Insulin resistance

What is Insulin?

Insulin is a hormone that is released from the pancreas when we eat food containing sugar. It regulates the blood sugar (glucose) by:

• The food you eat is broken down into sugar
• Sugars enter the blood stream, which signals the pancreas to release insulin
• Insulin helps glucose to enter the cells to be used for energy
• Insulin signals the liver to store left over glucose for later use
• Glucose enters the cells and levels in the blood decrease, signalling insulin to decrease also
• Lower insulin levels alert the liver to release stored glucose, so energy is always available, even if you haven’t eaten for a while.

What is insulin resistance?

Insulin resistance occurs when the cells in muscles, fat and liver start to ignore the signal that insulin is trying to send out – to move the glucose form the bloodstream into the cells. When the cells don’t respond to insulin’s signals, too much glucose remains in the blood. I other words:

• A lot of blood sugar enters the bloodstream (usually from the food we eat)
• The pancreas pumps out more insulin to get sugar into the cells
• Over time, the cells stop responding to the insulin – they have become insulin resistant
• The pancreas keeps making more insulin to try to get the cells to respond
• Eventually the pancreas can’t keep up and blood sugar keep rising.

This increased blood sugar in the blood needs to be moved to the cells as quickly as possible. The increase in insulin is also telling the liver to store more glucose in the muscles; when they are full, the excess blood sugar is stored as fat, leading to weight gain. This then sets the stage for pre-diabetes and type 2 diabetes. (1)

High risk factors for insulin resistance include:

• Being 45 or older
• Having a high BMI
• Having a parent or sibling with diabetes
• Having a sedentary lifestyle
• A personal history of gestational diabetes
• A personal history of heart disease or stroke
• Medical conditions such as high blood pressure and high cholesterol
• Polycystic ovary syndrome (PCOS)
• Cushing’s syndrome (when the adrenal glands produce excess cortisol)
• Sleep apnoea and other problems with getting enough sleep

What can we do?

If you are insulin resistant, you want to become the opposite – insulin sensitive. This occurs when the cells are more effective at absorbing blood sugar, so less inulin is needed. So, how can we become more insulin sensitive?

• Watch your carbohydrate intake. Whole foods such as fruit, vegetables, whole grains and legumes contain carbohydrates and should be included in your diet, however the amount of carbohydrates differs for each person.

There are different types of carbohydrates – sugars, starches and some types of dietary fibre. Packaged and processed food contain refined carbohydrates and added sugars. This includes foods like bread, pasta, cakes and biscuits, potato chips, pastries and take away foods.

• Eat Low GI and GL foods. The glycaemic index is a way of ranking carbohydrate containing foods according to their effect on blood glucose. Eating foods that are low GI has a positive effect on blood glucose.

Foods are given a number from 0-100 according to how fast their carbohydrate is converted to glucose and enters the bloodstream. The lower the number, the slower the rise in glucose. The lower the number, the gentler the effect on insulin.

• Low GI foods have a GI of 55 or less.
• Moderate GI foods are 56-69
• High GI of 70 or above.

You can use a great interactive database of GI tested foods by Sydney University here – https://glycemicindex.com/. Why not check the GI of some foods that you commonly eat?

• Exercise – Physical activity makes your muscles more sensitive to insulin. Don’t wait until you are diagnosed – the earlier you take action and start moving more, the better off you will be. Dietitians Australia recommends at least 30 minutes of exercise most days.
• Lose weight. There are many ways lose weight and many different diets out there, but which one is right for you? Request an appointment with one of our qualified nutritionists or naturopaths to work out the best path for you.
• Snack less. Snacking has become more prevalent now than it was when our grandparents were growing up. At some point, marketing started to tell us that we needed to eat snacks in between meals and that we should eat their conveniently made and packaged snack foods. Unfortunately, when we snack, it doesn’t give time for our insulin levels to drop. Try to eat according to when you are hungry, not when the clock tells us to eat. By listening to your body’s cues about when to eat, we can reduce the snacks and help to lower insulin.
• Reduce stress. Stress means that our bodies create more cortisol to help us cope with the stress. Higher levels of cortisol have a negative impact on insulin and thus disrupts the balance of blood sugar. (3) Click here for some tips on reducing stress.
• Get enough sleep. Poor sleep is a risk factor for increased blood sugar. Even partial sleep deprivation over one night increases insulin resistance. (4) See our tips for a restful sleep here.

References:

1. 2021, Centers for Disease Control and Prevention, ‘Insulin Resistance and Diabetes’, viewed on 3 November 2022, https://www.cdc.gov/diabetes/basics/insulin-resistance.html#:~:text=Insulin%20helps%20blood%20sugar%20enter,blood%20sugar%20for%20later%20use
2. 2022, Harrar S, “What to Know About Insulin Resistance’, Endocrine Web, viewed on 3 November 2022, https://www.endocrineweb.com/conditions/type-2-diabetes/insulin-resistance-causes-symptoms
3. 2022, Yaribeygi H et al, ‘Molecular mechanisms linking stress and insulin resistance’. EXCLI Journal, 21:317-334, viewed on 3 November 2022, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8971350/
4. 2022 Pacheco D, ‘Sleep and Blood Glucose Levels’, Sleep Foundation, viewed on 3 November 2022, https://www.sleepfoundation.org/physical-health/sleep-and-blood-glucose-levels#:~:text=Decreased%20sleep%20is%20a%20risk,diabetes%2C%20a%20blood%20sugar%20disorder.