How to Improve Insulin Sensitivity

According to Dr. Michael Goran, PhD and Professor of Pediatrics at Children’s Hospital of Los Angeles, the average American consumes 150 pounds of sugar per year. That is more than a 36,000% increase in the past 250 years.¹ In 2018, The American Diabetes Association published data showing over 10% of the U.S. population met the criteria for some form of diabetes.

These numbers should tell us to pause and evaluate our sugar consumption. While this article itself is not directly about diabetes, we will cover some of the key principles of diabetes, such as sugar, insulin, insulin sensitivity, and how to increase insulin sensitivity

What Is Insulin?

Insulin is a peptide hormone created and secreted by beta cells within the pancreas. When we eat sugar, insulin is released to facilitate metabolism by binding directly to receptors on the outside of cells. Insulin receptors are present on all cells within the body, with fat cells (adipocytes) and liver cells (hepatocytes) having the highest amount. When insulin binds, it allows the cell to transport sugar (glucose) inside—this process lowers blood sugar levels. Without insulin, our cells cannot absorb or utilize sugar as an energy molecule. ³

Insulin has many natural, important functions: ^2,3,4,8

• In liver cells, insulin facilitates a process called glycogenesis. This means the cell takes sugar and turns it into glycogen, so it can be stored and used later.
• In fat cells, insulin promotes storing sugar as fat.
• In muscle cells, insulin promotes protein synthesis and glycogenesis.
• In pancreas cells, insulin regulates the secretion of glucagon, which is a hormone that facilitates cells releasing stored sugar into the bloodstream. Insulin and glucagon are hormones that regulate each other.
• In brain cells, insulin is involved in appetite regulation.

In summary, insulin regulates the metabolism of carbohydrates, protein, and fat for every cell within the body.

<p class="pro-tip">Learn more about<a href="/blog/insulin-and-weight"> how excess insulin leads to weight gain</a></p>

What Is Insulin Sensitivity?

Insulin sensitivity, commonly known as insulin resistance, is defined as impaired insulin signaling. Essentially, this term attempts to measure how well the body responds to insulin and sugar levels. This involves the complex interplay of many metabolic pathways, including:⁸

• Fat (lipid) metabolites and the creation of fat (lipogenesis).
• Protein (amino acid) metabolites and synthesis.
• Emerging evidence shows increasing links to the gut microbiome.

Standard of care involves measuring your blood sugar level and a lab called an A1c. Studies are currently underway to evaluate if measuring other biomarkers, such as adiponectin, RBP4, chemerin, A-FABP, FGF21, fetuin-A, myostatin, IL-6, irisin, and the gut microbiome can be useful labs to follow in the future. ¹¹

If insulin plays such critical roles in all bodily functions and metabolism, then what causes insulin insensitivity?

Sugar causes certain neurons in the brain to release natural opioids and dopamine, thus triggering the same pleasure center circuitry that is activated by drugs and alcohol. One study demonstrated that fructose and alcohol follow a similar metabolism pathway in the liver, cause similar types of liver inflammation (fatty liver), both cause increased visceral fat tissue, and activate the same hedonic pleasure pathway in the brain.^5,6 Fructose tastes much sweeter than regular glucose (sugar), and has been found to stimulate parts of the brain that override the switch that causes the brain to feel full.⁷

While food and sugar themselves do not meet criteria as an addiction (this is a heavily debated topic), our bodies are genetically designed to crave sugar and store this for future use. When humans would regularly experience extended times of fasting, and even starvation, we adapted by storing fat and glycogen for future use. This process of gaining and losing weight, from an evolutionary perspective, promoted our survival as a natural compensatory mechanism. 

As well defined by Dr. Goran, one of the leading experts on sugar, as we consume dangerously high amounts of sugar and sugar substitutes, our pancreas and hormones simply cannot compensate.¹ The pancreas works hard to produce high amounts of insulin to combat sugar-saturated diets. Over time, the cells in our body grow less and less sensitive to insulin, further pressuring the pancreas. This triggers a vicious cycle that can fatigue the beta cells within the pancreas entirely, causing our bodies to stop producing insulin altogether. This process is evaluated by measuring insulin sensitivity. ⁸

<p class="pro-tip">Learn more about<a href="/blog/insulin-resistance-vs-prediabetes"> insulin resistance vs. prediabetes</a></p>

How Do I Increase My Insulin Sensitivity?

1. Reduce or eliminate eating saturated fatty acids (SFAs).

SFAs disrupt healthy insulin signaling by activating pro-inflammatory molecules.⁸ They include foods like cakes, pastries, pies, butter, lard, and fatty processed meats such as sausage. Reach instead for vegetables, olive oil, and lean meats like chicken and turkey.

^{2. Animal studies suggest improved insulin sensitivity when eating polyunsaturated fatty acids (long-chain omega-3 fatty acids such as EPA and DHA).}8

While studies in humans are still a bit controversial, increasing your omega-3 fatty acids can help. These include fish such as mackerel, salmon, chia seeds, walnuts, and seabass. They can also be taken in pill form as a supplement (I personally take 850 mg of EPA and 200 mg of DHA every day).

3. Consume monounsaturated fatty acids (MUFAs).

Foods rich in MUFAs are things like plant-based oils such as avocado, oil, and peanut oils. Intake of MUFAs is associated with improved insulin sensitivity.⁹ 

^{4. Eliminate artificial and processed sugars.}  

Albeit marketed as a healthy alternative to sugar, fructose and artificial sweeteners are directly related to metabolic syndrome, obesity, and insulin resistance. They disrupt our healthy gut microbiome, lead to decreased satiety (feeling full), cause us to eat more, and alter how sugar is metabolized.^{10, 19}

Animal studies showed that feeding rodents a high-fat sucrose diet resulted in insulin resistance, high triglycerides, enhanced blood clotting, high blood pressure, and metabolic syndrome after just a few weeks!

The first two weeks are arguably the hardest as you battle sugar cravings, but after going so long without eating processed sugar, you’ll notice how sick you feel when you eat them again. Completely remove things like aspartame and high fructose corn syrup commonly added to diet sodas, gum, and candy. Reach for bubbly water flavored with a real lime or lemon instead. 

<p class="pro-tip">Learn more about<a href="/blog/insulin-resistance-diet"> the insulin resistance diet</a></p>

5. Exercise!

Extensive studies show that both light continuous and high-intensity interval training improve insulin sensitivity, decrease fat tissue, and naturally treat metabolic syndrome.^{12, 16} Try for 30 minutes of exercise four to five times a week. This can be as simple as going for a 1 mile walk every evening. For those who struggle with chronic pain or mobility issues, swimming and recumbent cycling can be excellent, low-impact forms of exercise.

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6. Reduce chronic levels of inflammation and stress.

Reducing chronic inflammation and stress is important for optimal health outcomes. Learn how inflammation and stress affect your body long term and how to combat this.

7. Practice sleep hygiene by protecting your natural sleep circadian rhythms.

Studies show that those with shift work sleep disorder and circadian misalignment have worse signs of glucose control.¹⁴ Not getting adequate, restful sleep puts stress on the mind, body, and lowers insulin sensitivity.

8. Be mindful of your sugar intake, even from healthy sources.^17,18

I take care to frequently coach patients that there is no such thing as “good” or “bad” food. This only perpetuates eating disorders and unhelpful, temporary diets. Changing your diet is a lifestyle change. Fruit is a healthy source of sugar, vitamins, flavinoids, and nutrients when consumed in moderation. Many note how much better they feel eating primarily a ketogenic diet, which recommends eating the following distribution: 55-60% fat, 30-35% protein, and only 5-10% carbohydrates. Unless you’re an olympic athlete, if after careful inspection you realize your diet is 80% carbohydrates, you need to make a change!

Why Is Insulin Sensitivity Important and What Are the Benefits?

According to the American Academy of Family Physicians, poor insulin sensitivity and resistance are linked to higher rates of diabetes, hypertension, dyslipidemia (high levels of bad cholesterol and triglycerides), heart disease, and many other diseases. Decreased insulin sensitivity develops over many years, which is why having annual physicals and getting your labs checked every few years are so important. Those with a personal or family history of diabetes, obesity, polycystic ovarian syndrome (PCOS), gestational diabetes, or heart disease would be well served to take preventative measures.¹³

Having adequate insulin sensitivity has numerous benefits:¹⁶

• The cells of your body can use glucose more effectively.
• Reduces the co-morbid risks that follow diabetes, such as ulcers, infection, and poor wound healing.
• Better sleep and more energy during the day.
• The body is able to lose weight quicker and does not pack on the pounds as easily.
• Protects your heart and other organs from chronic disease.

Some medications can exacerbate insulin and sugar problems, such as Quetiapine (Seroquel) and Olanzapine (Zyprexa), to name a few. If you take several medications and suffer from poor insulin sensitivity, ask for a consult with your pharmacist.²⁰

The CDC recently published that 38% of U.S. adults have prediabetes or diabetes, based on their fasting glucose or A1c levels.¹⁵  This can largely be based on the socio-culturally accepted high-carbohydrate diet presented to Americans on a daily basis. Many genetic links have been identified, and the rates of insulin resistance are only increasing. Practicing the helpful tips in this article will help you avoid developing diabetes and re-establish a healthy relationship with food, sugar, and insulin. 

<p class="pro-tip">Learn more about <a href="/blog/reverse-insulin-resistance">reversing insulin resistance</a></p>

What can a continuous glucose monitor (CGM) tell you about your insulin sensitivity?

Signos uses an AI-driven app to provide real-time notifications about your glucose levels. As you eat and log meals in the app, it will notify you if your glucose levels spike in response to certain foods. Combined with a CGM, the app helps tailor personalized suggestions, including which foods trigger sugar spikes, when to eat them (or not), and when to exercise. This keeps you within your optimal weight loss range and helps you make micro changes. 

<p class="pro-tip">Learn more about <a href="/pricing">getting started with Signos</a></p>