Is Insulin Resistance to Blame for Weight Gain?

Is there ever a time when you feel you just can’t lose weight no matter what you do? Or have you noticed that you gain weight easily, even with a healthy diet and regular exercise? If so, you may be experiencing insulin resistance, which results in chronically high insulin levels in the blood due to a decreased response to insulin.

We’re going to discuss insulin resistance, how it contributes to weight gain, and how it can be addressed.  

What is insulin, and How does it work?

A hormone called insulin helps your body regulate blood sugar levels. The body converts carbohydrates into glucose, which enters your bloodstream. Afterward, your cells take up glucose for energy or store it for later use as insulin signals them. 

What is insulin resistance?

Insulin resistance is a condition whereby the body’s cells become insensitive to insulin, leading to chronically high insulin levels in the blood. This can result in various metabolic abnormalities, including impaired glucose tolerance, dyslipidemia, hypertension, and an increased heart disease and diabetes risk.

Several factors can contribute to insulin resistance, including genetics, Obesity, physical inactivity, poor sleep, and certain medications. Additionally, processed carbohydrates, sugar, and fats impair insulin sensitivity and increase resistance.

Normal Insulin Levels

Understanding normal insulin levels is essential to determine whether or not you have insulin resistance. A person’s insulin levels vary according to whether or not they have eaten recently.

Fasting insulin levels:

Fasting insulin levels are used to assess insulin resistance and sensitivity after an overnight fast. According to the American Diabetes Association (ADA), normal fasting insulin levels are the following:

•  Adults should have less than 25 micro IU/mL (mIU/L) 
• Children and adolescents should have less than 20 mIU/L 

In other sources, however, it is recommended that levels below 10 mIU/L be maintained.

Here’s the thing, having a fasting insulin level between 10-25 mIU/L) may make weight loss difficult.  If you’ve followed me long enough you know I’m all about optimization.  Just because the standard reference range shows you’re normal doesn’t mean it’s your normal.  

To me this is the art of healthcare.  Although mass populations may not need to maintain levels below 10, it’s likely that a subset of people need more optimal levels. 

Optimal insulin levels:

To date there is no scientific consensus on optimal insulin levels.  But if you think upstream, for some, optimization may be required.  This is where genetics may be at play. In fact, having certain combinations of glucose and insulin regulating genetic SNPs can make optimization necessary for you to maintain a healthy weight and avoid disease. 

For example, glucose and insulin balance begin at the genetic level.  There are seven genetic glucose & insulin influencers…

• pancreatic dysfunction
• pro-inflammatory fat & inflammation
• glucose & triglyceride clearance from the blood
• obesity
• sedentary lifestyle
• skeletal muscle
• liver

Combinations of certain genes in each of these determine where your insulin may normally hang out.  Requiring a different approach just to bring your blood glucose and insulin level to acceptable ranges that will prevent issues with weight gain. 

Additionally, we know a fasting insulin can detect early signs of insulin resistance.  So regular monitoring is useful for catching dysregulation in your metabolic markers. 

In fact, research shows that a fasting insulin greater than 7 as being associated with a significant increase in future risk metabolic syndrome and type 2 diabetes.  So some may have better health outcomes by tightening up their reference range to 2-5 mIU/L.

This is where working with a practitioner like myself can be helpful as some individuals need optimization of metabolic markers to get desired results. 

Weight Gain and Insulin Resistance

High insulin levels, such as those associated with insulin resistance, signal the body to store glucose instead of burning fat for energy. This is because insulin promotes glycogen uptake and storage by cells, particularly fat cells while inhibiting fat breakdown and use by muscles and other tissues. As a result, fat cells store glucose as fat.  Further compounding weight gain. 

Additionally, high insulin levels can promote fat storage and insulin resistance, as they can make cells desensitized to insulin over time. In response to the reduced response of the cells, the body produced even more insulin, resulting in higher insulin levels and worsened insulin resistance. Moreover, high insulin levels can contribute to weight gain by increasing hunger and cravings for carbohydrate-rich foods. This is because insulin stimulates the production of neurotransmitters that regulate appetite and mood. 

Studies link insulin resistance to weight gain

There have been several studies showing that insulin promotes fat storage. The journal Obesity published a study in which healthy volunteers burned less fat and more carbohydrates as energy when their insulin levels were raised, indicating the body preferred glucose over fat as a fuel source. 

Another study found that high insulin levels reduced fat availability for energy by inhibiting the release of fatty acids from fat cells. Therefore, maintaining normal insulin levels is crucial to promoting fat metabolism and preventing fat storage. This can be achieved through healthy eating, regular exercise, and maintaining a healthy weight.

Diet and Insulin Resistance

Is there a specific “diet” one should follow with or to prevent it?  Again, this is all very individual.  As some may require a tight regulated low-carb diet, where others will benefit from including more carbohydrates.  This is why personalization is beneficial, and why I find genetic testing so helpful.  Just saying everyone with insulin resistance has to follow a very low-carb or ketogenic diet is misleading.  And unnecessary. 

However, most practitioners would agree that to improve insulin levels will require consuming fewer carbs. Therefore it’s crucial to understand which diets that may contribute to promoting or preventing insulin resistance.

In fact, studies show there are foods that can play a big role in preventing and resolving insulin resistance:

• Plant-based foods

One study suggests that a diet high in protein without adequate plant-based foods may contribute to insulin resistance. Although an animal study, the research found that mice fed a 90% animal protein and 10% plant protein diet had higher insulin resistance than mice fed a 50% animal protein and 50% plant protein diet. 

According to the study, insulin resistance may be associated with excessive animal protein intake without adequate intake of plant-based foods. The study highlighted the importance of a balanced diet with plant-based nutrition to prevent insulin resistance. 

Now let’s have a conversation about the bariatric high protein low-carb diet most follow.  Although I do believe many will have better success following this style of eating, I don’t think it has to be a very low-carb diet.  You see, bariatric patients are at risk for insulin resistance due to their higher risk of Obesity and related conditions. 

After bariatric surgery, many patients prioritize protein intake and do not consume enough plant-based foods. Many are notorious for filling up on  a lot of meat and cheese. Not having adequate belly space for plants.  Additionally, you have to factor in the ease of drinking protein shakes, bars, and chips, which are lacking fiber and other nutrients. Yet allowing you to hit your protein goals. 

• Mediterranean or low-carb diet

Mediterranean and low-carb diets are effective in reversing insulin resistance in several studies. 

A study found that a Mediterranean diet low in carbs and high in fat improved insulin sensitivity and reduced inflammation markers in obese adults.

Similarly, another study published in the Journal of Clinical Endocrinology and Metabolism found that people with type 2 diabetes who ate a low-carb diet had improved insulin sensitivity and glucose control. Diets containing 14% carbs, 28% protein, and 58% fat led to significant improvements in HbA1c levels, a long-term blood sugar marker.

Researchers suggest that switching to a low-carb or Mediterranean diet may benefit people with insulin resistance. Again, more evidence for personalization. However, dietary requirements vary from person to person, so before making any significant dietary changes, consult a healthcare professional like myself for guidance. 

• Prebiotic and Fiber

Studies have shown that consuming prebiotic fibers, overall fiber, and probiotics can reduce insulin resistance. Prebiotic fiber is a non-digestible fiber that helps promote the growth of beneficial bacteria, thus improving insulin sensitivity. Several prebiotic fibers have been found to reduce insulin resistance and improve insulin sensitivity, including inulin and fructooligosaccharides.

Further, studies have shown that adequate fiber intake helps control blood sugar levels and insulin sensitivity. Evidence shows that higher fiber intake reduces the risk of type 2 diabetes and improves glycemic control. Additionally, probiotics, which are live bacteria that confer health benefits, have been linked to improved insulin sensitivity and glucose metabolism.

Hence, consuming foods rich in prebiotic fiber, fiber, and probiotics support metabolic health and reduce.

Uric Acid and Insulin Resistance

A study suggests that uric acid may contribute to insulin resistance as well. The kidneys normally excrete uric acid, but inflammation and it can result if levels are high. Maintaining a healthy diet, avoiding foods high in purine, and limiting alcohol consumption will help you reduce uric acid levels.

Lifestyle Factors and Insulin Resistance

Finally, lifestyle factors like poor sleep, lack of exercise, and menopause can also contribute to and weight gain. Here’s a brief overview of how each of these factors influences insulin resistance:

• Poor Sleep: 

Studies have shown that people with poor sleep have increased insulin resistance, glucose intolerance, and an increased risk of type 2 diabetes. Research suggests that short sleep duration, poor sleep quality, and sleep-disordered breathing affect glucose metabolism and hormone regulation, contributing to insulin resistance.

• Exercise: 

Exercise and physical activity have numerous health benefits, including improved insulin sensitivity, lower blood glucose levels, and improved metabolic health. 

It increases glucose transporter type 4 (GLUT4) expression in skeletal muscles, which increases insulin sensitivity.

• Time-Restricted Feeding(TRF): 

TRF, also known as intermittent fasting, has become famous for improving insulin resistance and metabolic health. Studies have shown that TRF can help reduce inflammation, increase insulin sensitivity, and promote weight loss, especially when combined with an exercise program that promotes weight loss.

• Menopause: 

Menopause is important for women’s health since hormonal changes during menopause can increase insulin resistance and the risk of metabolic disorders like type 2 diabetes. In menopause, women should maintain a healthy weight, exercise regularly, and eat fiber-rich and plant-based foods.

In general, lifestyle factors such as exercise, sleep, and diet are essential in improving insulin resistance. Hence, if you want to manage, a holistic approach incorporating your lifestyle, dietary habits, and medical history is imperative.

Conclusion

A person with insulin resistance may gain weight and have difficulty losing weight. Therefore, preventing and resolving insulin resistance can aid in improving insulin sensitivity while achieving a healthy weight. You can control and lose weight by eating a balanced diet, consuming adequate fiber, reducing uric acid, and maintaining a healthy lifestyle.