Reducing insulin resistance for weight loss
Key Takeaways
Insulin is a hormone that helps keep blood sugar from rising too high, by stimulating tissues in the body to take up glucose from the blood.
Insulin resistance occurs when these tissues don’t respond normally to insulin.
The body responds to insulin resistance by producing extra insulin. At first, this may keep blood sugar levels within a normal range. As insulin resistance becomes more severe, blood sugar levels will begin to rise.
A test called HOMA-IR is used to determine how sensitive your tissues are to insulin, using the levels of both insulin and glucose in your blood.
High levels of insulin promote storage of calories as fat, so insulin resistance may lead to weight gain. People with insulin resistance tend to find it hard to lose weight.
Medications such as metformin can help to restore insulin sensitivity in the tissues. Another class of medications, known as GLP-1 RAs, can be used to help promote weight loss.
What is insulin resistance and how does it affect weight loss?
Insulin is a hormone that’s crucial for regulating blood sugar levels. It’s produced after eating, when blood sugar levels begin to rise. Normally, the body’s tissues will respond to insulin by taking up sugar from the blood, and either using it for energy or storing it as fat. This prevents blood sugar from rising too high.
Insulin resistance occurs when the tissues become less responsive to insulin. This means that, even when insulin is present, the tissues won’t take up as much sugar from the blood. As insulin resistance becomes more severe, too much sugar is left in the bloodstream, leading to prediabetes or type 2 diabetes. A test called HOMA-IR is used to determine how sensitive your tissues are to insulin, using the levels of both insulin and glucose in your blood.
When the tissues are resistant to insulin, the body will respond by making more insulin, in an effort to keep blood sugar levels in the normal range. Insulin also acts as a growth hormone – it promotes the storage of calories as fat. When insulin levels are higher, people feel hungry more often, and they tend to gain weight as their body is primed to hold on to fat — weight loss becomes significantly more challenging.
Being overweight tends to lead to insulin resistance. This can easily become a vicious cycle – insulin resistance leads to weight gain, and weight gain leads to more insulin resistance. It can be very frustrating to find yourself in this cycle.
How do you detect insulin resistance?
The most common tests for diabetes and prediabetes include fasting plasma glucose, which measures your blood sugar level when you haven’t eaten recently, and hemoglobin A1c (HbA1c), which checks your average blood sugar levels over the past few months. People with moderate to severe insulin resistance will show high levels on these tests.
However, if you have insulin resistance, but your pancreas is still able to produce enough insulin to overcome the resistance of the tissues, then these tests will show normal results.
To help detect insulin resistance at an earlier stage, a test called HOMA-IR is used. This involves testing the levels of both glucose and insulin in your blood. If your insulin level is higher than expected for the amount of glucose in your blood, this indicates that you have insulin resistance, and your pancreas is trying to compensate by producing extra insulin.
In some cases, insulin resistance is genetic. It can also be associated with certain medical conditions, like polycystic ovary syndrome (PCOS). However, insulin resistance is commonly caused or exacerbated by lifestyle factors, including a high sugar diet and lack of exercise. Being overweight, especially if the excess weight is primarily carried around the waist, is strongly associated with insulin resistance.
Symptoms of Insulin Resistance
Early on, when the body is still producing enough insulin to keep blood sugar levels within the normal range, insulin resistance may not produce any clear symptoms. Even if you don’t have any physical signs, you might still have insulin resistance.
However, some people do experience certain signs of this condition. These insulin resistance symptoms for females and males are generally the same, and may include:
Weight gain, especially around the midsection (the abdomen)
Increased numbers of skin tags (small, painless growths on the skin)
Darkening of the skin of the armpits and back of the neck (known as acanthosis nigricans)
High blood pressure
In people who have these signs, a HOMA-IR blood test is indicated, to check for insulin resistance.
Insulin and weight loss
Insulin promotes the storage of calories as fat. In people with insulin resistance, insulin levels are generally higher. This is how insulin resistance leads to weight gain, and makes weight loss more difficult. Even when eating a low calorie diet, people with insulin resistance may find that excess weight is more stubborn and harder to lose.
Because carrying excess weight is also associated with insulin resistance, this can sometimes lead to a vicious cycle. Insulin resistance causes weight gain, and weight gain causes more insulin resistance. This bidirectional relationship is believed to be responsible for the strong link between obesity and insulin resistance.
If you’re looking to reduce insulin resistance, there are a few healthy lifestyle changes that can help:
Eat a low sugar diet (or low carb diet). When you eat sugar, your body has to produce a lot of insulin in order to process this. Simple carbohydrates, such as starches, are converted into sugar very quickly, and have a similar effect. Eating less sugar helps to reduce the amount of insulin that your pancreas needs to produce, which has a beneficial effect on insulin resistance.
Exercise. Physical activity promotes insulin sensitivity in the tissues. Aerobic exercise, which causes your heart rate and breathing to speed up, is the most beneficial type for this. Aim to get at least 20 to 30 minutes of aerobic physical activity on most days. Add strength training to increase lean muscle mass.
Try intermittent fasting. A technique called intermittent fasting helps many people to lose weight, and has also been shown to improve insulin sensitivity. This involves restricting your eating window to a certain number of hours each day – for example, you might eat only between noon and 8pm. Sometimes, certain days of complete fasting or restricted food intake are also included. A health coach can work with you to find an intermittent fasting schedule that can help you.
Get enough sleep. A lack of sleep has been shown to lead to insulin resistance. Ensure that you’re getting eight hours of high-quality sleep every night to help maintain insulin sensitivity in your tissues.
Manage stress. When you’re stressed, your body secretes stress hormones such as cortisol, which reduce insulin sensitivity in your tissues. It’s essential to find ways to reduce the amount of stress in your life, and to manage stress when it does arise.
Role of GLP-1 RAs and Metformin in reducing insulin resistance and weight management
There are certain medications that can be helpful for people with insulin resistance.
Metformin is a common medication that acts in part by increasing insulin sensitivity in the tissues.
Thiazolidinediones (TZDs, such as pioglitazone and rosiglitazone) are another type of medications that increase insulin sensitivity. These types of medications are known as insulin sensitizers, and are typically used to help lower blood glucose in people whose sugar levels are too high.
Another type of medication can also be used to help with blood sugar control and weight management. These are known as GLP-1 receptor agonists, or GLP-1 RAs. Medications in this class include semaglutide and liraglutide. They have a variety of effects, including slowing down stomach emptying and acting in the brain to reduce food cravings. This causes people taking GLP-1 RAs to feel full for longer and eat less. As a result, they tend to lose weight, which helps to reduce insulin resistance.
In addition, because of the slower stomach emptying, there is less of a spike in blood glucose right after a meal. Instead, blood sugar goes up more gradually. Whenever there’s a spike in blood glucose, insulin levels will also spike. These insulin spikes can worsen insulin resistance. With the more gradual changes in blood sugar, the insulin spikes are avoided, which helps to promote insulin sensitivity in the tissues.
For people with insulin resistance who are struggling with weight loss, GLP-1 RAs together with metformin and lifestyle changes may be used alongside a healthy lifestyle to help a person achieve a healthier body weight. Clients in our NOVI Optimum Plus medical weight loss program receive these medications, along with health coaching and other support for making healthy lifestyle changes.
