There’s a tremendous amount of confusion as it pertains to what causes leaky gut. If you look at the approaches most people take to correct it, you’d think it was a glutamine or probiotic deficiency. Or maybe it’s fungal overgrowth or carbs. Fortunately, a newly published study tackles the problem.
In Risk factors associated with intestinal permeability in an adult population: A systematic review, we’re getting close to an answer. The authors of this paper reviewed the literature and identified several risk factors for leaky gut. As a result, we see that what causes leaky gut is more than likely something no one wants it to be: our behavior.
I spoke with the lead researcher Brad Leech on the project. He states, “Most practitioners think leaky gut symptoms are issues like bloating, reflux and stomach pain. However, when we looked at all possible risk factors and indicators for leaky gut it was:
- Hyperglycemia/insulin resistance
- Anthropometric measurements resembling obesity
- Advanced disease severity with comorbidity
- The consumption of a Western-style diet
These were the strongest risk factors for leaky gut.” Note: If you haven’t yet, check out and like his Facebook group Leaky Gut Research where he shares many of his research papers.
It’s quite interesting and to some may be a shock. As a result, some may be overwhelmed and others frustrated. But this is actually fantastic news.
All of these factors are under your control. You may not like what you have to do to correct them, but those willing to do it can see phenomenal results. Therefore, the power is actually in your hands. Let’s dig in to the paper.
The biggest risk factors for leaky gut
Most of the major risk factors for leaky gut are the same things that plague Western countries. For instance, alcohol consumption was a big one, and all components of the metabolic syndrome as well. This includes:
- High blood pressure, particularly diastolic blood pressure
- High blood sugar
- Increased waist circumference
- High triglycerides
- Low HDL cholesterol
Other factors associated with leaky gut include having one or more chronic diseases, age, and inflammatory markers. In other words, it appears leaky gut is a component of chronic disease. Furthermore, leaky gut is more strongly associated to markers such as triglycerides and waist circumference in people with chronic disease.
Strengthening the importance of behavior in leaky gut, a few dietary factors are important. High calorie intake (>2616cals), low total protein intake, high animal protein intake, and low fiber intake all increase the risk of leaky gut. No surprise there.
Conversely, some of the things many believe to be indicative of leaky gut did not share an association with it in the general population. Specifically, various GI symptoms such as:
- Abdominal cramps/pain
In people with IBD, IBS, or dysbiosis, leaky gut did associate with the severity of disease and symptoms.
What causes leaky gut: A deeper look
So all of this seems to point to our behavior as a prominent cause of leaky gut. In addition, correcting things known to improve with a better lifestyle reverses leaky gut. This includes lowering BMI, correcting high blood glucose, and lowering inflammation.
But how does it work? I think one huge factor is circadian rhythms. The organs throughout the body turn on and off at the appropriate times. This allows them to build up resilience right before they’re put to use.
However, it’s not like your gut has a watch. It doesn’t know what time it is, it needs some signal to tell it what time it is. In order for the gut to know when to shutdown for repairs, it needs to know when you’re eating and when you’re not. Consequently insulin was recently identified as that time cue.
It makes sense. We secrete insulin when we eat, and we don’t when we fast. What better way to signal that it’s time to eat? Unfortunately, insulin helps regulate whether we burn or store what we eat. So there are a number of factors that help regulate it:
- What and how much we eat
- Our muscle mass
- Physical activity levels
- Meal timing and frequency
- Light exposure
Other than fasting insulin, there really isn’t a useful measure of insulin for the general population. So we have to rely on surrogate markers such as blood glucose, triglycerides, and Triglyceride:HDL ratio to determine insulin sensitivity.
A high TG:HDL ratio (>2.5 in women, >3.5 in men) indicates insulin resistance. Interestingly, high triglycerides and low HDL are both listed as risk factors for leaky gut in the above review.
How it all works
I’ve covered how insulin resistance and hyperglycemia cause leaky gut many times. It’s important to differentiate the type of hyperglycemia that causes leaky gut and the kind that doesn’t. There may be some mild leaky gut from bingeing on a huge piece of cake, but this isn’t likely a big issue in an otherwise healthy person.
When there’s sufficient insulin present and cells respond to it, hyperglycemia doesn’t cause leaky gut. However, if there’s no insulin or cells are insulin resistant, all bets are off. Furthermore, if you are insulin resistant, every time you splurge, you’ll likely get leaky gut.
The easiest way to correct insulin resistance is to lose weight. A great deal of insulin resistance comes down to how much fat we hold in comparison to our total fat capacity. Some people are genetically predisposed to holding more fat, others less. So it’s not like I can say you need your bodyfat below a certain percentage, it’s different for everyone.
Exercise increases the amount of glucose your muscles can store and empties out those stores. Muscle is the largest sink for excess glucose. So those who exercise are generally more insulin sensitive than those who don’t.
Alternate day fasting is another effective way to improve your sensitivity to insulin. People who did alternate day fasting saw a 52% drop in fasting insulin compared to a 14% drop in people who calorie restricted. This happened despite the same average daily calorie intake.
There are actually quite a few things you can do to Stop Leaky Gut. And most of them don’t require restricting foods or spending $300 a month on supplements.
Researchers are just beginning to peel the onion to determine what causes leaky gut. The old paradigm of food restriction and costly supplements is being replaced with circadian optimization, exercise, and sleep hygiene. Based on what I’ve seen, the results aren’t even remotely comparable. The latter outperforms the former in nearly every way.
The great thing about this is that your health is in your own hands. If you have any of the components of the metabolic syndrome, correct them. Poor sleep? Work on it. Ignoring circadian rhythms? Start paying attention.
Unfortunately, leaky gut is far worse when you have one or more chronic diseases. That’s why these biomarkers more strongly predict leaky gut when you have one or more chronic conditions. Correcting your lifestyle corrects these biomarkers, corrects chronic disease, and thus, corrects leaky gut.