic disorders, including type 2 diabetes, metabolic associated steatosis, which is fatty liver disease, and obesity. It is also implicated in neurological conditions like Alzheimer's and dementia.

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People often refer to those conditions or Alzheimer's as type 3 diabetes, which as I understand it, not all of the metabolic experts really love that term for it. But at any rate, high blood sugar, high insulin levels are associated with neurological issues, particularly later in life. So when insulin resistance develops, the pancreas produces more insulin to compensate, leading to hyperinsulinemia.

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chronically high insulin levels. Cells in the liver, the muscles and the fat become less responsive, leading to a buildup of glucose in the blood. The body stores more fat, particularly in the liver and the abdominal region, so that visceral fat. And insulin fails to regulate hunger properly, so this leads to increased cravings for sugar and carbohydrates. When insulin is doing its job properly, just as sort of sidebar,

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It actually helps regulate appetite and satiety and you can feel fuller. And this is a good thing, but it's when this insulin resistance starts to go, starts to increase that it can really impact negatively on, on our cravings. Blood sugar swings contribute to reactive hypoglycemia. And this could mimic symptoms of food addiction also. But if you could think of things like shakiness, irritability, brain fog and cravings, these all occur.

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when we have these energy crashes or reactive hypoglycemia. And we seek out fast energy, which is often in the form of sugar and caffeine. So what causes insulin resistance? There are quite a few factors, and I'm going to go through them, albeit these are in of themselves, these could be deep dive topics. So excess calorie intake in processed foods, no surprise there. Consistently eating more calories than the body requires,

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particularly from highly processed foods rich in refined carbohydrates and sugars, can overload insulin pathways. This leads to excessive insulin production, gradually causing the body's cells to stop responding efficiently to insulin. Oxidative stress and inflammation can also cause insulin resistance. Chronic inflammation damages insulin receptors, making it harder for cells to absorb glucose. High oxidative stress, driven by poor diet.

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and chronic stress creates free radicals that impairs insulin function. Elevated cortisol levels from prolonged stress, as I discussed last week, directly contributes to insulin resistance by increasing blood sugar levels. Similarly, inadequate sleep disrupts the body's metabolic processes, reducing insulin sensitivity and increasing hunger hormones. Even a night of sleep deprivation, less than 5 hours sleep, makes the body insulin resistant.

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Sedentary lifestyle and lack of exercise. No surprise here. Movement, particularly resistance training and regular physical activity, plays a crucial role in glucose uptake. Inactivity reduces muscle insulin sensitivity, leading to excess glucose circulating in the bloodstream. Certain medications, including antidepressants, corticosteroids, beta blockers, and some hormone contraceptives can impair insulin function and contribute to metabolic dysfunction. Some individuals are more prone to insulin resistance due

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resistance due to their genetic makeup. Don't forget though that genes load the gun but diet and lifestyle pull the trigger so just because you might have genetics that predispose you to being insulin resistant doesn't mean that you're necessarily going to have it. The gut microbiome imbalances. So an unhealthy gut microbiome can contribute to systemic inflammation and metabolic dysfunction. This worsens insulin resistance.

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Fat cells reaching storage capacity. So when adipose fat cells become overly filled, they experience hypertrophy, so they expand in size. This can lead to insulin resistance, which means they become less responsive to insulin signal to take in more glucose and fatty acids. As a result, excess energy spills over into the bloodstream in the form of elevated free fatty acids and glucose, contributing to

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systemic insulin resistance and metabolic dysfunction. And there is also physiological insulin resistance. Temporary insulin resistance can occur under specific physiological conditions. If you are following a low carbohydrate diet, the body adapts by reducing insulin sensitivity to prioritize, well, one to prioritize fat metabolism, but

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also to make sure that the glucose that you do have is directed to the cells that actually need it, such as the red blood cells and the retina, and potentially the brain as well. Similarly, during pregnancy, insulin resistance naturally increases to ensure glucose availability to the growing foetus. These are normal adaptive responses and are not necessarily pathogenic or problematic unless they're compounded by other metabolic issues.

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So one of the biggest misconceptions is that normal fasting glucose levels mean that insulin resistance isn't present. However, blood sugar can remain normal for years while insulin levels are rising in the background. And this is the problem actually when you go to your doctor and they measure your HbA1c, which is a long-term marker of blood sugar control, by long-term I mean in the last 10 to 12 weeks. And if you fall under the arbitrary cutoff of 40.

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here in New Zealand for units, you're fine, apparently. But there's no investigation as to what's going on in the background to keep your levels within that quote unquote normal range or below that sort of cutoff level. Now, I say it's arbitrary because it doesn't mean that right up until 40 for your HbA1c you are healthy and then at 41 you're pre-diabetic. In fact, people would argue that your HbA1c is much

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better to be at 30 to 33 or below rather than high 30. So just bear that in mind when you get your A1C marker tested, albeit we have no idea what's going on in the background with your insulin and that is an issue. So fasting insulin test, this is either measured in micro international units or picomoles per liter. One micro international unit is worth six picomoles, just so you know.

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So a test of under eight is considered optimal or 48. A test of between eight to 12 is mild insulin resistance. A test between 13 to 17 is moderate insulin resistance. And a test over 18 is severe insulin resistance. And just times those numbers by six to get the Pecumols for units that are relevant for sort of North America. You also can test something called HOMA-IR.

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And this uses fasting insulin and glucose to assess insulin sensitivity and a ratio of over 1.0 indicates insulin resistance. Oral glucose tolerance test with insulin measurements. So you do some standard glucose test where you take on board 50 to 75 grams of carbohydrate and they look at your glucose response over two hours. If you also have an insulin clamp with that, it can tell you what your insulin response is doing. That's not a... I mean...

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OGTT isn't necessarily a commonly run test anyway. It's quite intensive, takes a lot of time, costs a bit of money. To throw an insulin clamp on top of it is even less likely to be run, but this is another way. Also, waist circumference and imaging tests. So women with a waist circumference over 85 centimeters and men with a waist over 100 centimeters does suggest visceral fat accumulation.

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A DEXA scan or MRI can provide a bit more of a precise breakdown of visceral versus subcutaneous fat, albeit they do have a, there are limitations to everything, right? However, well, I do just want to note that while testing insulin levels can seem really useful, there are some people who have to take issue with them actually. If you remember, I did an interview with Dr. Ted Naiman. He is not a fan of testing for fasting insulin.

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And the reason for this is because it can be really variable. So insulin levels will fluctuate throughout the day, making it challenging to interpret a single test result accurately. So if you eat late at night, if you fast like 16 hours before your test, if you eat a lot of carbohydrate, or if you eat a lot of fat, all of these things can impact on what the reading is for fasting insulin. So...

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I would think that you would want to get that fasting insulin measured under standard conditions and do a few of them to get an average. Also of course though, not everyone can afford an insulin test, it may not be available, albeit you can always ask your doctor and you get its user pays. So some alternative markers then would be your triglyceride to HDL ratio on a standard cholesterol panel. A ratio above two is a strong indicator of insulin resistance.

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Fasting blood sugar in A1C, as I mentioned, that does suggest chronic blood sugar dysregulation if they're really high, although I just talked before about some of the issues with those. You can get something called a C-Peptide test. The availability of this also varies and it isn't a standard test, but it may be useful for assessing insulin production and distinguishing between diabetes types. It measures insulin production and can indicate whether the body is overproducing insulin.

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Toast meal blood sugar response using a continuous glucose monitor or a blue committer can help identify how the body responds to carbohydrates. Another visual marker of insulin resistance, skin tags and acanthosis nigrigans, might have said that wrong, which basically these are darkened velvety skin, often in body folds such as the neck, under the arms or groin.

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associated with insulin resistance, and it's a visible sign that metabolic health may be compromised. So with all of that in mind, what are the big picture things for reversing insulin resistance? Because you can absolutely do that. And in most cases, this is through lifestyle interventions. First and foremost, build muscle. Muscle is your metabolic organ. It is one of the biggest reservoirs for storing glucose in the body.

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The more muscle you have, the more storage capacity you have for the breakdown product of carbohydrate to be stored for later use and not be hanging around your bloodstream. Increasing muscle mass improves insulin sensitivity and allows for better glucose clearance. It is worth noting that exercise itself increases insulin sensitivity. So there are transporters, glucose transporters that don't require insulin.

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to take carbohydrate in. That's why actually one of the best times to eat carbohydrate is post-exercise because you do not have to rely on insulin to do the job for you. Resistance training lowers insulin levels and enhances mitochondrial function and of course builds muscle. And the more muscle you have, the more metabolically flexible you are. Managing stress and inflammation, I think, are really critical. And if you have systemic and chronic inflammation,

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then reducing that inflammation can reverse insulin resistance. That then makes you able to tolerate more carbohydrate. You can't really have a high carb diet and expect that your insulin resistance will resolve. But if you target inflammation, if this is the cause of the issue, then this is going to help increase your tolerance. So chronic stress elevates cortisol, which drives blood sugar imbalances.

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inflammation impairs insulin signaling and therefore foods which target the inflammation and strategies to target inflammation such as dark leafy greens, omega-3 fatty acids, antioxidants, protein-based foods, removing the highly refined carbohydrate, having a low carb approach is all going to help counteract this.

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And I mentioned before about the gut microbiome, like actually working on a healthy gut microbiome to influence insulin sensitivity, adding in things like kefir, sauerkraut, a probiotic and rotating through these probiotics, these can all be super helpful. In addition to removing foods that you might be sensitive to that would trigger an inflammatory or immune response. Things like gluten and dairy and other components of foods, which

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create stress for the body. I mean, it goes without saying, optimizing nutrition is key. In a low carbohydrate diet, so reducing your carbohydrate intake, particularly refined carbs, absolutely improves insulin sensitivity and reduces insulin resistance. This can also help restore metabolic flexibility, allowing the body to utilize fat as an energy source while decreasing insulin demand. What I would say here as well, or to remind people, is that when we hit

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perimenopause as females, we become less insulin sensitive. So everything I'm sort of talking about here, if you have experienced unwanted weight gain, issues with energy regulation, then the insulin resistance is likely to be part of your bigger metabolic health picture. Protein intake, as you know, it stabilizes blood sugar, reduces cravings, including a good amount of

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fats in your diet such as omega-3s, olive oil, avocado, nuts and seeds. This can help improve insulin function and you'd want to include as much as you can from a calorie budget perspective so you're able to maintain a healthy weight. Certain supplements such as magnesium, vitamin D, and alpha lipoic acid support insulin signaling and mitochondrial function.

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Other things like having raw apple cider vinegar before a meal helps lower that glucose response can also be really helpful. Reducing obviously those refined sugars, which I've already discussed, and reducing alcohol if you're insulin resistant, I think is also really important as well. And of course, move more, especially like, so you've got both high intensity activity and low intensity activity. And with the low...

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intensity activity, it's super interesting actually, the calves play a unique role in glucose disposal. So they contain a high density of slow-twitch muscle fibers, which are highly insulin sensitive and continuously active when we stand, walk, or move. So even light movements like standing on your toes, performing calf raises, and walking will stimulate the glucose uptake independent of insulin. And this is actually a clinically significant

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reducing metabolic strain, improving insulin sensitivity over time. And walking post meal we know can really help. So 10 to 15 minutes after you've eaten changes that blood sugar response to the meal. But just movement in general, walking, standing, stretching helps regulate blood sugar. Non-exercise activity thermogenesis, which is exercise we do outside of structured activity. Small movements like fidgeting or standing can significantly impact metabolism.

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albeit if you're not someone that is a fidgeter, making conscious decision to get up and move around is super important. Exercise just in general improves insulin sensitivity. And if you are sleep deprived and which makes you insulin resistant, one of the things that you can do is in fact get up in the morning, do a fasted training session, which might be 45 minutes of steady state or do a hip-based session, which might be, you know, 20 minutes.

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go high intensity, not only will that help you sort of wake up, but it helps regulate blood sugar across the day. Also a 2023 study found that performing body weight squats every 45 minutes significantly reduce postprandial, post meal blood sugar spikes. So this does demonstrate the impact of brief intermittent movement throughout the day. And of course prioritizing sleep and circadian health. So

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aiming for that six and a half to nine hours of quality sleep, having really good sleep hygiene and I've got a sleep expert coming on in a couple of weeks to discuss this to remind us all what this looks like. And morning sunlight exposure supports healthy circadian rhythms and insulin function. So insulin is essential for life, but its dysregulation can lead to chronic health problems. And so the key to metabolic health is maintaining insulin sensitivity.

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and all of the things that I talked about here allow you to do that. Now I did mention a little bit in here, visceral fat, fat cell hypertrophy, and I'm going to dive more into them in the next mini-micropedia because it's a super fascinating area of conversation or discussion. So if you've got any tips and tricks or any questions, feel free to reach out to me. I'm on Instagram, threads and Twitter at mikkiwilliden, Facebook at MikkiwillidenNutrition.

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get to my website, mikkiwilliden.com and book a one-on-one call with me there. All right, team, you have the best week. See ya.