Insulin Resistance: Learn How to Improve Your Insulin Sensitivity to Prevent Type 2 Diabetes.

Every eleventh adult has diabetes, and one in three has prediabetes. Over 95 percent of diabetics have type 2 diabetes (T2D). Half of all U.S. adults—roughly one in three Americans—are known to have insulin resistance, and some estimates put that number as high as 88 percent of adults.

Insulin lies at the heart of diabetes and numerous chronic diseases that plague modern society. Many of your symptoms—including feeling hungry even after a meal, increased or frequent urination, unusual fatigue, and recurrent infections—can be linked to insulin resistance. Let’s take a closer look at insulin and how monitoring it can help prevent T2D.

Like most hormones, insulin is a protein manufactured in one part of the body, travels through the bloodstream, and affects other parts. In insulin’s case, it’s produced in the pancreas, a small organ nestled beneath the stomach. Insulin’s primary role is to regulate blood glucose levels.

When we eat foods that raise blood glucose, the pancreas releases insulin, which then facilitates the transfer of glucose from the blood to various tissues—including the brain, heart, muscles, and fat. But insulin’s influence extends far beyond blood-glucose regulation; it affects every cell in every tissue of the body. This broad reach is unusual among hormones, which typically target only one or a few organs.

The specific effect of insulin varies by cell type. For instance, when insulin binds to a liver cell, that cell produces fat (among other substances); when it binds to a muscle cell, the cell synthesizes new proteins (among other substances). From the brain to the toes, insulin regulates cellular energy use, growth, hormone production, and even cell survival. The common thread among these effects is insulin’s ability to stimulate cells to build large molecules from smaller ones—a process known as anabolism. Insulin is, above all, an anabolic hormone.

What is Insulin Resistance?

Clearly, insulin is crucial—when it functions properly. The issue arises when it doesn’t: a condition known as insulin resistance. At its core, insulin resistance involves a diminished response to insulin, which can stem from various factors. As more cells throughout the body become insulin resistant, the body as a whole is considered insulin resistant. In this state, certain cells require higher-than-normal levels of insulin to achieve the same response as before. Thus, the hallmark of insulin resistance is elevated blood-insulin levels and reduced insulin effectiveness.

Yet amidst this challenge, pathways toward prevention—and even reversal—exist. I firmly advocate for a shift in lifestyle, recognizing its profound impact on mitigating the risk of insulin resistance and, in some cases, eradicating it entirely. Committing to altered exercise routines or dietary habits doesn’t offer the immediate gratification of a pill or the swift results of bariatric surgery, but it presents a holistic approach that addresses root causes rather than merely treating symptoms.

While genetics and environmental factors may seem beyond our influence, the truth remains that for the vast majority—including each individual reading this—you wield considerable power over your lifestyle choices. Even when genetic predispositions aren’t in our favor, lifestyle adjustments are our most potent tool. The two essential components of lifestyle that influence the risk of insulin resistance are movement and diet—that is, exercise and nutrition. Another crucial aspect is detoxifying your external environment and your cells. Here is The Ultimate Guide for Toxin Free Living.

How to Measure Your Insulin?

Before embarking on any health journey, I recommend assessing your current status so you can track progress and take responsible action.

To gauge your risk level, start by answering these questions:

• Do you have excess belly fat?

• Do you have high blood pressure?

• Do you have a family history of heart disease?

• Do you have elevated blood triglyceride levels?

• Do you retain water easily?

• Do you have patches of darker-colored skin or small skin bumps (skin tags) around your neck, armpits, or other areas?

• Do you have a family member with insulin resistance or type 2 diabetes?

• Do you have polycystic ovarian syndrome (PCOS) or erectile dysfunction (for men)?

All of these questions hint at a connection to insulin resistance. If you answered “yes” to one question, you likely have insulin resistance. If you answered “yes” to two or more, you almost certainly have it.

However, don’t dwell solely on these symptoms. While observing and tracking symptoms can be helpful, they merely indicate your general insulin sensitivity. If you intend to reverse or prevent insulin resistance through lifestyle changes, you need to measure your insulin levels.

First, let’s address why I recommend measuring insulin rather than Hemoglobin A1C (HbA1c). HbA1c reflects average blood glucose levels over the past 90–120 days. Glucose binds to the hemoglobin inside red blood cells if not used immediately, contributing to HbA1c levels. Unlike fasting blood glucose, which measures glucose at the time of testing, HbA1c provides a snapshot of glucose over several months. Many clinicians rely solely on HbA1c for type 2 diabetes screening due to its convenience. However, by the time HbA1c levels rise significantly, individuals have likely already developed substantial insulin resistance and pancreatic beta-cell dysfunction.

Research suggests that insulin resistance precedes the development of type 2 diabetes. In an attempt to maintain glycemic homeostasis, beta cells increase insulin secretion to lower blood glucose. However, this increased workload eventually leads to beta-cell failure, resulting in impaired glucose tolerance (IGT) and, ultimately, type 2 diabetes. Identifying prediabetes before marked beta-cell dysfunction occurs increases the opportunity for remission or delayed progression. This pathophysiology indicates that fasting insulin levels can identify insulin resistance long before plasma glucose and HbA1c levels rise.

Various blood tests measure fasting and non-fasting insulin levels. Personally, as an FDN-P, I recommend the Salivary Advanced Stress and Hormone Profile by FLUIDS iQ. This test combines two flagship hormone and metabolic panels to provide insights into hormonal and immune balance, chronic stress, stress-related disorders, and signs of metabolic syndrome—an imbalance that includes elevated blood pressure, high blood sugar, excess waist-circumference fat, and abnormal cholesterol or triglyceride levels. It analyzes diurnal cortisol (AM, noon, afternoon, bedtime), DHEA-S, the cortisol:DHEA-S ratio, estradiol, progesterone, the estradiol:progesterone ratio, testosterone, secretory IgA (SIgA), daytime melatonin, and fasting and non-fasting insulin.

Ideally, you should frequently check your blood glucose. Your fasting insulin should be below approximately 6 µU/mL. While the average for men and women is around 8–9 µU/mL, it’s not ideal to be “average” in this case—a person with 8 µU/mL has double the risk of developing type 2 diabetes compared to someone with 5 µU/mL.

If measuring insulin isn’t feasible, there are alternatives:

1. Monitor your blood pressure. Lower insulin levels should lead to decreased blood pressure within a few days.

2. Measure your ketones. By using a ketone meter, you can indirectly assess insulin control, since ketone levels rise as insulin levels drop. This may take a few days. Ketones are produced by the liver when the body burns fat for energy. Most are used by the body—especially the brain—but some are expelled in breath and urine. Many people find it motivating to measure ketones to gauge insulin changes. When blood ketones are around 1 mM, insulin levels are likely below 10 µU/mL, an excellent starting point. However, as you continue, ketones may rise slightly even if insulin levels don’t drop much further. Until at-home insulin testing is available, this is the easiest DIY method.

   
   

Where you begin depends on your current status:

• Low insulin (< ~6 µU/mL or 41 pmol/L): You’re likely doing well, with strong insulin sensitivity—either due to smart lifestyle choices or youthful resilience.

• Moderately elevated insulin (7–17 µU/mL or 48–118 pmol/L): Start making changes, particularly to your diet.

• High insulin (> 18 µU/mL or 125 pmol/L): Make changes immediately; adjust your eating habits at your next meal.

Eating to Keep Insulin Low

As you embrace nutritional changes to become more insulin-sensitive and help control your health, every aspect of your diet—what you eat, when you eat it—is a means to that end.

Here are four vital pillars that provide the foundation of a smart plan:

• Control Carbohydrates.

• Prioritize Protein.

• Fill with Healthy Fats.

• Watch the Clock.

Control Carbohydrates

This is the first and most fundamental principle for rapidly and effectively controlling insulin. Due to inherent metabolic differences among all people, it simply isn't possible to establish a one-size-fits-all strategy. Your ideal composition of macronutrients (that is, the percentage of calories from fat, protein, and carbohydrates) can vary, but no matter what ends up being the right balance for you, carbohydrates will constitute a far smaller part of the diet than is typical in the conventional and ubiquitous "Western diet" (which is typically ~50%-60% carbohydrates). And that's a good thing—we're looking to reverse the trends this diet brought on.

Adapted from Nutall, F.Q. and M.C. Gannon, Plasma glucose and insulin response to macronutrients in nondiabetic and NIDDM subjects. Diabetes Care, 1991. 14(9): p. 824-38.

Remember that while carbohydrates trigger a robust insulin response (though there’s a broad range—broccoli has little effect, whereas potato chips have a large effect), protein has a modest effect, and dietary fat has none. With this in mind, here are some general macronutrient ranges (percentages of calories from fat, protein, and carbohydrates) to consider when planning a nutrition plan to improve or prevent insulin resistance.

If your insulin levels are high, aim for roughly 70% of calories from fat, 25% from protein, and 5% from carbohydrates—generally fewer than 50 grams of carbs per day.

Keep in mind that these ranges may require individual optimization; they’re not set in stone. Eating fewer than 50 grams of carbohydrates per day is very likely to induce ketosis for most people. If you’re uncomfortable with that and feel you need more carbohydrates, focus on low–glycemic-load vegetables and fruits.

One thing to remember: you don’t need to remain in ketosis constantly to enjoy the insulin-sensitizing benefits of a carbohydrate-controlled or “smart-carb” approach. You can learn more about smart carbs in this post.

Here are some Insulin-Friendly Fruits and Vegetables (average serving size, 100 g):

Insulin-Friendly Fruits and Vegetables	Fats (g)	Net Carbs (g)	Protein (g)
Cabbage	0	6	2
Cauliflower	0	6	5
Broccoli	1	7	5
Spinach	0	1	3
Romaine Lettuce	1	2	2
Bell Pepper	0	5	1
Green Beans	0	4	2
Onion	0	12	2
Blackberries	1	8	2
Raspberries	1	8	2

Hence, strict glycemic control is necessary. I often suggest my clients Continuous Glucose Monitors (CGM) for educational purposes. A continuous glucose monitor (CGM) is a device that measures glucose levels in the interstitial fluid (fluid between cells) under the skin. It provides continuous real-time data about glucose levels throughout the day and night. CGM systems use a small sensor inserted under the skin, which measures glucose levels every few minutes and transmits the data wirelessly to a receiver or smartphone. CGMs are emerging tools in the management of type 2 diabetes.

Remember the general guidelines for using the glycemic load:

• Be starch-smart! Carbohydrates are an incredibly diverse macronutrient, and the more natural the carbohydrate, the better. A general rule to help avoid the worst of the carbohydrates is that if it comes in a bag or a box with a barcode, it's likely a carbohydrate to avoid.

• Don't drink your carbohydrates.There is a big difference in insulin response when we drink a fruit compared with eating the fruit. When we've removed or altered the fiber in a fruit, we're getting the pure fructose as opposed to fructose with an appropriate amount of fiber. This presence of the natural fruit fiber dramatically reduces the insulin response to the fruit. Moreover, fiber plays an important role in your gut health, find more in this post.

• Where you're able, make an effort to focus on more fermented carbohydrates! Including raw sauerkraut or kimchi with a meal daily. Similar benefits may be seen with fermented ginseng and soybeans. For those who get almost no fermented foods and don't plan on altering their cuisine enough to include them, one easy strategy is to drink apple cider vinegar every day. Whichever is your most carbohydrate-heavy meal of the day, precede that meal with 1 to 2 tablespoons of raw, unfiltered (like Bragg's) apple cider vinegar.

• Don't be so sweet! Mostly, this recognizes that sugar is ubiquitous in its many forms. Whether it's "cane sugar," "evaporated cane juice," "high-fructose corn syrup," "brown rice syrup," or others, they're all the same garbage. You can find sugar-free versions of the most common foods in your home, paying particular attention to things like sauces, dressings, ketchup, peanut butter, and so forth.

  
  

• Choose the right Artificial Sweeteners. Thanks to countless non-nutritive sweeteners, it's possible to enjoy something sweet without spiking glucose and insulin. Be careful with how you buy your sweeteners if you plan on using them for baking or cooking. In general, if the sweetener comes in a powder, it can contain glucose-heavy fillers, such as maltodextrin, defeating the purpose of the sweetener, which is to not spike insulin. Here's a list of sweeteners and how they affect insulin:

Sweetener	Insulin effect alone	Insulin effect with carbohydrates
Sucralose	None	Increased
Aspartame	None	Unclear, possibly increased
Stevia	None	None
Acesulfame-K	Unclear, possible	Unclear, possibly increased
Xylitol	Little	Little
Erythritol	None	None
Other sugar alcohols	Variable, likely	Variable, very likely increased
Monk fruit extract	None	None

Prioritize Protein

Avoid the temptation to eat too little protein; one concern as people adopt a low-carbohydrate, high-fat diet is that they excessively eschew protein (such as meat or eggs). Protein is not just a single macronutrient but the delivery system for twenty amino acids. While certain amino acids (the components of dietary protein that circulate in the blood) can cause an insulin release, the degree to which this occurs depends heavily on the amount of glucose in the blood, whether the person is ingesting carbohydrates with the protein, or has underlying elevated blood glucose (i.e., hyperglycemia). If carbohydrate consumption and blood glucose are low, there will be little or no insulin response to dietary protein. In contrast, if carbohydrate consumption is high and blood glucose is elevated, there will be a substantial insulin response. Find more information about essential macronutrient Protein in this post.

To optimize muscle and bone growth and recovery from exercise, aim to get 1 to 1.5 grams of protein per kilogram. Critically, if you're older, you need to be on the higher end of this; we become progressively less capable of changing dietary protein into muscle protein as we age.

Balanced Protein Distribution:

• Breakfast: ⅓ of your daily dose, should be around 20-30g Protein, but calculate according to your weight.

• Lunch: ⅓ of your daily dose

• Dinner: ⅓ of your daily dose

These three meals should satisfy you, and you should not snack in between. But if you want some additional fuel between your main meals, take Dark Berry Protein with unsweetened Macadamia milk and Super Amino 23 by Purium - a healthy source of protein and highly bioavailable amino acids.

Be careful with cured meats, including sausages and especially jerky; these very often include significant amounts of sugar. And don't shy away from fatty meats and fish, including lamb and salmon.

Here's a list of ideal protein sources and their nutritional breakdown (based on a conventional serving size of 4 oz. or 115 g):

Protein	Fats (g)	Net Carbs (g)	Protein (g)
Ground beef (80/20)	23	0	20
Ribeye steak	25	0	27
Bacon	51	0	13
Pork chop	18	0	30
Chicken thigh	20	0	17
Chicken breast	1	0	26
Salmon	15	0	23
Ground lamb	27	0	19
Large egg	5	0.5	6
Tofu	3	2	7
Tempeh	9	9	15
Pumpkin seeds	42	4	32

Here's a list of good diary choices (average serving size of 100g or ½ cup):

Dairy	Fats (g)	Net Carbs (g)	Protein (g)
Greek yogurt	1	1	3
Cottage cheese	1	1	4
Mozzarella	5	1	5
Aged cheddar	9	0	7
Parmesan	7	1	10

Fill with Healthy Fats

Embrace the insulin-sensitizing value that comes from eating real foods with all their glorious fat. Remember that the fat we eat does not increase insulin and is thus a useful food that can nourish your body while not feeding the "beast" (i.e., insulin resistance). In fact, be wary of meals that don't include fat; they won't be as satisfying, and the insulin effect of the meal will very likely be higher than it would otherwise be. We have a physiological need for healthy dietary fat—it is essential. Find information about healthy fats in this post.

A note on nuts: Like dairy, nuts tend to be higher in all three macronutrients, albeit heavier in fat. Nevertheless, there is a spectrum of carbohydrate content in nuts worth noting:

• Lowest carbohydrate: macadamia nuts, pecans

• Moderate carbohydrate: This includes most nuts, including peanuts, almonds, and walnuts.

• Highest carbohydrate: pistachios, cashews

Here's a specific list of good ones (based on average serving sizes of 2 oz. or 60 g):

Nuts	Fats (g)	Net Carbs (g)	Protein (g)
Macadamia nuts	43	3	4
Brazil nuts	37	3	8
Pecans	41	3	5
Almonds	28	5	12
Hazelnuts	36	3	9

Watch the Clock!

The most important and simple concept to keep in mind is that having prolonged periods during the day where glucose and insulin are low is a vital step in the right direction.

I recommend adopting a basic strategy of time-restricted eating:

• Fast from food (not water!) for 12 hours every night. Usually, this will take the form of eating dinner around 5-7 PM and not eating again until 5-7 AM or so. It is easy, and natural.

• Two to three days per week, extend this to an 18-hour fast (e.g., eat dinner at 6 PM and eat your first meal at noon the next day). Not a big deal as well. If your meals are higher in fat and lower in refined carbohydrates, you'll be surprised at how easy this becomes as your body adapts to using fat, including your own body fat, as a fuel, something that can happen as insulin is kept under control.

• Every two to four weeks, you can even go all the way and fast from food for 24 hours. Keep in mind that for cycling females, fasting as well as a low-carb diet during the luteal phase is not recommended, as it can harm hormones. The luteal phase is the time between ovulation and bleeding. 

Dining Out

Even at good restaurants, they sometimes add ingredients to meals that you may want to exclude. Some questions you should not be embarrassed to ask:

• Dear Chef, I have food allergies to vegetable oils. I must avoid all items containing the following oils: Canola Oil, Corn Oil, Cottonseed Oil, Sunflower Oil, Grape-seed Oil, Safflower Oil, Rice Bran Oil, Soybean Oil. Please substitute with: Avocado Oil, Olive Oil, Coconut Oil, Ghee, Duck Fat, Beef Tallow, Lard, or Butter.

• Can you omit MSG or other additives from my meal?

• Is the beef grass-fed and antibiotic-free?

• Is the fish wild-caught?

• Can I have the dish baked instead of fried?

• Are the vegetables locally sourced?

Stay Hydrated

I follow the "8x8 rule," which means drinking eight 8-ounce glasses of water per day, totaling about 2 liters (64 ounces). To one of the glasses I add H2 ELITE® by Quicksilver Scientific, use promo code SMILA for a discount.

Movement Matters

Exercise is very helpful for improving insulin resistance. In fact, any kind of physical activity can help combat insulin resistance because it removes glucose from the blood without involving insulin.

As mentioned at the beginning, insulin opens the doors to escort glucose from the blood to various parts of the body, such as the brain, heart, muscles, and fat tissue. Our bodies rely on insulin to usher glucose from the blood into these tissues and get our levels back to normal. In fact, this clearance process is so vital that the main glucose consumers, our muscles, can get the glucose for themselves.

To move our body in any way, we must contract (flex) muscles. Interestingly, as muscles contract, they can take in glucose from the blood without using insulin. (As an aside, there is a myth that muscles use only glucose for energy. Muscles can indeed use other fuel sources, like fat or ketones, perfectly well). This means that even if a muscle is resistant to insulin, it can still pull glucose from the bloodstream when contracting. Because movement enables this insulin-independent process, our blood insulin naturally lowers during and shortly after exercise. In fact, just moving is so helpful that the body becomes more insulin sensitive even in the absence of any weight changes.

Other than muscle contraction and the insulin-bypass process involved with it, exercise appears to improve insulin sensitivity by easing many of its causes, such as central obesity, oxidative stress, inflammation, and more. One study had insulin-resistant individuals engage in moderate-intensity walking for three months.

Even over the course of the relatively brief study, the people lost an average of 2% body fat, which appeared to largely come from visceral fat. A 2% change isn't much, yet it was still enough to improve participants' insulin sensitivity. Moreover, another study found that a three-month exercise intervention reduced markers of inflammation and oxidative stress in the absence of weight loss. Regular and even light exercise can also improve sleep and may reduce markers of stress.

Another interesting aspect of exercise as an intervention to improve insulin resistance is that it works across all ages and sexes. In one study, just 16 weeks of regular exercise not only improved strength by almost 50% in men aged 50 to 65, but also increased their insulin sensitivity by over 20%. This was in the absence of any changes in diet—they just started exercising.

Aerobic Versus Resistance Exercise

To run (or bike or swim) or lift—that is the question. If you have time, you can certainly do both aerobic and resistance exercise; you'd experience more robust improvements than you would doing either cardio or weight training alone.

But in the end, most of us devote our limited hours only to the activity that yields the greatest benefit. The overwhelming majority of research has explored the issue of exercise and insulin resistance in the context of aerobic exercise alone.

However, plenty of studies have indeed confirmed that doing resistance exercise, even just twice per week, is enough to improve insulin sensitivity. All of this serves to strengthen the role of regular exercise in fighting insulin resistance. Studies that have compared the insulin-sensitizing effect of both aerobic and resistance exercise reveal that, minute for minute, resistance training may be superior in improving insulin sensitivity.

One study tracked roughly 32,000 people for almost 20 years and found that engaging in either aerobic or resistance exercise for 2.5 hours per week yielded similar improvements, but that resistance training was superior when the participants spent less time engaging in exercise.

So, if you have only one hour in a week to exercise, resistance training will have a higher return on investment. This is very likely a result of the respective changes in muscle mass that accompany each type of exercise; resistance training increases muscle mass while aerobic does not.

The average individual muscle is the largest organ in the body; muscle is also the largest destination for insulin-stimulated glucose uptake. If we have more muscle, we have a greater area into which we can deposit glucose from the blood, thus lowering blood insulin.

Body Weight - Not the Whole Story

Certain studies show greater improvements in body weight with aerobic exercise over resistance exercise. Of course, a lot depends on how long the study subjects exercise, which varies greatly between studies, but the larger problem with such conclusions is that body weight is not an indicator of body composition. Muscle weighs more than fat. Inasmuch as resistance exercise increases muscle mass more than aerobic exercise does, this naturally affects body weight.

To sum this up: the best exercise is the one you'll do. There is certainly value in challenging yourself to do something you're not familiar (or even comfortable) with. However, if your dislike for one form of exercise is substantial enough that committing to it would mean you stop doing anything, stick with something you know you'll do. Just do it harder.

How Often, How Long, and When Should I Exercise?

If you're able, you should engage in physical activity six days per week, reserving one day for genuine rest to allow the body to recover. Depending on the type of exercise, the daily routines would need variety to prevent overuse injury and ensure proper recovery of specific muscles. I consider 20 minutes to be just enough time capable of eliciting a pronounced benefit. Where time is limited (~20 minutes), the intensity of the activity is more important. When possible, 30 to 40 minutes is a good length of time to be certain you fully complete the day's exercise regimen.

The time of your exercise session during the day is less important than just getting it done; there is no clear benefit to exercising in the morning versus the afternoon versus the evening. However, people who exercise in the morning usually find fewer excuses and are therefore more consistent. The reality is that fewer things can potentially get in the way of exercising at 6 AM compared to 6 PM.

How Intense Should My Workout Be?

Your exercise intensity may matter more for improving insulin sensitivity than any other variable, including duration. An important caveat: Do not try to do more than you're capable of. When implementing high-intensity training, it is essential to start easier, let your body adapt, and gradually work up to higher intensities.

For aerobic exercise, high-intensity workouts are achieved by simply performing the exercise more vigorously. An ideal way to do this is interval training, where one minute of lower intensity exercise is followed by a minute of maximal intensity, repeated for the desired duration. So, for example, if you choose to run, don't just set your watch for 35 minutes and jog away happily. Rather, keep your eye on your watch to mix intervals of light jogging with periods of heavier running.

For resistance exercise, you can achieve higher intensity by performing every set to failure. In other words, every time you begin an exercise, you continue that exercise until you can't do any more, regardless of the number of repetitions. Similar to high-intensity aerobic exercise, it's truly exhausting, but it is essential to reaping the maximum insulin benefit. In fact, just a few exercises performed one single time to failure can be enough to improve insulin resistance.

After reading this, you might conclude that the mantra is "go often and go hard." A better takeaway would be "just do it"—start where you are by doing what you can. If you're honest with yourself, you'll make sure you're regularly increasing either the frequency or intensity to help maximize the insulin-sensitizing effect of your efforts. Whatever you decide, and as effective as exercise can be at fighting insulin resistance, it's best matched with changes in what and when we eat.

Think Before You Drink

If your reason for exercising is to improve your metabolic health by improving insulin sensitivity, put down the post-workout sports drink—it's making things worse.

Exercise is a good way to improve insulin sensitivity. However, by adding a glucose load after your workout, which many believe is essential, you lose some of the insulin-sensitizing improvements of the exercise. The best bet is to avoid sugary drinks and food for as long after the workout as you're comfortable.

Sending Optimal Health & Ultimate Wellness, 

Julia Smila - FDN Practitioner & Pranic Healer