The fall season is the time when stores increase their supply of baking ingredients, pies, candy, and overall junk food. It is tempting for most of us to dig into these sugary delights, especially if we have kids or are planning a small get-together with friends. While satisfying our sweet tooth seems like an innocent indulgence, we must be careful not to overdo it. And if ever there’s a time to overdo something, the fall season and approaching holidays are a favorite excuse. Keep in mind that habitual snacking on sugary foods will negatively affect your blood sugar throughout the day (even if you have normal blood sugar). In fact, blood sugar can impact the health of our gut and microbiome, even in healthy people. The reverse is also true: people with current gut issues can experience blood sugar problems. Worse still, there are countless people out there who are unknowingly experiencing large swings in their blood sugar, thus risking their gut health. Lastly, health conditions that arise from high blood sugar (diabetes, obesity, neuropathy, and CVD) account for over 3 million deaths per year. Clearly, blood sugar issues can cause lasting health effects for all people, whether or not a person has an existing condition. Let’s dive in to see how this works.


What Causes High Blood Sugar?

Carbohydrates from our diet provide the glucose that our cells need for energy. This becomes a problem when glucose cannot enter our cells and instead hang out in our bloodstream, causing high blood sugar. 

But wait, doesn’t insulin push glucose into our cells? Why would insulin not do its job? The more glucose we have in our bloodstream, the more insulin our pancreas pumps out to handle it. However, our pancreas is not a bottomless pit of insulin, and eventually, insulin production slows down. It simply cannot keep up with demand. This is insulin resistance, and as a result, excess glucose builds up in our bloodstream causing high blood sugar.

Not all carbs will spike our blood sugar, however. Processed carbs (seen in white bread and baked goods), as well as added sugars (seen in candy, pastries, snack foods, and several beverages), increase our blood sugar more rapidly than do complex carbs (seen in legumes, whole grains, and vegetables). Complex carbs increase our blood sugar slowly and steadily throughout the day, providing us with sustained energy and balanced functioning. This steady blood sugar cycle is healthy and will not disrupt our gut. 


Blood Sugar and Leaky Gut

Researchers have discovered that a diet high in processed carbohydrates is associated with gut dysfunction and can lead to leaky gut. Researchers have found that excess glucose in our diet, from processed carbs and added sugars, cause damage to intestinal cells and alter our gut microbiome. This is accomplished as excessive sugar intake increases inflammation and breaks down our intestinal barrier. Amazingly, this can occur with or without high blood sugar! Commonly, a person can have normal levels of average daily blood sugar, while still experiencing spikes and dips throughout the day. Even the occasional spike in blood sugar harms our intestinal cells. 

The reverse is also true. Those who already have a leaky gut or an imbalance of gut bacteria are at risk for developing high blood sugar. This is because the harmful bacteria present in these conditions release a toxin called lipopolysaccharide (LPS). LPS toxins damage our intestinal barrier, leak into our bloodstream, and cause insulin resistance and high blood sugar.


What Is Leaky Gut Syndrome?

Our intestine is supposed to allow nutrients from our food (vitamins and minerals) to enter our bloodstream. The tight barrier of intestinal cells only allows these microscopic nutrients to pass through while preventing larger particles from entering our bloodstream. Our intestinal barrier is said to be selectively permeable, only allowing certain compounds to pass through. However, studies show that excess sugar in our bodies breaks down this tight barrier of cells, allowing larger particles to escape our intestine and enter our circulatory system where they don’t belong. This is called increased permeability, or leaky gut.

These larger particles include bits of undigested food, harmful bacteria, and the toxins produced by bacteria. Once they all enter our blood, they wreak havoc throughout our body, causing symptoms like bloating, bowel problems, fatigue, food sensitivities, joint pain, weight gain, headaches, brain fog, skin problems, and more. These are the common symptoms of leaky gut syndrome

Further, our immune system launches an attack on these “foreign” particles, which increases inflammation and perpetuates leaky gut. Lastly, excess sugar in our diet feeds the harmful bacteria in our gut, displacing our beneficial bacteria. This causes a microbial imbalance which further damages our gut lining, increases intestinal permeability, and increases inflammation. As you can see, compromised gut lining, increased inflammation, and microbial imbalance all play a role in the ongoing damage and progression of leaky gut syndrome.

It’s important to note that leaky gut syndrome is not only caused by diets high in sugar. This condition is also brought on by low-fiber diets, chronic stress, NSAID medications, antibiotic use, and bacteria or yeast overgrowth.


If overindulgence was a season, it would run between October and December. This is the time of year when healthy habits are set aside and poor habits are justified. However, our bodies don’t change their habits and the extra burden we place on them due to our high sugar intake compromises our gut health. As we have seen, even those with normal blood sugar can damage their gut through a high sugar diet. Further, those with existing gut issues can develop high blood sugar. This message is not just for those with blood sugar problems or diabetes, it is for everyone who overindulges on processed carbs and added sugars. This season, as we prep for the holidays, keep tabs on your snacking habits and be kind to your body.