You’re in a dilemma.
You like bread, but on the other hand…
Everywhere you go, restaurants and grocery stores now offer gluten-free foods.
You spend a few minutes surfing online and discover a long list of reasons you absolutely must avoid gluten:
- It’s a toxin.
- It causes inflammation.
- It gives you autoimmune diseases.
- It gives you headaches, joint pain, and brain fog.
- It makes you fat and sick.
You’re confused. You’re wondering if your love of bread is worth the risk. You also want to know if giving up gluten is worth the trouble and expense.
This article will help you decide what the science says about whether or not you should go gluten-free. Before we start, here’s a quick primer on gluten:
What is Gluten, and Why is it In My Food?
Gluten is a combination of proteins found in most grains, such as wheat, barley, and rye. Gluten traps water and air in a foam as bread rises, which gives it a chewy, soft, moist texture.
Wheat is the most common source of gluten for most people. However, gluten is also used as a filler in many processed/prepackaged foods, like ketchup and salad dressing. Unless you’ve been actively trying to avoid gluten, you’ve probably been eating it almost every day. Some people think that’s a bad idea.
Why People Think Gluten Is Bad for You
Most of the arguments against gluten can be traced back to the idea that it increases intestinal permeability or gives you a “leaky gut.”1-5 In a nutshell:
- Gluten enters your small intestine.
- The gluten molecules irritate and attack your epithelial cells (the ones on the inside of your small intestines).
- This irritation causes your tight junctions — the space between your intestinal cells — to widen. In some cases, gluten also directly attacks your cells.
- Gluten, bacteria, and undigested food particles sneak through these gaps between your cells and into your bloodstream.
- Once gluten and friends enter your bloodstream, your body mounts an inflammatory response.
- This inflammation spreads throughout your body, wreaking havoc on your health.
Theoretically, if you eat gluten on a regular basis, your gut and body stay inflamed, and you develop an increased risk of the following (just to name a few):
- Autoimmune diseases like arthritis, M.S., autoimmune thyroid disease, etc.
- Long-term gut damage, which can lead to nutrient deficiencies.
- Diarrhea, constipation, bloating, and other digestive issues like irritable bowel syndrome (IBS).
- Inflammatory bowel diseases like Crohn’s disease and ulcerative colitis.
- Insulin and leptin resistance.
- Weight gain.
- Nerve damage (neuropathy) and neurological diseases like autism.
- Brain fog and headaches.
- Joint pain.
- Slow recovery from workouts.
- Heart disease.
We won’t get into detail on every single one of these problems, because research hasn’t examined how gluten affects most of these conditions directly.
Instead, let’s look at the people who probably do need to avoid gluten — based on the best available data — and see how likely it is that you’re one of them.
The Only 3 Science-Backed Reasons for Some People to Avoid Gluten
There are three conditions where people generally need to be on a gluten-free diet:6-11
- Celiac disease.
- Wheat allergy.
- Gluten sensitivity.
Let’s take a quick look at each.
1. Celiac Disease
Celiac disease (CD) is an autoimmune condition where the immune system attacks the lining of the small intestine in response to gluten.12-14
This intestinal damage prevents people with celiac disease from absorbing nutrients properly. This often causes nutrient deficiencies, short stature, low bone mineral density, weight loss, skin rashes, and neurological problems.12,15
In most cases, when people with celiac disease eat gluten, they get digestive problems like bloating, diarrhea, gas, and stomach pain. However, there are also many people with celiac disease who experience skin rashes and other more bizarre symptoms. Some never have symptoms of any kind.12
If you’ve been experiencing any of these symptoms, there are two blood tests you can take to see if you have celiac disease:
- Immunoglobulin A anti-tissue tranglutaminase (IgA-tTGA).
- Immunoglobulin A antiendomysial antibody (EMA).
If you test positive for one of these tests, there’s a 95% probability that you have celiac disease.12,16
These tests are generally confirmed by taking a few cells from your small intestine, and seeing how you respond to a strict gluten-free diet. There are cases where eliminating gluten doesn’t completely resolve celiac disease, but it’s considered the best available treatment.
About 0.7-1.2% of the population has celiac disease.9,16-18
If you haven’t been experiencing any of the aforementioned symptoms, most evidence indicates there’s no need to get tested.19,20
If you have some of the symptoms mentioned previously, and a negative blood test, it’s highly unlikely you have celiac disease.12
Now let’s take a look at another legitimate reason to avoid wheat.
2. Wheat Allergy
Some people are allergic to gluten, or other proteins found in wheat. Their immune systems overreact and release chemicals that cause:6,21
- Itchy dry skin.
- Burning eyes.
- Shortness of breath.
… and all of the other normal signs of an allergic reaction.
If you think you might have wheat or gluten allergy, there are three tests you can take:6,11,21,22
- IgE blood testing from your doctor.
- A skin prick test, where a small amount of a potential allergen is injected just beneath your skin.
- An oral food challenge, where you consume increasingly larger amounts of potential allergens.
You should do all of these tests with your doctor — self-experimentation won’t tell you for sure if you’re allergic to wheat.
Only about 0.4-0.5% of the population is allergic to wheat and/or gluten.23,24 If you haven’t been experiencing any of the symptoms listed above, it’s unlikely you’re allergic to wheat.
If you’re allergic to wheat, you don’t necessarily have to avoid it completely. People have varying degrees of wheat allergy. Some get symptoms after any exposure, while others can tolerate small amounts.25 Find what works for you.
Now let’s talk about the last (sort of) scientific reason you may need to avoid gluten.
3. Gluten Sensitivity
You don’t have celiac disease.
You’re not allergic to gluten or wheat.
But you’re still worried gluten might be bad for you.
It’s possible you may have non-celiac gluten sensitivity, aka gluten sensitivity or gluten intolerance.
Here’s the basic diagnosis of gluten intolerance: feeling sick after eating gluten without having celiac disease or wheat allergy. There’s still some debate as to whether or not gluten sensitivity even exists, but most evidence indicates it does.6,7,9-11,22,26-28
There are several other key differences between celiac disease and gluten sensitivity.6-11,22,26,27
People with gluten sensitivity have no gut damage, and no increase in intestinal permeability (“leaky gut”).29
This is important, because most of the theoretical arguments about why gluten is bad for you are based on the idea that it damages your gut and makes it “leaky” — even without other obvious symptoms like bloating, diarrhea, and abdominal pain. It doesn’t, even in people who feel sick after eating gluten.
People with gluten sensitivity tend to have a higher rate of other non-digestive symptoms, like headaches, brain fog, fatigue, numbness, and joint pain.6
If you aren’t suffering from any of these symptoms, you don’t have gluten sensitivity. If you are, you may still not need to avoid gluten.
Why You Probably Don’t Need to Avoid Gluten
The chances that you have any of these conditions are slim. Most evidence indicates that less than 10% of the population has celiac disease, wheat allergy, or gluten intolerance, and it may be less than that.9
If you aren’t experiencing any symptoms of these three conditions, there’s no sound scientific reason for you to avoid gluten. None.
Even if you think you have gluten sensitivity, it’s possible you’re wrong.
There’s no firm definition of what gluten sensitivity really is. There are no objective lab tests. This means people can self-diagnose themselves, which opens a Pandora’s box of logical fallacies.
If you’ve been experiencing unexplained headaches, tiredness, weight gain, brain fog, joint pain, and digestive problems, it’s tempting to blame it on one cause, like gluten sensitivity. (The “one true cause” fallacy). It’s more likely that your problems are caused by a number of other issues that have nothing to do with gluten, like lack of sleep or exercise, stress, excess weight, etc. (The “confusing correlation with causation” fallacy). You know, the simple stuff that’s also really hard to make yourself do.
It’s also possible that the reason so many people are interested in going gluten-free has nothing to do with feeling sick.
People do crazy stuff all of the time because they think it will make them healthier, stronger, faster or more attractive, and gluten-free diets are no different. (The “confirmation bias” fallacy).
Since gluten free diets are becoming so popular, more celebrities and athletes are also joining in, which reinforces the idea that gluten is bad for you. (The “appeal to anecdote” and “appeal to popularity” fallacies).
Do You Need to Go Gluten-Free?
Unless you have celiac disease, there’s no evidence eliminating gluten will protect you from any disease.
There is no evidence that having an allergy to wheat increases your risk of disease6 — it just makes you feel lousy.
There are probably some people who have a negative physiological reaction to gluten that isn’t explained by celiac disease or wheat allergy (gluten sensitivity). However, the number of people who think they’re gluten sensitive is probably far greater than the number that actually are.
The Bottom Line: If you don’t feel sick after eating gluten, there’s no reason to avoid it.
If there isn’t a problem, there isn’t a problem. So enjoy that bagel.
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Do you think gluten sensitivity is a problem for most people?
Do you think there are other reasons gluten is bad for you?
Do you have any other questions about gluten?
Share your thoughts and questions in the comments section below.
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