Insulin resistance causes many problems throughout the body, so addressing it has a sizeable impact on our health.  One way in which insulin resistance can cause problems is through circadian disruption.  A new study found that insulin is the feeding cue that synchronizes feeding with the master clock.

To me, there’s nothing even remotely as exquisite as the circadian system.  When researchers describe it as a symphony orchestra, they really couldn’t  be more accurate.  Every cell, tissue, organ, signaling molecule, and hormone really has a part to play.

I don’t believe one can optimize health without taking circadian rhythms in to consideration. This is because it’s really difficult to completely isolate parts of the “orchestra” from others.  In the same way, I don’t think you can isolate certain foods or nutrients and say, “This fixes leaky gut” or “This causes leaky gut”.

The reason people fail so miserably at addressing leaky gut is because they ignore the circadian component.  The reason it’s so easy to ignore the circadian component is that it’s:

• Difficult to do
• Time consuming
• And doesn’t yield immediate results. 

The problem is, ignoring it virtually guarantees no results in the long term.

Insulin, the circadian clock, and leaky gut

There’s no better example of this than looking at the hormone insulin.  Once upon a time, we thought there was a circadian clock separate from the master clock called the food entrainable oscillator. 

Turns out it may not even exist, and this study identifies insulin as the primary circadian signal from feeding. This puts the problem with insulin resistance in to perspective.

Image source

Insulin is released when we eat and levels naturally plummet while we fast.  If we’re trying to sync up the master clock to when we eat, there really is no better way.  But what effects would we expect to see in the gut?

For one, we’d expect our circadian system to resist leaky gut when we eat.  I can think of no worse time to have a leaky gut.  Sure enough, the insulin signal helps ready the gut for what’s to come by decreasing leaky gut. Insulin is released before food even hits your stomach.

This makes insulin resistance a pretty big problem for leaky gut. Insulin resistance means your cells aren’t responding to insulin. If the cells in your gut aren’t listening, how would they know to prevent leaky gut?

Insulin resistance, hyperglycemia, and leaky gut

A recent study which I’ve referenced more than a dozen times illustrates this nicely.  High blood glucose in mice causes leaky gut. But if they’re treated with insulin at the same time, no leaky gut.  In humans, HgA1c is the strongest predictor of bacterial invasion from leaky gut. HgA1c essentially functions as a 3 month average of blood glucose levels.

Chronically high insulin, which precedes elevated glucose and Type 2 diabetes, slows GI motility.  This causes problems such as:

• Delayed gastric emptying
• Acid damage to the stomach
• Damage to the duodenum
• SIBO

So first you see motility impairment, which proceeds to leaky gut and much larger problems.

And there are other problems as well.  Artificial sweeteners stimulate insulin without the effect on blood glucose. So they can screw this signal up.  That’s because there appears to be communication between taste receptors in the tongue and the pancreas.

Therefore, you can consume as much fiber, glutamine, and probiotics as you want.  You can even avoid gluten, dairy, soy, or whatever you feel causes leaky gut. 

But if you don’t fundamentally address insulin sensitivity and behavior to match up with the circadian cycle, you’ll never solve your leaky gut problem.

The simple insulin resistance test you better ace!

Since insulin resistance is so common, and seems to drive leaky gut, it makes sense to have a way to measure it. Otherwise, how do you correct it? Fortunately, expensive or hard to find tests aren’t necessary to accomplish this task. There’s a simple equation using data most people have that does the trick.

The Triglyceride to HDL ratio(TG:HDL) is a useful and validated tool to identify insulin resistance. Values indicative of insulin resistance in different groups are:

• Children-1.36
• Non-hispanic Whites & Mexicans-3.0
• Non-hispanic blacks-2.0

Theses are good cutoffs indicative of people with insulin resistance, but the study population is often people with pre- or Type 2 diabetes. However, TG:HDL is also useful as a measure of insulin resistance in people without pre- or Type 2 diabetes.

Having Type 2 diabetes isn’t a prerequisite for insulin resistance. Insulin resistance typically occurs long before you are diagnosed by fasting glucose or HgA1c. Even in healthy people, the TG:HDL ratio is indicative of insulin resistance based on HOMA-IR, a test used in studies that you’ll likely never encounter.

A more recent study identifies a TG:HDL ratio of 1.0 as ideal from a cardiometabolic health perspective. This is the number I recommend people shoot. The more insulin resistant you are, the more likely you are to experience a large glucose spike after a meal.

Conclusion

Maintaining a healthy TG:HDL ratio pays off in spades when it comes to gut health. It’s quite easy to induce a temporary state of insulin resistance. In fact, most of us will do it at least a couple of times in the next 3 months. I recommend people who want to enjoy life and treat themselves from time to time maintain a TG:HDL ratio below 1.0. If you are generally stricter on your diet, you may not need to maintain yours that low.

My TG:HDL ratio is .51, and I don’t find it difficult to maintain that. I keep it that low by:

• Optimizing circadian rhythms
• Maintaining good sleep hygiene/prioritizing sleep
• Getting high levels of physical activity
• Maintaining muscle mass via exercise
• Eating a diverse diet with lots of fiber

There are certainly many ways to skin this cat. But finding out where you are is the first step in the process. Your TG:HDL ratio is simple to calculate and only requires testing you have already done. If you have this data, it’s in your best interest to use it.

Since insulin appears to be crucial to setting your circadian rhythms, maintaining insulin sensitivity is very important for gut health. Thus, you must fix insulin resistance to fix leaky gut.