Gut Bacteria and Diabetes: What Are the Effects?

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diabetes and gut

Type II diabetes is the most common diabetes in adults (over 90% of cases), and according to statistics from 2015 it affects approximately 30 million Americans, or 9.4% of the population. Every year, 1.5 million Americans are diagnosed with the disease, and diabetes is the seventh leading cause of death in the USA.

Years ago, type II diabetes was called “adult-onset diabetes,” but that term is no longer used because young children are now developing this condition, and it’s happening at an alarming pace.

Diabetes is a metabolic disorder where glucose (blood sugar) levels are elevated above normal. Most of the time people show little to no symptoms, but their glucose level is elevated. When symptoms do show up, they are typically the following:

  • Increased thirst (polydipsia)
  • Increased urination (polyuria)
  • Nighttime urination (nocturia)
  • Fatigue
  • Blurred vision
  • Weight loss
  • Frequent infections
  • Slow healing sores

Risk factors for type II diabetes include the following:

  • Lack of exercise
  • A diet high in sugar (and high fructose corn syrup!) and processed carbohydrates
  • Being overweight or obese
  • Fat distribution (increased belly fat)
  • Family history
  • Aging
  • Gestational diabetes
  • Pre-diabetes

As I mentioned earlier, you may not have any signs or symptoms and, therefore, not know that you have an issue with blood sugar regulation. Fortunately, there are many ways to diagnose diabetes through blood work.

If you go to your doctor, he or she will likely run a fasting glucose, Hemoglobin A1C (HgA1C), or glucose tolerance test. If any of these tests are elevated above certain levels, you may be diagnosed with diabetes. Levels to watch out for include:

  • Fasting plasma glucose level over 126 mg/dl
  • Hemoglobin A1C above 6.5%
  • Two-hour plasma glucose level over 200 mg/dl post oral glucose tolerance test

The Gut Connection to Diabetes

It may be obvious that the foods you eat can have a direct impact on your blood sugar. For example, I don’t recommend starting your morning off with the following:

  • A glass of orange juice
  • A bagel with jam, a donut, or coffee cake (these are all really desserts in disguise)

This meal will spike your blood sugar and likely cause you to reach for more sugar and carbohydrates later in the day. It’s a vicious cycle that becomes difficult to break. Over time your body becomes resistant to insulin, and glucose cannot enter your cells as efficiently as before. Thus, the need for more sugar and carbs to make you feel good!

Instead, I recommend preparing a breakfast like the following:

  • Two to three scrambled eggs cooked in one tsp coconut oil
  • Sauté 1/4 of an onion and two cups chopped Swiss chard in avocado oil or coconut oil
  • Half an avocado

This type of breakfast puts less strain on your pancreas to produce insulin and your blood glucose levels will be much lower compared to the orange juice and bagel breakfast. Plus, you will feel much more satiated and will likely feel better as the day progresses. That’s because your blood sugar will be stable, and you will not be dependent on more sugar and carbs to boost your energy or mood. 

What may not be so obvious is that the health of your microbiome can affect your metabolism and influence your blood sugar just as food does. In a 2015 article on diabetes and gut health from Gut Microbes, the authors state “unequivocal evidence demonstrates that gut microbes influence whole body metabolism by affecting the energy balance, gut permeability, metabolic endotoxemia, and inflammation that are associated with many metabolic disorders.” 

For example, some gut bacteria produce metabolites called short-chain fatty acids (SCFAs), which serve many functions in the body. In regard to blood sugar, SCFAs have been shown to affect the body’s ability at the intestinal level to produce glucose (gluconeogenesis) and can have a downstream affect on insulin release as well.

Ways to Improve Your Blood Sugar

At this point, I don’t think research has explained HOW to manipulate the gut microbiome so that blood sugar improves.  What we do know is that gut microbes do play a role in metabolism, which over time will be more fully understood.

You can help improve your blood sugar by experimenting with these simple food-related tips. They’ll likely improve your metabolism and blood sugar regulation by supporting the health and diversity of the gut microbiome. 

  • Say no to sugar and processed foods.

You may feel good temporarily with a sugar high, but long term these foods don’t serve you in any way. 

  • Incorporate more fruits and vegetables into your diet.

Fruits and vegetables are high in fiber, and fiber provides fuel for your gut bacteria to produce short-chain fatty acids (SCFAs), which do have an effect on metabolism. 

  • Make sure you consume an adequate amount of healthy fats and protein.

Doing this with each meal will help balance blood sugar levels.

  • Stop eating when you feel 80% full.

This may seem trivial but eating too much is all too common these days, and we’re finding more and more that calorie restriction is very beneficial for your gut and overall health!



Dr. Drew Sinatra

Meet Dr. Drew Sinatra

Dr. Drew Sinatra is a board-certified naturopathic doctor and self-described “health detective” with a passion for promoting natural healing, wellness, and improving quality of life by addressing the root cause of illness in patients of all ages. His vibrant practice focuses on treating the whole person (mind, body, and spirit) and finding missed connections between symptoms and health issues that are often overlooked by conventional medicine.

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