Why We Get Sick: The Hidden Epidemic at the Root of Most Chronic Disease -- and How to Fight It by Benjamin Bikman PhD is a great resource to learn about insulin resistance

Introduction

Why We Get Sick by Benjamin Bikman PhD is a book primarily discussing insulin resistance and its role in certain diseases, and what we can do to prevent or reverse it. The author’s bio on the webpage of Brigham Young University says that he is a researcher studying the molecular mechanisms causing or contributing to metabolic disorders with a focus on the role played by insulin and ketones. The author is highly qualified to talk about the subject and this book is a great resource to learn about insulin and insulin resistance. The following paragraphs discuss the key learnings from the book.

What is insulin resistance?

Let’s begin with insulin. Insulin is a hormone involved in stimulating glucose uptake by the cell, signalling it to build things or grow and also influences the secretion of other hormones. Now let’s look at insulin resistance. Insulin resistance happens when certain cells, tissues become less responsive to insulin. The key features of insulin resistance is that higher than normal levels of insulin is circulating in the blood and insulin doesn’t function as it does normally. The following three examples from the book demonstrate the issue.

The first example is about the effects of insulin resistance on glucose uptake of a cell. Let’s say the cell normally takes in 5 units of glucose from the blood if its exposed to 5 units of insulin circulating in the blood. If the cell becomes insulin resistant then for the uptake of the same 5 units of glucose the cell needs to be exposed to higher amounts of insulin say 20 units.

The second example is that of a cell that makes up the lining of the blood vessels called an endothelial cell. Insulin stimulates endothelial cells to produce nitric oxide(NO) which may result in the dilation of the blood vessels. Dilating the blood vessels boosts blood flow through it. Let’s say normally 5 units of insulin stimulates the production of 5 units of NO. When the endothelial cells become insulin resistant, for the production of the same 5 units of NO the cell needs 20 units of insulin. In these two examples insulin became less effective in doing its job.

The third example which we are going to discuss shows insulin resistance potentially throwing off the balance in our bodies. Different tissues vary in the levels to which they become insulin resistant. Let’s take an example of a case of muscle tissue being insulin resistant whereas adrenal glands are sensitive to insulin as normal. If muscle cells are resistant to insulin it will have a reduced response to take up glucose in response to insulin. Since muscle is one of the bigger storage sites for glucose, it taking up less glucose can potentially lead to more than normal glucose levels in the blood. Our bodies need to keep glucose levels at a certain range. In order to do that it produces more insulin to compensate for its loss of function in muscle cells. With the excess insulin in the blood, muscle cells are stimulated to take in glucose. It in turn clears excess glucose in the blood, keeping it at a normal range. Now in this example, adrenal glands are not insulin resistant. Normally adrenal glands produce a hormone called aldosterone which signals kidneys to hold onto sodium, which inturn gets reabsorbed into our blood. Since our bodies need to maintain a certain level of sodium to water ratio in the blood, when there is more sodium we retain more water. This results in increased blood volume and potentially an increase in blood pressure. Since there is excess insulin in the blood it stimulates excess aldosterone production. It in turn drives up blood pressure. High blood pressure for prolonged periods is not good news for our bodies. This case shows insulin resistance interfering with the balanced functioning of our body.

What causes insulin resistance?

The book lists three primary causes of insulin resistance. These are too much insulin, stress and inflammation. These are called primary causes because each of these alone can cause insulin resistance, regardless of whether the other causes are present or not. As an example elevated stress can cause insulin resistance even if there wasn’t too much insulin or inflammation to begin with.

Too much insulin can be from eating a lot of sugar and/or from eating in short intervals throughout the day. Eating sugar drives up glucose circulating in the blood and our bodies typically respond with increasing the production of insulin. If there is more glucose then it calls for more insulin. So too much sugar results in too much insulin. Eating in short intervals throughout the day also results in elevated insulin levels for extended periods of time. After a meal it takes some time for glucose and insulin levels to peak and come back down to normal. If you eat again before the insulin levels have come down then it doesn’t get a chance to be at a normal level. It results in higher than normal insulin levels in our bodies throughout the day. Think of the result of this as the body building a tolerance to the effects of insulin. A tolerance to insulin keeps the activation form it in check. This is similar to how regular alcohol consumption leads to a tolerance to its effects.

Stress is also a primary cause of insulin resistance. Stress discussed here is not necessarily when you feel stressed from say a bad interaction. It includes stressors of the body like poor sleep which we may or may not be perceiving consciously. It can be measured as an elevation in hormones associated with stress like epinephrine(adrenaline) and cortisol.

An other primary cause is inflammation. Inflammation mentioned here is not necessarily when you have a cold or swelling in the body. Similar to stress it is like an elevation in the measures of biomarkers associated with inflammation. The book has great explanations of these and how these affect insulin. There are other causes discussed in the book which works in combination with these factors leading to insulin resistance. I suggest you check out the book if you would like to learn more.

Difference between type 1 and type 2 diabetes when it comes to the amount of insulin produced in the body

Type 1 and type 2 diabetes are different forms of diabetes. Both are characterized by higher than normal blood glucose levels. The difference in terms of insulin is in the two extremes. With type 1 diabetes there is very low insulin in the body whereas with type 2 diabetes there is high levels of insulin of insulin in the body. The book says that type 2 diabetes is a case of our bodies becoming highly insulin resistant that it loses its ability to control glucose levels as needed. Before there is full blown type 2 diabetes there are tell tale signs of it developing, many years in advance, which is a stage called pre diabetes. It is characterized by an elevation in insulin levels but glucose levels stay normal. To put in an other way, the body is becoming insulin resistant needing more insulin to do the same job as before. It is just that it hasn’t gone out of control yet.

What is the role of insulin resistance in some very serious chronic diseases like heart disease, dementia etc?

Insulin resistance is a cause or a major contributor to a variety of chronic diseases like heart disease, neurological disorders, reproductive health, cancer, obesity etc. The role of insulin resistance in these diseases are discussed in detail in the book. Here I am expanding a bit on cancer. The book says that there is evidence to challenge the general consensus that cancer is a result of genetic mutations or gene damage. Instead it says that it is a disease of metabolism. The author notes that this paradigm of cancer is controversial. Anyway, regardless of cause insulin resistance do play a part in cancer since it is a disease of uncontrolled cellular growth. Growth is stimulated by insulin and elevated glucose levels resulting from insulin resistance makes available to the cancer cells its primary fuel.

How to prevent or reverse insulin resistance?

First of all insulin resistance can be prevented or reversed, generally speaking. The author recommends lifestyle changes as an important factor in doing that. This involves a change in diet, exercise, reducing or quitting smoking, taking measures for better sleep etc. It is because our lifestyle is a major cause or contributor to insulin resistance. So making adjustments to our lifestyle will have major benefits for us. The adjustments in diet can be summarized as following diets with lower amounts of carbohydrate in it like low carb or keto diet and incorporating intermittent or time restricted fasting into our life. Some of the tips and tricks from the book are given below. The book has detailed discussions on these and much more. I recommend you check it out to learn more.

• The order in which we eat affects insulin sensitivity. The author recommends to eat protein and fats first then have carbs.
• There are different types of carbs. The ones with low glycemic load(GL) is better for insulin sensitivity. (An explanation about glycemic load and glycemic index from the book is noted below the list.)
• Having soluble fiber from fruits and vegetables helps.

Glycemic index(GI) is a measure of how quickly the carbohydrate in the food is broken down and absorbed as glucose in the blood. Glycemic load(GL) is a measure of how much carbohydrates is in the food that can become glucose in the blood. There is an example shared in the book of a watermelon with GI of 72 and GL of 2. It means that even though the carbohydrates in the watermelon can rapidly become glucose in the blood, the actual amount of carbohydrates is low enough to not really matter.

Conclusion

This book is great to learn about insulin, insulin resistance, its causes and associated problems and actionable advice about how to prevent or reverse insulin resistance. The paragraphs above summarize some of the information from the book but there is so much more in it. I highly recommend you check out the book.

Book discussed

• Why We Get Sick: The Hidden Epidemic at the Root of Most Chronic Disease – and How to Fight It by Benjamin Bikman PhD