What is insulin resistance? It’s when you need higher and higher levels of insulin for the same result – that is, to drive glucose into cells as fuel. It’s the law of diminishing returns; over time, insulin becomes less effective at lowering blood glucose and the cells are resistant to the insulin and unable to use it effectively leading to high blood sugar. Eventually you have high insulin and high glucose. This is bad because high insulin causes the ovaries to make excessive amounts of androgens. Insulin also gets the liver to make less sex-hormone-binding globulin (SHBG), the key protein that binds testosterone and keeps it from causing trouble. This combination results in more free testosterone charging around the bloodstream like a bull in a china shop. High glucose inches you toward pre-diabetes and diabetes.
So how does all this work? Insulin is made in the pancreas and under normal circumstances, its release is finely calibrated to produce just the right amount so that glucose is extracted from food in your gut, sent into your bloodstream, and then driven into cells, particularly the fat, muscle and liver cells. In other words, the main job of insulin is to regulate your blood sugar. Think of insulin as the knock on the door of your muscle, liver and fat cells. The cell hears the knock and opens the door to let in the glucose. Once insulin gets glucose inside the cell, the cell can proceed with tasks such as growth, movement and repair. With insulin resistance, insulin is banging on the door of the cell like an irate neighbour, yet the cell can’t be bothered with opening the door anymore, so the pancreas gets the message to make more insulin. And then we get on the merry-go-round of insulin knocking louder and louder. Consequently, insulin levels rise and the cell becomes “deaf” to insulin. Insulin is also a fat-storage hormone, so you deposit more fat, notably around your waist.
When you need higher and higher amounts of insulin to deliver glucose as fuel to your cells, you burn out the ability of pancreas cells to keep up with demand. When this happens you cannot stabilize your blood sugar within the normal range any more. Your blood sugar rises, initially to pre-diabetes levels and possibly to the diabetes range.
Insulin resistance is at the root of several serious problems, including excess weight, obesity, prediabetes, diabetes, dementia, Alzheimer’s, stroke and some cancers. It can lead to accelerated aging, wayward hormones and poor organ reserve.
Although it is unclear whether high androgens cause insulin resistance or insulin resistance causes high androgens, we do know that high insulin levels drive ovaries to make more testosterone. Insulin resistance is a major factor in metabolic syndrome, a group of ominous signs that are linked to a greater risk of diabetes and heart disease, which affects a growing population. I’ll talk about metabolic syndrome in the near future.
In summary, insulin resistance:
- Raises the activity of the enzyme chiefly responsible for estrogen production, which sets the stage for estrogen dominance and lack of ovulation and fertility.
- Enhances the activity of an enzyme that increases androgen levels.
- Lowers sex-hormone-binding globulin (SHBG), allowing more free testosterone to roam the bloodstream and trigger rogue hairs and pimples.
- Raises blood markers for inflammation, which initiate a perpetual cycle of inflammation.
So what causes excess androgens? In a nutshell, genetics, chronic stress and excess body fat all contribute. Stay tuned to future posts to find out how you can combat excess androgens.
Next week we’ll talk about the other major effect of excess androgens, PCOS which is one of the leading causes of infertility in women.
Until next time ….