All you need to know about insulin resistance

Written by Dr Marissa Kelaher, Graphics by Dr Taisia Cech

Insulin resistance is a term that’s being talked about a lot these days - in relation to everything from weight gain, to menopause, hormonal health, heart disease and more.

But what does it ACTUALLY mean, how can you know if you have it, and most importantly what can you do about it?!

In this blog post we’ll take a dive into what insulin resistance is; what causes it; what signs to look out for; and what lifestyle strategies you can take to help improve, or even reverse it!!


WHAT DOES INSULIN RESISTANCE MEAN?

Insulin resistance is a complex disorder of metabolism, where cells in our body become less responsive to insulin, leading to elevated insulin levels, and eventually elevated blood sugar levels.

It is caused by a number of different factors, including genetics, obesity, diet, a sedentary lifestyle, and inflammation.

Insulin is a hormone produced by our pancreas, an organ that sits in our abdomen near our small intestine. Insulin is responsible for regulating our blood sugar levels, as it tells our cells to absorb glucose from the bloodstream so they can use it for energy, or store it for later use.

Insulin resistance occurs when the insulin signaling pathway is disrupted, leading to reduced insulin sensitivity in the body's cells (ie our cells stop responding to insulin the way they should do).

Think of insulin as a key that is needed to turn the lock on our cells in order to let glucose molecules in. Without insulin, our cells cannot use glucose for energy.

To understand this, let’s take a quick look at how insulin works:

After we eat a meal containing carbohydrates, our digestive system breaks down the carbohydrates into smaller sugars, (ie glucose), which can transported into our bloodstream. 

  1. When glucose goes into our bloodstream, our pancreas gets a signal to release insulin. 

  2. Insulin travels through our blood to muscle and fat cells, and binds to receptors on the cell membranes.

  3. When insulin binds to these receptors, this sends a signal that causes GLUT4 (transport proteins) to travel from inside the cell, to the cell membrane (the outer lining of the cell)

  4. Once it reaches the cell membrane, the GLUT4 transporters work like a channel, to allow glucose to get into the cell from the bloodstream. As glucose enters the cells, this causes blood glucose levels to drop back down to a normal range, as all the glucose molecules from the meal are taken up into cells.

  5. Cells can then either store the glucose for later use, or use it to make energy immediately, depending on what they need at that time. Glucose is the main and preferred energy source for our cells.

  6. This means that the main role of insulin is to maintain blood sugar homeostasis, (balance), within our body and bloodstream - ie making sure glucose from food goes to the right place (our cells) and is able to be used. It’s pretty vital!

In insulin resistance, cells in the body, such as muscle, liver, and fat cells, become progressively less sensitive to insulin. As a result, the body must produce more and more insulin to keep blood sugar levels regulated, leading to a condition known as hyperinsulinemia.

Over time insulin levels get higher and higher as cells get more and more resistant to insulin. Eventually, our pancreas may not be able to produce enough insulin to keep up, which then leads to high blood sugar levels and the development of prediabetes and type 2 diabetes.

Insulin resistance is often associated with obesity and a sedentary lifestyle, but it can also be caused by genetic factors, hormonal imbalances, and medical conditions such as polycystic ovary syndrome (PCOS) and non-alcoholic fatty liver disease (NAFLD).

The exact mechanism behind insulin resistance is not fully understood, but research has shown that chronic inflammation may play a role. Inflammation can interfere with insulin signalling pathways, leading to reduced insulin sensitivity. Lipid (fat) accumulation in cells is also thought to contribute to insulin resistance, as excess fat within cells can lead to an accumulation of toxic metabolites, which can interfere with insulin signalling, create inflammation, and reduce insulin sensitivity.

Our bodies are highly efficient at managing energy storage, and any energy we get (from eating food) is either used for immediate energy production or stored as fat for later use.

However, our bodies contain a finite number of adipose (fat) cells, and there is a limit to how much each fat each cell can hold. This means as our cells store more and more fat, they start to reach their storage capacity, causing them to swell up and produce an inflammatory response.

This inflammation downregulates (ie shuts off) the insulin receptors on our cell membrane, telling our cells not to take in any more fat or energy (think of it as trying to stuff more clothing into an overfull suitcase - eventually you have to stop otherwise the suitcase could burst, so the fat cells are trying to protect themselves!).

As cells switch off their insulin receptors, they take in less glucose - so our pancreas has to produce more insulin to try to compensate, and stop our blood sugar levels from rising. But over time, the pancreas can no longer keep blood sugars regulated (as there is nowhere for the glucose molecules to go), and blood sugars rise - causing prediabetes and diabetes.

In simplistic terms, recent research shows that insulin resistance may develop from a continuous surplus of energy in the body (ie eating more calories than our body needs).

This is incredibly common in our modern environment where we are surrounded by high-calorie, highly palatable foods, and spend far less time being active than in previous generations. As a result, insulin resistance and type 2 diabetes rates have skyrocketed over the past few decades, reflecting just how much our environment and diet affect them.



WHAT ARE THE RISK FACTORS FOR INSULIN RESISTANCE

Insulin resistance is complex, and a number of factors can lead to insulin resistance, and increase the risk of developing it.

  1. Genetics: Some people are more prone to developing insulin resistance due to their genetic makeup. This is particularly true in some ethnic groups, such as Maori, Pacific Island, Indian, Latin American, African, and South Asian populations. Genetic variants can affect the way our body processes glucose and insulin, meaning people with these variants are at higher risk of insulin resistance and type 2 diabetes even when they have the same diet and lifestyle as other people.

  2. Excess body weight: Obesity is a major risk factor for insulin resistance, as being overweight or obese can lead to the accumulation of fat in the liver and other tissues, which can interfere with insulin signalling pathways as we’ve just covered. Additionally, obesity can cause chronic low-grade inflammation, which further exacerbates insulin resistance.

  3. Physical inactivity: Lack of exercise and a sedentary lifestyle can contribute to the development of insulin resistance. Regular exercise helps to improve insulin sensitivity, by promoting the uptake of glucose by muscle cells. In contrast, a sedentary lifestyle can lead to decreased insulin sensitivity and an increased risk of developing insulin resistance. Research shows that in healthy people, muscle cells are responsible for using 70-90% of the glucose in our blood. This means if you aren’t moving, your body uses up far less glucose!

  4. Diet: The types of foods we eat can also play a role in the development of insulin resistance. A diet high in processed foods, sugar, and saturated fats can contribute to the development of insulin resistance, as these types of foods can cause inflammation and oxidative stress, interfering with insulin signalling pathways and contributing to insulin resistance.

  5. Sleep disturbances and stress: Lack of sleep has been shown to interfere with glucose metabolism and insulin signalling, causing reduced insulin sensitivity. Sleep apnea is a significant risk factor for insulin resistance, but even chronic sleep deprivation can increase the risk of diabetes. Chronic stress can also lead to increased inflammation and oxidative stress.

  6. Excessive fructose consumption: High intake of fructose (from added sugars, not whole fruit) has been strongly linked to insulin resistance - added fructose is usually found in ultra-processed foods, as well as soft drinks. It can be labelled as fructose, high-fructose corn syrup, honey, agave syrup, invert sugar, maple-flavored syrup, or palm sugar. Out of these, high fructose corn syrup is thought to cause the most health issues.

  7. Altered gut microbiota/dysbiosis: Emerging research looking at the gut microbiome suggests that a disruption in the balance of bacteria in our gut (dysbiosis) can cause inflammation, and lead to the development of insulin resistance. Read more about gut health in our blog post here

  8. Health conditions: such as polycystic ovary syndrome (PCOS), gestational diabetes, high blood pressure, non-alcoholic fatty liver disease (NAFLD), and certain autoimmune conditions such as rheumatoid arthritis and psoriasis can all increase the risk of insulin resistance (as many of these have inflammation as a common underlying cause)

  9. Medications: Steroids, some blood pressure medications, certain HIV treatments and some psychiatric medications can affect blood sugar and insulin levels, leading to insulin resistance over time if used longterm

  10. Hormonal disorders: Cushing’s syndrome, acromegaly, and untreated hypothyroidism (as the thyroid plays an important role in energy and cholesterol metabolism) can all impact on glucose and insulin metabolism, increasing the risk of insulin resistance

WHAT CONDITIONS ARE ASSOCIATED WITH INSULIN RESISTANCE?

Insulin resistance can lead to a range of health problems, including:

  1. Type 2 diabetes: This is the condition most people think of when they hear the words insulin resistance. Insulin resistance is a major risk factor for type 2 diabetes and is what causes pre-diabetes and type 2 diabetes (note type 1 diabetes is NOT related to insulin resistance; it is an autoimmune disease that causes damage to our pancreas and reduces our ability to make insulin). Insulin resistance can actually precede prediabetes by decades and is often not picked up until blood sugar levels are high!

  2. Cardiovascular disease: Insulin resistance is a major risk factor for cardiovascular disease, and significantly increases the chance of having heart attacks or strokes. Chronically high levels of insulin in the blood, in addition to high cholesterol levels, can lead to a buildup of fat in the walls of blood vessels, causing blockages.

  3. Non-alcoholic fatty liver disease (NAFLD): Insulin resistance is a key factor in the development of NAFLD, a condition in which fat accumulates in the liver. Over time, this can lead to liver damage and cirrhosis.

  4. Metabolic syndrome: This is a combination of increased blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol or triglyceride levels. It is a major risk factor for diabetes, heart attacks, and strokes.

  5. Polycystic ovary syndrome (PCOS): PCOS is a common hormonal disorder that affects up to 15% of women in NZ, with higher rates in certain populations (note PCOS often goes undiagnosed so some experts think rates may be much higher). Insulin resistance is a key driver in the development of PCOS, as high levels of insulin are thought to alter hormone secretion in insulin resistant PCOS, which leads to the characteristic symptoms of PCOS (irregular periods, adult acne, excess hair growth or thinning/receding of scalp hair)

  6. Obesity: Insulin resistance is commonly associated with obesity, particularly abdominal or truncal obesity (which can indicate visceral fat - a dangerous buildup of fat around the internal organs). Excess body fat can lead to the release of inflammatory substances that can interfere with insulin signaling pathways, and ironically make it harder to lose weight, even though the excess weight is contributing to insulin resistance in the first place.


HOW CAN I TELL IF I HAVE INSULIN RESISTANCE?

Insulin resistance often develops over years, and often may not cause symptoms in the early stages.

This means prevention is important, in particular trying to follow lifestyle strategies to prevent it if you have any risk factors for insulin resistance.

However, as insulin resistance worsens, several signs and symptoms may start to appear. Some of the common symptoms and signs of insulin resistance include:

  1. High blood sugar levels: Insulin resistance leads to higher levels of glucose in the blood, which can cause symptoms such as frequent urination, increased thirst, and fatigue. This can be detected on a blood sugar test.

  2. Weight gain: Insulin resistance promotes weight gain, especially around the tummy (visceral fat). Insulin promotes the storage of fat in the body, so high levels stimulate additional weight gain (a waist measuring more than 100cm for men and 88cm for women is a warning sign you may have insulin resistance).

  3. Difficulty losing weight: Ironically, people with insulin resistance may also find it difficult to lose weight, even with regular exercise and a healthy diet. We cover this in a bit more detail below.

  4. Dark patches of skin: This is called acanthosis nigricans, and can occur with insulin resistance - particularly in the folds of the skin, such as the neck, armpits, and groin.

  5. High blood pressure: Insulin resistance is often associated with high blood pressure, as similar underlying processes promote both of these. High blood pressure can further increase the risk of heart disease and stroke.

  6. High cholesterol levels: Insulin resistance can lead to high levels of triglycerides and LDL cholesterol, which can increase the risk of heart disease, as well as low levels of HDL (good cholesterol).

  7. Polycystic ovary syndrome (PCOS): Insulin resistance is a common feature of PCOS, and can both contribute to PCOS development, as well as worsen symptoms.

  8. Metabolic syndrome: As mentioned previously, this is a combination of increased blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol levels (high triglycerides and LDL cholesterol, and low HDL cholesterol). It is strongly linked with insulin resistance.



HOW IS INSULIN RESISTANCE DIAGNOSED?

This is tricky, as at present there is no standard validated lab test for insulin resistance

Fasting blood sugar levels and HBA1C tests will detect prediabetes and diabetes, but as insulin resistance can be present for years before these occur, they will only pick it up at a late stage, once the pancreas can no longer produce enough insulin to keep blood sugars under control.

Oral glucose tolerance tests can be helpful, as these measure the bodies response to sugar, but they are time intensive to perform, so are not used routinely. They also check blood sugar response, rather than insulin levels. Similarly, a test called an insulin clamp test is a gold standard test for insulin levels, but is currently only used in research settings.

There are a few indirect measures of insulin resistance that can be done based on fasting insulin and glucose, such as the HOMA-IR test, and the QUICKI test, as well as calculating the ratio of triglyceride to HDL cholesterol, which can all be helpful, but are not currently used as diagnostic criteria.

The triglyceride to HDL ratio is most accessible, as it can be calculated off a normal cholesterol blood test, to calculate it you simply divide your triglyceride reading by your HDL cholesterol reading.

Normal ranges are as follows;

  • In US (mg/dL) – less than 2 is ideal; above 4 is too high

  • In Europe (mmol/L) – less than 0.87 is ideal; above 1.74 is too high 

This can be a helpful indicator to use, alongside signs and risk factors of insulin resistance, to get an idea if you may have it (and should focus on improving it!)

In essence though, as there are no current clear ‘tests’ for insulin resistance, it means it’s important to be on the lookout for the symptoms and signs of insulin resistance mentioned above, and be proactive at taking steps to reduce risk if you have any (or are at high risk of insulin resistance due to other health conditions)!


WHAT CAN I DO TO HELP INSULIN RESISTANCE?

Fortunately, there is a lot you can do!

Insulin resistance is highly responsive to lifestyle changes, meaning small changes can make a big difference.

And given how much insulin resistance can affect the rest of your health, these changes are well worth making (plus they’re great for overall health too!).

Here are our top tips - if this feels overwhelming, just start with one or two things initially that feel most achievable, and try to make these into a regular habit.

Then as you build confidence with these, add a couple more things in. Change is hard, but small sustainable steps are the best way to create change that lasts.

Tip #1: Swap refined carbohydrates for whole grains, and be aware of carbohydrate portion sizes

One of the most effective ways to reverse insulin resistance is to reduce the intake of refined carbohydrates and sugars.

Carbs can be demonized sometimes, yet research shows that whole food plant-based diets (which are naturally high in healthy carbohydrates) can both prevent and reverse insulin and type 2 diabetes - meaning it’s not the carbs that are the issue, but the type of carbs. We have loads of whole food plant based recipes in our Lifestyle Lounge!

Western diets are typically very high in refined carbohydrates (these are grains that have had the fibre and germ removed, ie white flour, white noodles, white rice)

The refining process means these foods are quickly broken down into glucose in the body when we eat them, leading to spikes in blood sugar levels and increased insulin secretion.

In contrast, whole grains and other complex carbohydrates (fruits, legumes, and vegetables) contain fibre and other nutrients which means they are absorbed much more slowly, providing a steady source of glucose when we eat them, rather than a big spike of glucose.

The graphic below shows some simple swaps, we cover carbs, whole grains and more in depth in our Reboot and Nutrition courses if you’d like to learn more.

Being aware of your carb portion sizes is also important - we often eat way more carbs than we need, as they tend to be an easy option - whereas in reality carbs should just be a part of your meal, not the main focus!

Ideally limit carbohydrate-rich foods such as grains and starchy veggies (root veggies) to 25% of your plate, as the graphic below from our courses shows. A serving size for carbs is around 1/2 cup (or 1 slice of bread)


Tip #2: Reduce or avoid added sugars

Sugar can play a massive part in elevating insulin levels, as added sugars (those that are added during the production or cooking process, rather than occuring naturally) tend to cause a rapid rise in glucose levels when we eat or drink them.

This is particularly true for foods high in sugar, that are also low in fibre and protein, such as sweet drinks (including fruit juices!), baking made with refined flour, ultra-processed foods, and many so-called ‘healthy’ foods like commercial cereals, snack foods, and muesli bars.

Whereas when sugar in eaten in whole foods (such as fruit), the fibre in these foods slows down how quickly the sugars are absorbed. This means 2-3 servings of whole fruit/day is ok for most people (and fruit is actually protective against many chronic health issues!).

If you aren’t sure how much-added sugar is in a packaged food, look at the nutrition label.

4g of sugar equates to 1 tsp, and ideally added sugar intake should be limited to a MAXIMUM of 6 tsp/day (24g) for women and 9 tsp/day (36g) for men. Many convenience foods can contain almost a whole days worth of added sugar in just one serving!

Be aware that sugar can be labelled under many different names - this includes typical sweeteners such as cane sugar, raw sugar, brown sugar, maple syrup, honey, agave nectar, as well as highly refined ones such as dextrose and maltodextrin. Ingredients that end in ‘ose’ such as fructose, dextrose, maltose etc are also all sugars.

Reading the ingredients on the label can help give you clues -items on food labels are listed in order from largest to smallest quantity. If one or more of the names for sugar are at the top of the list, that’s a sure sign that the product is high in added sugar!

To learn more about sugar, check out our blog post here. We also have loads of refined sugar free recipes in our Lifestyle Lounge, Reboot course, and Nutrition course.


Tip #3: Increase intake of healthy fats and proteins

We call this putting clothes on your carbs!

Healthy fats and proteins are an important part of a balanced diet, but can also help improve insulin sensitivity, as they help to slow the absorption of glucose into the bloodstream.

Try combining carbohydrate-rich foods such as grains, legumes and starchy veggies with good sources of healthy fats, such as nuts, seeds, avocados, and fatty fish, to create delicious healthy meals that will keep you full without spiking your blood sugar. You can use the healthy plate guide above to guide you.


Protein also helps regulate appetite, as there is a mechanism called the protein leverage hypothesis, which means that we tend to eat until we have consumed enough protein, since it is vital for survival.

In simple terms, this means if we prioritise eating enough protein with meals, we feel full faster, and this helps to avoid overconsuming calories and glucose.

You don’t need to eat huge amounts of protein for this to be effective either - simply aim for around 1/4 of your plate to be protein rich plant foods such as legumes, nuts and seeds (with eggs, lean meats, and fish eaten occasionally if desired), and dial back your carbs and fats.

Research shows that replacing animal protein with plant protein can improve overall health and longevity - so don’t just rely on eggs and meat to get your protein!

We have lots of plant protein rich meal ideas in our Lifestyle Lounge, Reboot Course, and Nutrition course, we also take a deep dive into protein, fat and carbs (and how to eat for better health without restricting) in our courses.

Tip #4: Move your body regularly

Did you know, exercise is one of THE most effective ways to improve insulin sensitivity and reverse insulin resistance?!

During aerobic exercise, our body burns more glucose and fat for fuel, which can help to reduce insulin resistance. Exercise also helps reduce inflammation and improve heart health.

As we mentioned earlier, our muscle cells are what take up 70-90% of the glucose from our blood stream, and the more we exercise, the more glucose we use. Exercise also increases the number of Glut-4 receptors in our muscle cells (those little receptors that insulin attaches to, to let glucose into our cells). This means the more exercise we do, the more effectively our body is able to take up glucose, which improves our insulin sensitivity.

Exercise has the added bonus of building muscle, which also helps increase insulin sensitivity and reduce blood sugar levels. This is because muscle cells are more insulin sensitive than fat cells, ie they can take up glucose without insulin when they are active (ie when exercising), and also need less insulin to take up glucose than other cells. Muscles also burn more energy at rest than fat cells, meaning they keep on working out even when you stop!

Resistance training can also help our body store glucose more efficiently in muscle tissue, further improving insulin sensitivity.

This makes building muscle mass vital for combatting insulin resistance.

Aim for at least 30 minutes of moderate-intensity exercise most days of the week, and don’t forget to include strength training (weights or resistance training).

Ideally aim to do strength training 3 days per week, working all muscle groups in the body.

If you struggle to get a block of exercise in during the day, try exercise snacking - incorporating short bursts of movement throughout the day, as research shows this can be just as effective as one longer workout. Even a 10 minute walk after meals can reduce blood sugar levels by up to 22%!

We cover exercise in depth, as well as lots of practical tips and resources to help you get moving, in our Reboot and Activity courses.

Tip #5: Get enough sleep

Sleep is absolutely vital for overall health, and a good nights sleep can significantly improve insulin sensitivity.

Lack of sleep disrupts our body's circadian rhythms, increasing the production of stress hormones like cortisol. In turn, cortisol can elevate blood sugar and insulin levels, and interfere with insulin sensitivity.

Chronic sleep deprivation is a significant risk factor for type 2 diabetes, and even one night of poor sleep can impact blood sugar and insulin levels!

Aim to get 7-9 hours of quality sleep per night, and consider getting screened for conditions such as sleep apnoea if you are at risk of these, or have typical symptoms (such as persistent snoring, daytime sleepiness, and stopping breathing while sleeping).

To learn more about sleep, how it works, problem-solving for when you aren’t sleeping well, and simple evidence-based tips and resources to improve sleep, in our Reboot and Sleep courses.


Tip #6: Reduce stress

Chronic stress can be a hidden contributer to the development of insulin resistance, as it increases the production of stress hormones such as cortisol, which we’ve just mentioned.

Practising stress-reducing activities like meditation, yoga, or deep breathing can help to reduce stress and improve insulin sensitivity. Learn all about how stress works, how it affects us, symptoms to watch for, and practical ways to reduce stress (and improve stress resilience) in our Reboot and Stress courses

Tip #7: Consider fasting

Intermittent fasting or time-restricted eating can be effective in reversing insulin resistance, although caution is needed if you have a history of eating disorders, are underweight, are on prescription medications, have health issues that affect the absorption of nutrients or food, or are pregnant/breastfeeding.

It is important to talk to your doctor in this situation before considering any form of fasting.

Fasting can bring down insulin levels and promote the breakdown of fat stores for energy, as well as potentially help to improve blood sugar control and reducing the risk of insulin resistance.

There is ongoing research looking into various forms of fasting such as circadian eating, time-restricted eating, fasting-mimicking diets, and intermittent calorie restriction, with fairly promising results.

Time-restricted eating (not eating for a 12-16h window overnight) is often the safest and easiest form of fasting to start with, as it simply involves not eating after dinner and delaying breakfast slightly, and can be highly effective in improving blood sugar levels.

But as always, it is important to listen to your body though, as fasting does not suit everyone!

We take a deep dive into the pros and cons of fasting, types of fasting, and how to do it safely, in our Reboot and Nutrition courses.

Tip #8: Supplements

As always, we recommend taking a lifestyle-first approach for improving insulin resistance, as this has the most evidence to back it up, and is also the safest!

From a supplement perspective though, there is some research to suggest the following may help improve insulin sensitivity and blood sugar levels (although for most of them trials are small meaning the quality of the evidence is low):

  1. Magnesium - trials show magnesium at a dose of approximately 300-400mg/day can improve fasting blood sugar levels (but not HbA1C) and can also help cholesterol levels and blood pressure. Many Western diets are low in magnesium - rich food sources including whole grains, leafy green vegetables, legumes, and nuts.

  2. Alpha Lipoic Acid (ALA) - one small trial showed significant improvements in fasting and post-meal blood sugar levels taking 300 mg daily for 8 weeks. ALA is an antioxidant made by the body, and found in small amounts in food.

  3. Vitamin D - large population studies have long shown a link between vit D deficiency and a higher risk of diabetes, with more recent data showing that people with the higher vitamin D levels have a 43% lower risk of developing type 2 diabetes mellitus (T2DM) compared with those who have the lowest levels. Supplementing Vit D to aim for the higher end of normal ranges can help improve blood sugar control in diabetics, improve insulin sensitivity, and improve blood pressure, cholesterol, and inflammatory markers. One large meta-analysis from this year, showed that vitamin D supplementation could help prevent people with prediabetes from developing diabetes by 15%, while people in the trial who maintained their vit D levels at the high end of normal at 125 nmol/L (≥50 ng/mL) compared with 50 to 74 nmol/L (20 to 29 ng/mL), had an even greater reduced risk for diabetes of 76%. The normal reference ranges for vit D in NZ are 50-150nmol/L. Vit D also increased the likelihood of reversing prediabetes by 30%. Doses used in this trial were 4000iu/day, note vit D is toxic in overdose so blood test monitoring is usually recommended (prescription vit D is a monthly dose of 50,000IU, which works out to 1666IU/day)

  4. Folate - this is a B vitamin, which may help lower blood sugar levels and improve insulin sensitivity. Folate supplementation is used to reduce homocysteine levels, an inflammatory marker associated with higher rates of diabetes, insulin resistance and also heart disease and strokes. Trials on folate supplementation show it can help reduce fasting blood sugar levels, but not HBA1C levels. Folate is found in dark green leafy veggies, brassica, and legumes, so plant-focused whole food diets generally contain lots of it!

  5. Fibre - fibre in foods helps to lower blood sugar levels, by slowing absorption of glucose. Diets high in fibre also protect against diabetes and can help improve blood sugar control in diabetics. From a supplement perspective, psyllium husk has been shown to improve blood sugar levels, fasting blood sugar, and HBA1C, it is also great for gut health.

  6. Apple cider vinegar - some research shows that taking 1=2 tbsp apple cider vinegar with a meal can help reduce blood sugar levels. It appears to help delay stomach emptying (slowing glucose absorption), reduce blood sugar, and improve insulin sensitivity. One study found that consuming apple cider vinegar increased insulin sensitivity by 34% during a high-carb meal in people who were insulin resistant and by 19% in people with type 2 diabetes.


WRAPPING IT UP

We hope you’ve enjoyed this post on insulin resistance, and have learnt some useful tips to apply to your own life! Being diagnosed with insulin resistance, prediabetes, or diabetes can come as a shock, yet there are also so many simple, evidence-based changes you can make, that will have a massive impact - both on your health and also on how well you feel!

If you need some more personalised help with your health, we offer in-person consultations in Nelson and Wanaka, as well as secure telemedicine consultations NZ wide. Find out more here

Or to take a deeper dive into how to transform your health, check out our Reboot course, or Focus courses.

You can also try our Lifestyle Lounge for $1, and our blogs and podcast episodes are completely free to access.

Whatever your need is, we look forward to helping you on your journey to better health, today ❤️


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Diabetes Superstar Foods | ADA

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