Other blogs on this website that discuss insulin insensitivity:

Berberine & Insulin Sensitivity

Insulin Sensitivity and Menopause, The Evidence

Africa, Insulin Sensitivity & Meal Timing

 

If you feel like you’ve tried everything to lose weight and your body just won’t budge, this is a must-read ↓

Alright, let’s break down what insulin is, what it does in our bodies, what insulin insensitivity means, and what we can do about it.

What is Insulin?

Imagine insulin as a little key. Its main job? To unlock your body’s cells so that sugar (glucose) from the food you eat can enter and be converted into energy. Whenever you eat, your blood sugar levels rise. This rise signals your pancreas (a slim organ behind your stomach) to release insulin, which helps remove the sugar from your bloodstream and deliver it to the cells of your body for use as energy when needed.

What Does Insulin Do?

Basically, insulin keeps your body’s sugar levels in check, preventing them from getting too high or too low. Think of it as the body’s natural blood sugar manager. When everything’s working right, it helps your body store the extra sugar for when you need energy between meals.  This is a good thing. We want that sugar available to convert into usable energy when we need it to crush our workouts or get through busy days.

What is Insulin Insensitivity?

Now, onto insulin insensitivity, also known as insulin resistance. This happens when your body’s cells start giving the cold shoulder to insulin — they just don’t respond to that “key” like they used to. When insulin isn’t allowed to do its job (because the cells aren’t responding properly), the glucose (sugar) builds up in your blood instead of going into the cells for energy.

So what happens to all that excess sugar? Well, it doesn’t just vanish; your body has a plan B: converting and storing it as fat.  The liver and muscles store some of that glucose as glycogen, but there’s a limit to how much they can hold. Once those storage areas are full, the body starts turning the glucose into fat that is stored on your body. Even worse, that extra sugar in the blood over time may even lead to type 2 diabetes.

There’s more. In response to high blood sugar levels and the inefficiency of the initial insulin response, the pancreas produces and releases more insulin to try to get cells to respond and to manage the excess sugar. This compensatory mechanism can maintain normal blood sugar levels for awhile.  But eventually…

Problems with High Insulin Levels

While this extra insulin might help initially manage blood sugar levels, having high insulin levels (hyperinsulinemia) circulating in the body over time can lead to several health issues:

Enhanced Fat Storage:

Insulin is not only a blood sugar regulator but also a fat storage hormone. Higher insulin levels promote the storage of fat, particularly in the abdominal area. This can lead to weight gain and obesity, further exacerbating insulin resistance.

Cardiovascular Disease Risk:

High insulin levels are associated with an increased risk of cardiovascular diseases. Insulin promotes the synthesis of cholesterol and can lead to arterial wall thickening, contributing to hypertension and atherosclerosis.

Hormonal Imbalances:

Excess insulin can affect other hormonal pathways. For example, in women, it can lead to increased androgen production, which can disrupt normal menstrual cycles and cause symptoms like acne, hair growth, and ovulatory dysfunction, seen in conditions like polycystic ovary syndrome (PCOS).

Increased Risk of Type 2 Diabetes:

Over time, the pancreas’ ability to produce sufficient insulin to overcome cell resistance can diminish, leading to the development of type 2 diabetes.

Contributing to Inflammation:

Chronic high insulin levels can lead to a state of low-grade systemic inflammation, which itself can perpetuate insulin resistance and contribute to the development of chronic diseases.

Risk of Non-Alcoholic Fatty Liver Disease (NAFLD):

High insulin levels can lead to fat buildup in the liver, which may progress to NAFLD, a major cause of liver disease worldwide.

 

The Cycle of Weight Gain

Here’s where it gets even more intertwined. Fat cells aren’t just inert storage units; they actively release hormones and substances that can further increase insulin resistance (that’s why being overweight in itself a contributor to being insulin resistant). This means even more sugar stays in the bloodstream, prompting more fat storage—a vicious cycle that can be tough to break.

What Contributes to Insulin Insensitivity?

Being Overweight

Fat cells release free fatty acids into the bloodstream that can interfere with insulin signalling pathways, thereby reducing insulin sensitivity in muscle and liver cells.  Fat cells also produce several types of cytokines called adipokines.  Tumor Necrosis Factor-alpha (TNF-α) is a pro-inflammatory cytokine that can impair insulin signaling and Interleukin-6 (IL-6) that, when elevated, can contribute to systemic inflammation and insulin resistance.

Lastly, Retinol-Binding Protein 4 (RBP4) is a protein secreted by fat cells that can decrease insulin sensitivity in muscles and increase glucose production by the liver.

Lack of Exercise

Exercise improves the insulin signaling pathway itself. When you regularly engage in physical activity, the cells in your muscles become more responsive to insulin.

During exercise, your muscles require more glucose to meet the increased energy demand. To facilitate this, exercise stimulates the translocation of GLUT4 receptors to the surface of muscle cells. These receptors help pull glucose out of the bloodstream and into the muscle cells without the need for insulin, thus lowering blood glucose levels and increasing insulin sensitivity.

Exercise helps you reduce body fat and build more muscle mass, both of which improves insulin sensitivity. With more muscle mass, your body has a greater capacity to store glucose, reducing the amount circulating in the blood and thus lessening the burden on the insulin-producing cells in the pancreas.

Lastly, exercise stimulates the release of various hormones that can positively affect insulin sensitivity. For example, exercise-induced increases in growth hormone and testosterone levels can contribute to better muscle growth and fat distribution, impacting insulin sensitivity positively.

Poor Diet, Particularly One High in Sugar

Of course, eating a lot of sugar means your body has to produce a lot of insulin to tackle it – which contributes to insulin insensitivity.

Age

Sadly like many things, our insulin doesn’t work as well in our bodies as we age. This process is multifaceted and involves changes in body composition, hormones, and cellular function that occur as we get older.  We can offset these changes by staying as active and as lean as we can, and of course, maintaining a healthy diet.

Menopause

Unfortunately, estrogen isn’t just about reproductive health; it also plays a role in how your body uses insulin. It is well documented that when women’s estrogen levels plummet during and after menopause, insulin works less effectively in the body. Read more about this here.

 

Sleep

While you’re snoozing, your body isn’t just lying there; it’s busy repairing cells, balancing hormones, and resetting stress levels. Here’s the science bit:

HORMONE REGULATION: 

During deep sleep, your body regulates hormones like cortisol (the stress hormone) and growth hormones. These hormones are crucial because they help manage insulin sensitivity. If you don’t get enough sleep, cortisol levels stay higher than they should.  High cortisol can lead to higher blood sugar levels and therefore eventually also to insulin resistance. This happens because cortisol can make your cells less responsive to insulin.

FAT STORAGE & APPETITE:

Lack of sleep can mess with other hormones too, like leptin and ghrelin, which control feelings of hunger and fullness. When you’re sleep-deprived, ghrelin goes up (hello, hunger!), and leptin goes down (you don’t feel as satisfied after eating). This can lead you to eat more, often choosing higher sugar and fatty foods, which can further exacerbate insulin resistance.

Stress

When you’re stressed, whether a physical or emotional stress, your body thinks it’s under attack and switches to ‘fight or flight’ mode – which does a couple things:

INCREASED GLUCOSE PRODUCTION:

Your body releases extra energy (glucose/sugar) to prepare for the ‘fight.’ But without the physical release (because you’re not actually fighting or fleeing), this glucose piles up in the blood. Chronically higher glucose means more insulin needs to be produced to clear it.

CORTISOL & ADRENALINE SURGE:  

Stress hormones like cortisol and adrenaline kick in. These increase your blood sugar by making your liver produce more glucose and by making cells more resistant to insulin, as part of the body’s natural response to stress.

FAT STORAGE: 

Cortisol doesn’t just spike your blood sugar.  Like excess blood sugar itself, cortisol also helps store fat, particularly around the belly. And more fat, especially around this area, can lead to—you guessed it—greater insulin resistance.  Another vicious cycle.

 

Symptoms of Insulin Insensitivity

Insulin insensitivity, or insulin resistance, exists on a spectrum with varying degrees of severity that can affect individuals differently. Understanding this spectrum and recognizing early symptoms can help manage and possibly mitigate the progression toward more serious health conditions.

The Spectrum of Insulin Insensitivity

Mild Insulin Resistance:

In the early stages, insulin insensitivity might not be very pronounced and can often go undetected in routine medical exams. At this point, the pancreas compensates for the reduced efficiency of insulin by producing more of it. Blood glucose levels might still appear normal because of this compensatory increase in insulin production.

Moderate Insulin Resistance:

As resistance increases, the signs become more noticeable. The pancreas struggles to keep up, and blood glucose levels may begin to rise above normal levels, particularly after meals. This stage may lead to prediabetes, where blood sugar levels are higher than normal but not yet high enough to be classified as diabetes.

Severe Insulin Resistance:

At this advanced stage, the pancreas can no longer produce enough insulin to overcome the body’s resistance, leading to type 2 diabetes. At this point, insulin resistance is often accompanied by other health issues like high blood pressure, high cholesterol, and significant weight gain, especially around the waist.

Early Symptoms and Impact Before Diagnosis

INCREASED HUNGER: 

Insulin is a key regulator of hunger signals. When your body’s cells aren’t absorbing glucose effectively, it can lead to an increase in hunger, even after eating, as the cells aren’t receiving the energy they need.

FATIGUE:

Without adequate glucose entering your cells, your body lacks the energy to function optimally, leading to feelings of fatigue and tiredness.

WEIGHT GAIN:  

Particularly around the abdomen. Insulin promotes fat storage, especially when it is abundant, and the cells are not using glucose efficiently, leading to increased fat storage around the waist.

BRAIN FOG: 

Insufficient glucose supply to the brain can affect cognitive functions, resulting in difficulty concentrating, memory lapses, and a general sense of mental fog.

DARKENING OF THE SKIN (ACANTHOSIS NIGRICANS):

In some cases, more advanced insulin resistance can cause changes in the skin, particularly in the neck and armpits, where it becomes darker and thicker.

 

Preventing or Breaking the Cycle

Knowing all this, how can you keep life from pushing you towards insulin resistance? Here are a few science-backed tips:

• Prioritize good sleep hygiene

• Manage stress actively

• Regular physical activity & lift weights

• Maintain a low to no sugar diet

• Maintain a healthy body fat percentage

Other nutritional strategies:

There’s lots of other nutritional strategies that can help improve insulin sensitivity, beyond just avoiding refined sugars.

1. Increase Fibre Intake

High-fibre foods slow down digestion. This leads to a more gradual increase in blood sugar levels rather than spikes, which also reduces the amount of insulin that your pancreas has to produce.  We have entire collection of high-fibre recipes available in the vast library as part of our nutrition membership, RxHABITS. Foods high in fibre include:

• Whole grains like oats, barley, and quinoa
• Legumes such as beans, lentils, and chickpeas
• Vegetables and fruits

2. Choose Low-Glycemic Index Foods

Foods with a low glycemic index (GI) raise blood sugar levels more slowly than high-GI foods – again, thereby reducing the amount of insulin that must be secreted. Incorporating more low-GI foods can help manage blood glucose levels and enhance insulin sensitivity. Examples of low-GI foods include:

• Non-starchy vegetables
• Most fruits
• Whole grains
• Nuts and seeds

3. Incorporate Healthy Fats

Monounsaturated and polyunsaturated fats can help improve insulin sensitivity. These fats are found in:

• Olive oil, avocado, and other vegetable oils
• Nuts and seeds
• Fatty fish like salmon, mackerel, and sardines, which are high in omega-3 fatty acids

4. Increase Protein Intake

Eating enough protein daily, and specifically having some when you eat all meals and snacks can help slow digestion of any carbs and therefore stabilize blood sugar levels.  Furthermore adequate protein intake supports muscle mass, which is beneficial for insulin sensitivity and metabolic health. Choose lean protein sources such as:

• Chicken or turkey breast
• Fish
• Legumes
• Tofu and other soy products

5. Regular Meal Timing

Eating meals and snacks at regular times each day can help maintain stable blood sugar levels and improve insulin sensitivity. Avoid skipping meals, which can lead to significant fluctuations in blood sugar levels. Some people do very well with smaller more frequent meals and snacks throughout the day. However, often omitting snacks entirely and eating less often in a day can also be helpful – as was the case for me.

6. Limit Saturated and Trans Fats

Reducing intake of saturated fats and trans fats is crucial for enhancing insulin sensitivity. These fats can contribute to inflammation and worsen insulin resistance. Limit foods such as:

• Processed snacks and baked goods
• Fried foods
• High-fat dairy products
• Fatty cuts of meat

7. Stay Hydrated

Proper hydration is important for maintaining metabolic health. Water does not directly improve insulin sensitivity, but dehydration can negatively affect blood sugar levels and insulin response.

8. Consider Anti-Inflammatory Foods

Chronic inflammation plays a critical role in the development and progression of insulin insensitivity. It involves the activation and release of various pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β). These cytokines can interfere directly with insulin signaling pathways. Also, adipose tissue (fat) secretes more pro-inflammatory cytokines and fewer anti-inflammatory cytokines like adiponectin, which also impact insulin sensitivity.  Anti-inflammatory compounds exist mostly in whole foods, particularly:

• Spices like turmeric and cinnamon
• Leafy greens
• Blueberries and cherries
• Fatty fish

9. Monitor Alcohol Intake

Excessive alcohol consumption is shown to have negative effects on blood sugar regulation and insulin sensitivity. Although some studies suggest that a small amount temporarily may improve insulin sensitivity.  Moderation is key here.

10. Supplements That May Help

Several supplements have been studied for their potential to improve insulin sensitivity:

• chromium
• ALA
• berberine
• resveratrol

Particularly berberine – a compound found in several plants like Goldenseal, Barberry, and Oregon grape – is gaining recognition for its potential to manage blood sugar levels and reduce sugar cravings. It’s been shown to enhance insulin sensitivity by activating an enzyme called AMP-activated protein kinase (AMPK), often referred to as a “metabolic master switch.” By improving how effectively your body uses insulin, berberine helps regulate blood sugar levels, reducing the rapid spikes and drops that can trigger sugar cravings. Research, including a study published in the “Metabolism” journal, highlights berberine’s role in improving insulin action and reducing insulin resistance, which is crucial for maintaining stable blood sugar levels.  Read more here.

It’s important to note that while these supplements can help manage insulin resistance, they should be used as part of a larger comprehensive approach that includes diet, exercise, and lifestyle changes.  You should always consult a healthcare provided before starting any new supplement, especially if you have underlying health conditions or are taking other medications.

 

IN SUMMARY…

If you suspect your insulin isn’t working as well as it used to, talk to your physician about it.  Ask them to check both your fasting glucose and fasting insulin levels.  If you’d like to pick my brain and explore strategies together to tackle your weight gain and possible insulin insensitivity, reach out today!

 

 

 

 

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