The meaning of insulin resistance can be simplified as : due to certain circumstances and changes in biology, the cells in the body have become resistant or less responsive to the hormone insulin.

In the case of insulin resistance, your body will try to compensate for these less responsive (or insulin resistant) cells by increasing the amount of insulin produced in an attempt to get enough insulin into the cell to do its job.

Elevated insulin is detrimental to our health. These are just some of the negative impacts high insulin can have on our health, but the list goes on:

• rapid increases in fat gain and difficulty losing weight
• lethargy
• elevated blood pressure
• inflammation
• fatty liver
• reproductive issues and erectile dysfunction
• increases in bad cholesterol
• weakened immune system
• increased risk of cancers
• cardiovascular disease
• cognitive issues

What are the main causes of insulin resistance?

There are several factors that cause humans to become insulin resistant. Frontline workers are exposed to these factors on a regular basis for the duration of their career- inside and outside of the workplace.

1. Too much insulin causes insulin resistance

This might sound confusing-lets break it down. When you eat carbohydrates, they are converted into glucose which is energy for your cells. Glucose needs insulin to be absorbed into your cells. Insulin is a GOOD thing and we absolutely need it. Too much insulin is a BAD thing.

If we consume carbohydrates (in amounts greater than our specific needs or that your body requires) several times a day, we will be in a constant state of elevated insulin. After eating carbohydrates, insulin is generally elevated for 3 to 4 hours and then it returns to normal. If we continually ingest carbohydrates every few hours (or even worse, we graze on food that consists of carbohydrates between meals) we will have consistently elevated insulin levels, which can lead to insulin resistance and all of its nasty side effects.

2. High stress levels (too much cortisol)

Keep in mind cortisol is important and without it, you simply would not survive.

TOO much cortisol is the problem- and a big one at that.

As a frontline worker, your cortisol is consistently elevated during work hours and shifts, and lingers even on your days off.

The stress hormone cortisol can make it harder for insulin to do its job for three main reasons:

1. Cortisol causes the liver to dump glucose into the bloodstream to give us energy during times of stress. This dumping of glucose increases blood sugar, and therefore requires insulin to utilize this blood sugar as energy. Several dumps of glucose = several spikes in insulin and as we now know, TOO much insulin causes insulin resistance.

2.Cortisol breaks down muscle tissue to create glucose. The more muscle someone has, the more insulin sensitive they are (generally speaking) and they have better response to insulin. Cortisol eats away at muscle (amino acids) which can lead to insulin resistance over time.

3. Cortisol blocks or impedes cellular processes that help us to uptake glucose. When these cellular processes are stopped or interfered with, insulin cannot do its job at the cellular level and the cells become less responsive to insulin.

3. Poor sleep quality/reduced sleep duration

The number of hours of sleep someone requires will be an going debate forever. Is it six? Or is it the standard eight hours of sleep we all need? Regardless of the real answer, one thing will always remain true when it comes to frontline workers: they are sleep deprived in regards to both duration, and quality.

Whether its being woken up by tones during a 24 hour shift for firefighters, or being awake for all hours of the night during night shifts for paramedics, police officers, and nurses. The negative hormonal changes associated with poor sleep are clear.

Just one week of sleep deprivation is enough to make the body up to 30% insulin resistant vs a normal sleep week. (Spiegal, K., Leproult, R., and Van Cauter, E., Impact of sleep debt on metabolic and endocrine function. Lancet, 1999. 354(9188):p. 1435-9.)

In addition, just two nights of poor sleep (deprivation and/or quality) is enough to induce short term insulin resistance. (Sweeney, E.l., et al., Skeletal muscle insulin signaling and whole-body glucose metabolism following acute sleep restriction in healthy males. Physiol Rep, 2017. 5(23).

These are the most common causes of elevated insulin and insulin resistance for first responders but there are many more factors that can lead to it. Some of which include inflammation (a main culprit of insulin resistance), certain medications, aging, lifestyle and habits such as alcohol and smoking, and many more.