What is Insulin Resistance and Sensitivity?
Blood sugar management has become a buzzphrase in recent years. And rightfully so, with increased rates of metabolic syndrome, diabetes, and insulin resistance. What many may be less familiar with is how blood sugar and insulin are connected, what insulin resistance means, and whether it’s something we can assess for early detection and management of our health and related risks. Because, spoiler alert, there is a lot we can do from a food and lifestyle perspective to improve, and even reverse, this condition.
Blood Sugar
To get us started, let’s review a bit more about how blood sugar (also referred to as blood glucose) functions in the body. When we eat, food begins to break down as soon as it encounters digestive enzymes and stomach acid, first in our mouth and then in our stomach. Carbohydrates are the easiest nutrients to break down and have the largest impact on blood sugar levels because carbohydrates are primarily made of glucose. These tiny glucose particles are released into our bloodstream to serve as a source of energy for cells throughout our entire body. But to be utilized as such, our cells need to be able to ‘take in’ that energy. This is where insulin comes into play.
Insulin
Insulin is a hormone released by the pancreas, and its primary role is to regulate blood sugar levels by moving glucose into our cells, to both provide fuel for our cells and tissues and to keep blood sugar levels from rising too high. When glucose levels in the blood are elevated, which occurs soon after we eat a meal, insulin is released from the pancreas and binds to cell receptors throughout the body to allow glucose to move inside. Insulin enables the body to keep blood sugar levels within an optimal range and to use glucose for energy. In this ideal scenario, our cells are responsive to insulin, aka they are insulin sensitive (i.e., not resistant).
Insulin Resistance
Insulin resistance, on the other hand, is a situation in which the cells and tissues of our body are less responsive to the presence of insulin. As a hormone, insulin needs to bind to cells to do its job of moving sugar out of the bloodstream and into the cells. In a state of insulin resistance, even when blood sugar levels are elevated and insulin is released, the body is less efficient at moving this sugar (aka glucose) into the cells for energy. If glucose stays in the blood, blood sugar levels remain high, and our cells don’t get the energy they need. The presence of excess sugar in the blood is problematic for other organs and tissues repeatedly exposed to this “high blood sugar” environment. When this process continues over time, such as in the case of unrecognized or untreated insulin resistance or type 2 diabetes, adverse health outcomes can arise in various body systems (heart, kidneys, nerves, eyes, brain, etc.)
Standard Labs for Assessing Blood Sugar
There are ways to assess our body’s effectiveness at keeping blood sugar levels in the optimal range. The first and most common is a fasting glucose lab. This lab is typically run as part of a metabolic blood panel. A fasting glucose level of less than 100 mg/dL is considered within the optimal range. This gives a one-time reading of where someone’s blood sugar level is after, ideally, an 8-12 hour fasting period. If levels are borderline or higher than 100 mg/dL, this may indicate insulin resistance. Another more comprehensive lab marker to assess is hemoglobin A1C. This test measures a three-month average of blood glucose values. It is reported as a percentage, and optimal values are below 5.6%. A result of 5.7% or above would indicate a need for intervention, such as dietary and lifestyle changes, for improved blood sugar management.
Risk Factors and Signs of Insulin Resistance
While the concept of insulin resistance is relatively easy to understand, determining who is insulin resistant is more complicated. Tests to measure insulin levels do exist, but there is no standardization (i.e., process to ensure consistency) across testing methods used to assess insulin.
A more accessible approach to considering whether someone may be insulin resistant is to understand the conditions that put one at risk and to identify the signs. Obstructive sleep apnea, polycystic ovarian syndrome (PCOS), Cushing’s syndrome, and metabolic-associated fatty liver disease are conditions often correlated with an increased risk of insulin resistance. It’s believed there are no clear symptoms of insulin resistance, but a variety of possible signs include skin tags, dark skin patches that appear in skin folds, blurred vision, increased thirst, frequent urination, slow healing cuts, skin and vaginal infections, irregular periods, weight gain, increased hunger, fatigue, and headaches. As evidenced, various body systems are affected, and some of these indications may arise for other reasons, so it’s important to look for more than one while assessing other risk factors.
4 Pillars of Wellness
With risk in mind, let’s shift our focus to lifestyle factors that help reduce risk and can, in fact, reverse insulin resistance. At Summerfield, we refer to the primary aspects of lifestyle that influence health as the 4 pillars of wellness: nutrition, physical activity, stress, and sleep. These pillars of wellness are vital for every person to consider, and they are particularly important in blood sugar management and reducing the occurrence of insulin resistance.
Nutrition
There is much we can do with the foods we choose and our daily approach to nutrition. Selecting fiber-rich complex carbohydrates, such as whole grains, beans, legumes, fruits, and starchy vegetables, will have less of an impact on our blood sugar than more processed carbohydrates, such as bread, cereals, rice, pasta, and sweetened food and drinks. Also, pairing our carbohydrate sources with proteins (lean meat, seafood, eggs, and soy) and fats (avocado, nuts, seeds, and olive oil) supports a more stable rise and fall in blood sugar levels after meals and snacks. Ensuring we don’t wait too long to eat and then eat large amounts of food at one time is another helpful strategy for minimizing big swings in blood sugar levels and, thus, an excess demand for insulin. Eating a balanced meal or snack every 3-5 hours can also help keep blood sugar levels balanced throughout the day.
Physical Activity
Physical activity can be thought of as a blood sugar-lowering superpower when it comes to supporting the body’s use of glucose. Active muscles require more sugar for energy than muscles at rest. When our body is active, muscles have a sort of “back door” ability to move sugar out of the bloodstream and into their cells without the need for insulin. This means if we’re able to take a walk after a carbohydrate-rich meal, our blood sugar levels will return to the optimal range more quickly than if we remained inactive after the meal. Since insulin resistance means our cells are less responsive to insulin, having this alternate way (that doesn’t require insulin) to move glucose out of the bloodstream is a highly effective management tool. Whether you like to move your body by walking, swimming, doing yoga, lifting weights, or attending a workout class, any type of activity done regularly is beneficial, and maintaining lean muscle mass as we age means a continued ability to have this ‘superpower’ work in our favor.
Stress
Stress is another factor that influences whether insulin can work properly. In times of intense or prolonged stress, our body releases hormones like cortisol and adrenaline, which are part of the body’s fight-or-flight response. Both hormones increase blood sugar levels, as the message in the body is that we need access to quick fuel in this stressful state. However, when under stress, elevated cortisol levels make our cells less responsive to insulin, thus creating a state of insulin resistance. While we can’t always control whether stress occurs, we can manage our response to it. Utilizing practices like deep breathing, meditation, taking a walk, listening to music, and spending time in nature can provide a sense of calm that allows the body to reregulate to a less stressed state. Engaging in activities that manage and reduce stress regularly helps us become more resilient to the effects of stress. It lessens the amount of time spent in a stressed state, thus lessening the impact on our body and health.
Sleep
Sleep is the fourth and final pillar of wellness that factors into overall health and has unique considerations for insulin resistance. Poor quality and/or inadequate sleep also influence blood sugar and cortisol levels and our cell’s response to insulin. Our body is meant to function according to a circadian rhythm, which operates like an internal clock that uses hormones as messengers to all the cells and organs in the body. When things shift away from this optimal rhythm, there is a domino effect that doesn’t work in our favor. Researchers have found higher rates of diabetes among individuals who consistently sleep less than 6 hours per night. Sleeping 7-9 hours each night is a helpful defense against this risk. Strategies like having a consistent sleep and wake time, engaging in wind-down activities, and having an environment conducive to sleep (dark, quiet, and comfortable) are factors to consider that promote optimal sleep.
Interconnectedness of the Pillars
Each of the four pillars of wellness has its own unique impact on insulin resistance, and they are also interconnected. If we don’t sleep well, data shows we will have increased cravings for high-carbohydrate foods, indicating a connection between the sleep and nutrition pillars. If we are stressed, we may not feel we have time to exercise, even though activity helps with stress management and lowering blood sugar levels. Recognizing what support is needed for each pillar to remain balanced helps us to optimize the foundation of wellness that these four pillars create.
If this information has you wondering whether you might be experiencing insulin resistance, the good news is you can start making small adjustments today! There is no need for a diagnosis of insulin resistance to implement changes that better support the pillars of wellness and provide full-body benefits. Our Summerfield dietitians are skilled at customizing their approach to each patient, and we’d be happy to join you on the journey of blood sugar management and reducing insulin resistance.