If you’re a type 1 diabetic and are still eating as you did before your diagnosis and struggling with your daily blood sugar management in addition to possible gut disorders, this post was written specifically for you. This definitive guide to gluten will go over:
- What gluten is and the medical research behind why it’s considered such a highly inflammatory substance to consume
- Common side-effects of gluten and how they influence gut and immune dysfunction
- Gluten’s association with type 1 diabetes and impaired blood sugar stability
- Why some gluten-free diets may not work when others do (yes, there’s a difference!)
Ready to understand how gluten may negatively impact a type 1 diabetic? Let’s get this ball rolling!
What is Gluten?
Whenever this question is brought up, I always think of the Jimmy Kimmel bit they did on his show when they interviewed pedestrians who proudly stated they were eating gluten-free (1).
They were then asked if they actually knew what gluten was.
It was quite humorous to see those being interviewed lacking full awareness behind their actions and responses.
So, let me provide you with a cheat-post, just in case you’re ever in the same situation and need to know, at the very least, what gluten is and how it may wreak havoc on someone’s health, especially a type 1 diabetic’s.
Gluten Basics
Gluten is a complex mixture of storage proteins found in grains like wheat, barley, and rye.
Specifically, gluten makes up approximately 80% of the protein found in these grains.
Typical Uses for Gluten
Baking
- Extends shelf life in foods.
- Makes dough stronger, which provides a more stable and structured shape to foods, like bread and pasta.
- Increases water absorption, which makes food products soft.
Non-Baking
- Enhances batter to help conceal moisture, especially in frozen foods.
- Binding component in processed meats, i.e. pork, beef, chicken sausage; also commonly found in pizza toppings.
These gluten-contaminated foods, or what I refer to as glutenoids, are a common food staple in the Standard American Diet (SAD).
Ok, Great…So, Why Do Some People Bash Gluten?
It’s not uncommon to read about skeptics who play down the serious effects gluten may have on one’s health.
On the other side, it’s also not hard to find gluten-free zealots, either.
Let’s stick straight to the science and go over some of the potential physiological side effects the medical literature has found gluten may cause for those who are sensitive to its consumption.
Common Gluten Problems
I believe in order to better understand where the problems are, one must first know how things should be working in the first place.
During digestion, peptides are broken down into amino acids, absorbed mostly through the small intestine, then sent to the blood where it can then be distributed throughout the body to be used accordingly.
Common examples of peptide function in the body are for:
- stimulating melanin production (helps protect against sun damage)
- blood sugar regulation; insulin is a polypeptide (2)
- satiety signaling (makes you know when you are full from eating)
- other hormonal functions
The gluten peptides that usually pose the most problems are the ones that are not able to be digested in the body as easily.
There is no positive function for gluten in the body, either.
This can lead to multiple inflammatory physiological responses.
Gluten Trouble #1: Toxic Peptides
A popular gluten peptide that gets a lot of clinical attention and in the medical literature is called alpha gliadin (3).
This peptide contains 20+ amino acids that make up approximately 15 – 20% of the total flour protein in wheat.
Although there are gliadin peptides that are able to be digested normally, there are others that are not, which can cause immunogenic effects in those with celiac disease and non-celiac gluten sensitivity (NCGS).
The two most popular gliadin peptides of this non-digestible nature are the 25- and 33-amino acid sequences, also known as 25-mer and 33-mer.
The 25-mer is considered to be more of a toxic peptide.
Whereas the 33-mer is recognized as the most immunogenic gluten peptide variable, which is able to directly reduce gut integrity, endocrine cell signaling, and increase toxic endocrine effects (4, 5, 6).
The impact alpha gliadin can have on the body is a big reason why it’s one of two primary blood markers routinely screened when testing for celiac disease.
The other, more sensitive blood marker, is transglutaminase 2 (TG2).
Transglutaminases are structural gut enzymes that help with the formation of the gut barrier.
Food manufacturers use transglutaminases as “meat glue” to bind proteins in processed meats, as well.
There are quite a few other components of gluten that are able to alter gut, brain, and skin functions beyond just alpha gliadin and TG2, though.
This is important to know because if someone tests negative for celiac disease it doesn’t mean they’re in the clear with no ill effects from consuming glutenoids.
Especially if they’re a type 1 diabetic, as you’ll soon read!
Although there are hundreds of different immunogenic peptides found in gluten, not all of them share equal hostility towards a celiac or a NCGS patient.
However, many researchers do suggest splitting gluten peptides into two groups:
- Toxic
- Immunogenic
Both of these groups interact with each other increasing intestinal damage risk.
This encourages the risk of immune dysfunction, especially among non-celiac gluten sensitive patients, who have a significantly increased risk of also having leaky gut due to the adverse effects gluten may have on their gastrointestinal (GI) system (7).
But hang on there because toxic peptides aren’t the only guilty pleasure gluten may have on your body.
Gluten Trouble #2: Problematic Proteins
Gluten contains proteins and peptides that may heavily influence inflammation among the body’s cells.
Two such gluten proteins are known as prolamines and glutelins.
These two proteins are water-insoluble, which also contributes to the GI system’s failed attempts to completely digest them, especially in the celiac and NCGS patient population (8).
In fact, the term “gluten” is normally restricted to its direct connection to prolamins, which are the major storage proteins in most glutenoids.
Prolamins allow gluten to be stretched and pulled while still maintaining its structure.
This is one reason digestive enzymes may have trouble breaking gluten down completely.
Glutelins perform more of a maintenance role to ensure gluten’s elasticity and strength.
Prolamins are also rich in glutamines and prolines, which are two non-essential amino acids that also contribute to gluten being resistant to digestion (9).
There are different prolamins among barley, wheat and rye with the highest contents of proline and glutamine found among these three grains.
And the more proline and glutamine found in these prolamins, the more toxic they may present themselves among those with gluten sensitivity.
The lack of consistent digestibility among gluten peptides, in addition to their potential toxic and immunogenic effects on the human body, are just a few reasons that this “ingredient” is able to pose a host of health problems.
Especially to those who may not be seeing any improvement with their current type 1 diabetic management.
(If your eyebrow just raised, keep reading. This info gets “better”.)
When these gluten proteins and peptides are not digested, the body fights them with inflammation that may influence digestive issues and non-gut related symptoms.
Now that we know some of the problems associated with gluten consumption, let’s see how gluten may directly affect type 1 diabetics.
Why a Type 1 Diabetic May Want to Reconsider Eating Gluten
Well, there’s actually two reasons they should consider this.
- If the Immune System is Already Compromised, There’s a Strong Likelihood of a Gut Pathology Already Being Present (& Gluten Can Make This Worse!)
Remember that the gut has two primary functions:
- Nutrient absorption
- Gut barrier protection
When there is an imbalance between good and bad gut microbes, this gut dysbiosis presentation typically arises well before autoimmunity can be detected (10).
Our gut health barters with the immune system in order for both of them to function as optimally as possible.
70 – 80% of our immune cells reside in the gut, which makes this relationship vital to work as harmoniously as possible.
When the gut is compromised, there’s almost always immune dysregulation that is either a cause or effect result, thereafter.
And gluten can worsen gut dysbiosis by promoting further gut inflammation, altering gut microbe balance, and damaging the intestinal lining (11)!
This is why I believe ensuring a strong gut foundation is crucial for one to thrive, not just survive, with one’s diabetic health.
Due to autoimmunity already being present, let’s find out the further damage gluten can do to those diagnosed with these conditions, especially type 1 diabetics.
2. Elevated Zonulin is No Friend to a Type 1 Diabetic
Another reason gluten should be avoided by type 1 diabetics is that its consumption may have further enabled their T1D diagnosis and complications via a stomach protein called zonulin.
Elevated levels of this protein have been shown to strongly increase leaky gut (aka intestinal permeability; I’ll go over this in more detail in the next section) risk and has similar associations to type 1 diabetes development.
Let’s explore zonulin a bit more.
What Does Zonulin Do?
Zonulin is a protein that regulates the tight junctions along the intestinal walls of the GI system.
But what the heck does this actually mean?!
The right amount of zonulin enables this proper function. In addition, it stops the entry of bacteria, antigens, toxins, and other
pathogens while allowing proper nutrient absorption.
Research has shown a link between zonulin levels, inflammatory markers, and a variety of diseases, so we know that this connection to leaky gut shouldn’t be ignored.
The integrity of these tight junctions can directly influence:
- The absorption of nutrients, minerals and microbes that pass through the gut to be distributed throughout the body accordingly
- Intestinal barrier function, which prohibits pathogens and other foreign substances from entering and causing problems in the body
Irregularities to these tight junctions have been shown to alter gut function and increase autoimmune risk (12).
And guess what?
Gluten increases the odds of this occurring by upregulating zonulin levels in the body (13).
Recent observations also suggest that bacterial infections and gut dysbiosis have also been found to upregulate zonulin production, as well (14).
This combo of gluten and zonulin has been well documented to suggest its influence on autoimmunity, cancer, and (at the very least) chronic inflammation (15).
Remember, the one thing that every and any disease, illness, and sickness have in common is chronic inflammation (there are also three other factors: mitochondrial dysfunction, high cortisol, and unbalanced gut microbes, but these are a topic for another post!).
Gluten, Zonulin, Leaky Gut, & Type 1 Diabetes
Alessio Fasano is an Italian medical doctor who is world renown for his research on topics predominantly in autoimmunity but also in gluten and intestinal permeability.
Intestinal permeability, also known as leaky gut, is a condition that promotes gut barrier dysfunction in the GI system.
What essentially occurs with this gut disorder, as a result of the loosened tight junctions in the GI tract, is that pathogens are now allowed to cross through the gut and into the blood.
The response to these foreign invaders triggers our immune system and can cause multiple inflammatory reactions as a result.
The multiple antibodies produced by the immune system further enables a wide array of possible leaky gut symptoms.
These symptoms can range from cognitive, autoimmune, neurological, gastrointestinal, skin, hormonal and more!
In one study Fasano conducted, his findings demonstrate that leaky gut may be seen well before autoimmune diseasesbecome present (16).
This is the primary reason that he, other researchers, and practitioners (myself included) believe that gut dysfunction may not only influence certain conditions but are able to make them more difficult to manage, as well (17).
In 2000, Fasano discovered zonulin, which helped prove the concept of leaky gut.
He also found that zonluin levels may also be increased among healthy individuals, as well (18).
In case a type 1 diabetic has done everything their physician has told them to do but are still experiencing management issues, there’s a strong likelihood of gut dysfunction being present, which needs to be assessed then addressed.
The gut problem may not be of gluten origin, but these GI disorders can be very cunning and they know how to hide from conventional testing and treatments that would otherwise validate their presence.
For example, conventional standards for celiac disease testing only covers up to 4 gluten proteins (most of the time, only 2 are tested), meanwhile there are 30+ proteins that can still cause havoc due to gluten ingestion.
It wouldn’t hurt to at least eliminate gluten consumption for at least 30 days before reintroducing it to see the kind of impact it may have on one’s body or symptoms thereafter.
Medical Research on Gluten & Type 1 Diabetes
Dr. Fasano’s research on gluten and type 1 diabetes is quite interesting (19)!
Here’s a brief summary of this study that I believe every type 1 diabetic should be aware of what it suggests:
- The first antibodies to initiate type 1 diabetes development and allow the immune system to attack itself are the islet cell auto-antibodies (ICAs).
(FYI: auto-antibodies means immune system antibodies; it’s a bad thing to have because they enable the immune system to attack its host, i.e. you!)
For those of you who don’t know, islet cells are where insulin is produced in the pancreas, specifically in the pancreatic β-cells.
- In addition to ICAs, more than 90% of the studied T1Ds also had antibodies attacking insulin and other type-1-diabetes-triggering cells.
- These auto-antibodies can be used to identify patients at greater risk of developing type 1 diabetes due to them being present months to years prior to onset of symptoms; they can also be detected in the serum as early as 6 months of age among genetically susceptible patients.
- There were significant increases in lymphocytes and other helper T-cells when wheat protein was present among these type 1 diabetics.
Lymphocytes and helper T-cells are part of the immune system protocol that attacks foreign invaders in the body.
- Dietary gluten was shown to disrupt immune system communication throughout the body.
- Gluten has been suggested to play a significant role in the development of type 1 diabetes and celiac disease in its triggering of tight junction disruption via zonulin upregulation.
- Given the high rate of comorbidity (aka two or more diseases present in a patient at the same time) between type 1 diabetes and celiac disease, proper screening for either disease while the other is present is highly recommended.
To add to this, a remarkable study on rats found that when they were exposed to heavy doses of zonulin, researchers were able to diagnose them with type 1 diabetes within 30 days (20)!
Let’s take step back and appreciate what this rat model found, shall we?
A force so strong that it enabled type 1 diabetes development within a month?!
Yes, these are rats and not humans, but holy guacamole, this is an incredible finding!
Something worthy to note is that the upregulation of zonulin was quite high in the rat study, but the frequency of gluten consumption by many could be argued to be just as high within the Standard American Diet, as well.
Just something to think about.
The evidence remains consistent that increased zonulin levels appear before severe inflammation and possible type 1 diabetes (21).
And with gluten being a potent variable to influence zonulin levels to increase, add this to the list of reasons why type 1 diabetics (and anyone else with an autoimmune condition) may want to avoid its consumption.
Can Zonulin Affect Blood Glucose Levels?
I love how you’re thinking!
Yes, it may also further complicate blood sugar management.
One study looked at increased zonulin levels as a biomarker of leaky gut as it relates to non-diabetic pregnant women and those with gestational diabetes (22).
With zonulin above normal, what they found suggests increased:
- A1C levels
- Fasting blood glucose readings
- Body Mass Indexes (BMIs)
In addition, they propose that increased zonulin levels may also influence the pathogenesis of gestational diabetes.
In another study with Chinese type 2 diabetics, they found increased zonulin levels associated with higher insulin resistance and abnormal blood sugars (23).
And don’t forget, due to gut dysbiosis likely being present among type 1 diabetics, this imbalance of gut microbes may also influence blood sugar mismanagement, as well (24).
Increased zonulin levels may just complicate this further (another vicious circle!)!
So, what might a type 1 diabetic be able to do in response to this likely problem with gluten?
Do Gluten-Free Diets Work?
Gluten-Free Problems
There’s a saying that I love by Nobel Peace Prize-winner Dr. Albert Schweitzer:
Based on the simple wording of “Do gluten-free diets really work?” the direct response is “maybe.”
What I mean by this is that if a celiac, NCGS patient, or a cautious type 1 diabetic (who’s yet to be tested and confirmed of gluten intolerance or sensitivity) abundantly eats the likes of these kinds of foods:
- Gluten-free cookies
- Gluten-free cereals
- Gluten-free cupcakes
- Gluten-free chips
- Gluten-free processed foods
…then there’s a good chance that this particular gluten-free diet won’t help.
At. All.
Acellular Carbs
The reason for this is that many of these processed, gluten-free foods have ingredients that typically contain acellular carbohydrates, which are capable of having adverse effects on blood sugar management and gut health (25, 26).
Acellular carbs lack cell structure and contain a high level of carbohydrate density.
They are commonly found among gluten-free-floured foods, such as breads, cookies, cupcakes and bagels.
Myotoxins & Heavy Metals
Other contaminants that these gluten-free items may possess are myotoxins and heavy metals.
Myotoxins are a secondary metabolite of mold, which can have adverse effects on human health, such as gut and lung impairment (27).
Corn is a grain (not a vegetable) that has a high tendency to be infected with myotoxins, which is also a commonly used ingredient among gluten-free products (28, 29).
When it comes to heavy metal toxicity, the U.S. Food and Drug Administration (FDA) have known for years that due to frequent pollution, it’s not uncommon for heavy metals to be present in foods, cosmetics and dietary supplements (30).
Metals such as lead, arsenic, cadmium and mercury can have profound effects on the body, especially among children (31).
A couple of studies demonstrate an increase in mercury and arsenic exposure in gluten-free foods in which rice is the main ingredient (32, 33).
Rice is highly efficient in absorbing these two metals from the soil.
Typically, washing the rice helps to reduce these heavy metals from binding to it, but how many manufacturers do you think are taking this proactive approach with their bottom line?
In addition, “gluten-free” foods are usually synonymous with the “low-fat” craze in that it actually should read “Chemical Sh*t Storm of Ingredient-Fillers!”.
Whenever there’s a “low-fat“ or “gluten-free” or “sugar-free” or a “diet ______” anything in a processed food, it usually means the manufacturer has to make up for what’s not in the food anymore to either increase shelf-life and/or taste.
As a result, many of these gluten-free cheat-foods may need to be reconsidered, especially if poor diabetic symptoms continue with their consumption.
Gluten-Free Solutions
Now, if the gluten-free regiment one speaks of consists of consuming a predominant number of whole foods with plenty of diverse meats, omega-3-rich fish, vegetables and some fruits, then yes, I feel this would be a great place to start.
The simple and short reason for this is that humans haven’t evolved to consume grains/gluten, despite its convenience and cheap costs to produce them.
In addition, if you ask any farmer why they choose to feed their livestock grains, all of them will respond that it helps to fatten up their animals the quickest!
This elevated fat is now another inflammatory trigger that may also influence gut dysbiosis, among a host of other complications that many of these animals do unfortunately succumb to.
Can Gluten Cause Type 1 Diabetes in Children?
Recent research suggests the possible prevention of diabetes by eating a gluten-free diet given how vital a role gluten appears to be playing between type 1 and type 2 diabetes development (34).
A mouse study also demonstrates that among non-obese, diabetically susceptible (NOD) mice, a gluten-free diet compared to a gluten-eating regiment had a reduced incidence of type 1 diabetes from 64% to 15% (35).
Other studies have suggested similar results, as well (36, 37).
Gluten may influence the pathogenesis of type 1 diabetes during infancy.
Its potential role is further suggested in this other mouse study, which found that type 1 diabetes and insulitis (disease of the pancreas) were significantly reduced among non-diabetic mice when the maternal mice maintained an exclusive gluten-free diet throughout their pregnancy (38).
A 2018 study also suggests that pregnant mothers consuming the most gluten, compared to those eating the least, had double the risk of their offspring developing type 1 diabetes, as well (39).
Early introduction of gluten to infants is not without its potential side effects, either.
These studies propose that early introduction of gluten to infants prior to 3 months of age or later than 6 months have associations with autoantibody formation and incidence of type 1 diabetes development, as a result (40, 41).
In 2019, during the Annual Meeting of the European Association for the Study of Diabetes (EASD), there was a presentation that suggested a child’s gluten intake within their first 18 months was associated with a 46% increase risk of developing type 1 diabetes for every extra 10 g of gluten eaten per day (42).
Hopefully, the potential ramifications of gluten consumption are becoming clearer, especially among the type 1 diabetic population.
Let’s take a look at the medical research of recently diagnosed type 1 diabetics and their benefits on a gluten-free eating regimen.
Are There Any Gluten-Free Benefits During the Honeymoon Period?
For those of you who may not know, the “Honeymoon Period” of type 1 diabetes is the period directly after diagnosis when pancreatic beta cell recovery may still be restored so that the patient may not need to be insulin dependent moving forward with their treatment.
Typically, it can last anywhere from 1 – 12 months after type 1 diabetes is officially diagnosed.
There was a study performed in Denmark that observed a 6 year-old, type 1 diabetic (without celiac disease) who went on a gluten-free diet within 2-3 weeks of his diagnosis (43).
Upon diagnosis, his A1C was 10.4% (252 mg/dL or 14.0 mmol/L).
He adopted a gluten-free diet, without insulin therapy, and after just 8 weeks was able to attain stable 5.8 – 6.0% A1Cs (120 – 126 mg/dL or 6.67 – 7.0 mmol/L).
At 20 months, that patient still had no need for insulin for his treatment and continued to eat more nutrient-dense and low glycemic foods throughout his diet.
There was also a small pilot study done on 15 children who were recently diagnosed with type 1 diabetes, that had similar results (44).
After 12 months, the children had significantly lower A1Cs and approximately half of them were still in partial remission, meaning they were not expressing typical T1D symptoms.
Personally, if I knew then what I know now, I do truly believe I may have been able to prevent permanent destruction of my pancreatic beta cells immediately after my diagnosis.
Better to gain this information late than never, though, right?
Needless to say, gluten consumption among type 1 diabetics may have its short-term, tasteful “rewards,” but it’s not without its potential health consequences.
However, can type 1 diabetics just go gluten-free and call it a day to a “happily ever after” ending with no further issues affecting their health?
Not always.
Let’s elaborate as to why.
When Gluten Symptoms are Too Stubborn to Leave
We’ve learned that gluten can increase zonulin levels and as they rise, intestinal permeability risk goes up, as well.
And when leaky gut occurs, it often leads to gut distress, nutrient malabsorption, and/or immune dysfunction.
This is why testing for gluten sensitivity/allergies should be a routine course of action among those with an already established autoimmune condition(s) if not done so already.
This is extremely urgent to test among those who wish to continue eating glutenoids but want to know if consuming them may be more problematic than previously thought.
Associations between leaky gut and many other health conditions are gaining more traction with each passing year in the medical research.
Conditions such as infertility, hypothyroidism, neuropathies, irritable bowel syndrome, rheumatoid arthritis and of course, type 1 diabetes are just a few of a very long list of conditions that may be influenced by gluten (45, 46, 47, 48, 49, 50).
Yes, I’m serious when I tell you gut health is a very big deal.
Especially to a type 1 diabetic!
So, why doesn’t transitioning the diet to a predominantly gluten-free protocol have a 100% equal effect among everyone who does it?
Doesn’t eating gluten-free resolve leaky gut?
Not always.
You see, it appears that once gut damage has occurred, going gluten-free may stop the fire, but there’s still a catastrophe left behind that isn’t going to fix itself until treated appropriately.
We’ve gone over that leaky gut can play a significant role contributing to many health conditions.
The foundation of all this lies with gut barrier compromise, which may then alter immune function.
There are studies that show celiacs with increased mortality rates, despite going gluten-free, even for multiple years in some cases (51).
The explanation for this falls on when celiacs go gluten-free, do their zonulin levels actually drop?
If they do, this helps considerably with more positive results.
However, in some cases compared to non-celiacs, they’re still elevated to the point where their tight junctions remain improperly restored (52).
This, as we all know, may continue to be a problematic concern.
What needs to be done is to restore tight junction integrity along the intestinal walls to help minimize or eliminate any pathogens from entering and promoting any further gut complications.
Pretty simple notion, right?
But this can also be a tricky endeavor to pursue as treating gut disorders typically has a high reoccurrence rate if not done properly.
The reason for this frequency is that triggering lifestyles need to be reduced or eliminated in addition to proper treatment for certain gut conditions.
Everything a type 1 diabetic consumes is either promoting better disease management or inhibiting it.
If one already has autoimmunity, let alone type 1 diabetes, the benefits and risks of gluten should be strongly considered.
I appreciate your attention and hope you’re now empowered with more T1D and gluten knowledge!
I kindly request you forward this to another T1D who may be lost or confused with their blood sugar mismanagement.
Summary
- Gluten is a mixture of proteins found in grains, wheat, barley, and rye
- Gluten proteins commonly have trouble being digested, which can lead to a variety of inflammatory and negative immune reactions
- Many medical researchers suggest splitting gluten proteins into 1 of 2 groups:
- Toxic
- Immunogenic (meaning: producing an immune response)
- Particular gluten structures make it difficult for gluten to be broken down properly (this is a defense mechanism)
- Gluten has been shown to increase zonulin levels, which is a protein that helps to regulate the gut’s tight junctions that allow the right materials to pass through during digestion
- When zonulin increases, this also increases leaky gut risk because this allows too many things to pass through during digestion that normally wouldn’t
- Type 1 diabetes was induced in rats within 30 days by exposing them to heavy doses of zonulin – this is how big of a deal gluten can be, especially among type 1 diabetics
- As a result, increased zonulin levels by gluten consumption may increase
- A1C levels
- Fasting blood glucose readings
- Body mass index
- Gestational diabetes
- As a result, increased zonulin levels by gluten consumption may increase
- If doing gluten-free diet, it’s encouraged to eat as many whole foods as possible and to minimize packaged and processed “gluten-free” foods as they are commonly lacking nutrients your body can actually use
- Some research suggests that type 1 diabetes risk increases among children exposed to gluten
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