Do you wonder if you have a food intolerance or food sensitivities? Read this post to find out the exact steps to discover your own food intolerances, learn about tests, and what food intolerance symptoms look like.
Many people ask me about how to know if they have food intolerances, being that it’s the main topic of my blog. I talk here about my gluten and dairy intolerances and how I manage them, the things that I wish I’d known along the way, and some of the shortcuts that I wish I’d known when I was first starting out.
I know that when you’re not feeling your best and you just want answers, you may wonder if you have food intolerances or food sensitivities at all. Or if something else health-wise is going on with you.
So here in this blog post, I want to take some time to really dig in to the question of “Do I have food intolerances or food sensitivities?” and talk about the two very simple ways to find the answer for yourself.
Inside this post, we’re going to answer about a few different questions leading to the big question of “Do I have food intolerances?”:
- What are food sensitivities or food intolerances?
- What are the symptoms of food sensitivities or food intolerances?
- What’s the difference between food allergies and intolerances/sensitivities?
- Why does knowing what foods you’re intolerant to matter for your life and your health?
- What are the steps to identify your own food intolerances and food sensitivities?
First, let’s get started on the first question:
What are food sensitivities or food intolerances?
A food intolerance or food sensitivity is an immune system response in the body when a certain food is eaten. This response is known as an IgA or IgG antibody response, and is a delayed reaction to eating specific foods.
These foods trigger your body and produce antibodies in response to thinking that they are invaders in your system, instead of food. For example, when a cold or flu virus shows up in your body, your immune system starts to attack it, trying to fight it off.
This reaction is the same when you have food intolerances – your body sends off antibodies to protect you against these invading foods. Most of the time, we aren’t fully aware we even have food intolerances or sensitivities, but are well-versed in the symptoms they produce.
Now that you know what they are, let’s talk about how food intolerances show up in your daily health and life. What do they look like on the outside?
What are the symptoms of food sensitivities or food intolerances?
While symptoms of food intolerances vary from person to person, these are the most common ones. This is definitely not an exhaustive list – and you may experience one or all of them with any given food you’re intolerant to.
- Feeling tired, sluggish, lethargic
- Trouble concentrating and staying focused
- Headaches
- Unusual tingling sensations
- Joint pain
- Susceptibility to catching colds & viruses
- Trouble sleeping
- Bad breath
- Tonsil stones
- Unpleasant body odor
- Frequent gas, bloating or indigestion
- Allergies and/or food sensitivities
- Skin problems especially acne and eczema
- Constipation, diarrhea and other gastrointestinal upset
- Feeling depressed
- Anxiety and anxious feelings
- Irritability and crankiness
- Back pain
- Mood changes
- Hemorrhoids
- Sinus congestion
Click here for a full food intolerance symptoms chart.
Now you may be thinking, well if I have a gluten intolerance, dairy intolerance, or intolerance to any other food, isn’t that just the same as having a food allergy? Is it as severe as that? Let’s dive into that next.
What’s the difference between food allergies and intolerances/sensitivities?
While you might feel like it’s life or death dealing with your food intolerances, the truth is that it’s not so extreme. There’s a big difference between dealing with food intolerances or sensitivities and food allergies.
Food intolerances can make you feel completely unlike yourself, uncomfortable, and just plain gross if you’re eating foods regularly that trigger reactions. But these reactions come on over time, anywhere from a few minutes to 72 hours after eating the foods you’re intolerant to.
In contrast, food allergies trigger an IgE immune response in the body, bringing bigger, more dramatic symptoms, like immediate hives, throat swelling, coughing, wheezing, swelling, vomiting, and even anaphylaxis if not treated right away. Food allergies can be life threatening, whereas food intolerances are not.
Next, let’s talk about why it even matters if you have food intolerances. What are the larger implications of having a food intolerance – and what will happen if you don’t know about them in the short and long term?
Why does knowing what foods you’re intolerant to matter for your life and your health?
There are plenty of great reasons to understand what foods you’re intolerant to, but these four reasons feel the most important: relieving yourself of chronic inflammation, getting better sleep, easing thyroid condition symptoms, and halting any further damage from a “Leaky Gut.” Let’s talk more about each of these below.
Chronic inflammation
When you’re constantly eating foods that you’re intolerant to, you’re creating ongoing inflammation in your body, because your body is fighting itself to keep you healthy.
While inflammation can be a good thing when you’re fighting off infections, chronic low-lying inflammation is actually detrimental to your health. If your body is in high alert all the time, you can cause lasting damage to your heart, your brain, and even your gut (source.
Sleep
>When your gut is inflamed from eating foods you’re intolerant to, you’re less likely to sleep well. When you don’t sleep well, your body doesn’t have time to heal or digest properly, causing even more gut and health issues.
It’s a destructive cycle, but easy to break: cut out the foods you’re intolerant to out of your diet and you’ll reduce inflammation throughout your body, sleep better, and feel a whole lot better. More on that here.
Thyroid conditions
Ignoring food intolerances for a long period of time can create an immune response, like chronic inflammation. This chronic inflammation and immune reaction can move throughout your body and cause further damage, like in your thyroid and bring to light some thyroid conditions like hypothyroidism, Grave’s disease, or Hashimoto’s disease.
When you take your food intolerances head on, start avoiding some of the main food triggers (most often gluten and dairy), you’ll not only start to feel better from your thyroid condition, but you’ll be treating yourself at the source and may be able to avoid taking hormonal thyroid medications entirely. You can read more on the link between food and thyroid here.
Heal your “leaky gut” and stop developing more food intolerances
Leaky gut is simply another term for gut impermeability. In short form, this simply means that you have teeny tiny holes in your intestines, and the foods you’re eating find their way into your bloodstream.
Food particles being in the wrong place means that your antibodies are attacking them as invaders in the body, because they aren’t where they should be. This causes the low level inflammation, because your body’s working overtime to fight the foods that are in the wrong place.
When your body is chronically inflamed from eating foods you’re intolerant to, your immune system is working overtime. If you already have food intolerances from a “leaky gut”, this condition will continue to get worse until you start healing your gut through diet and lifestyle.
That means that if you’re intolerant to one or two foods now, you could potentially be adding more foods to that list over time if you ignore those food intolerances right now.
Alright, so now you know why it’s valuable to know about your food intolerances and how you can start feeling better now the next question is: Where do I start? How do I discover mine?
What are the steps to identify your own food intolerances and food sensitivities?
The #1 thing you should do before you start looking to identify your own food intolerances is to… commit to changing your life and health for the better.
Once you know what foods you’re intolerant and sensitive to, you won’t be able to unlearn this information, so get on board with making a change from the knowledge you gain and move forward to create a diet and lifestyle that supports you and allows you to feel your best.
With that in mind, there are two basic ways to learn about your food intolerances: the elimination diet and using a blood test kit. Let’s go into detail about each below.
Way #1. The Elimination Diet (aka “The Free Way”)
An elimination diet is simply taking a good look at what you’re eating, then systematically removing one food at a time and bringing it back into your diet to determine if you have any adverse reactions to that food.
There are many programs that suggest that you need to cut out all major food allergens at once then slowly add them back in to your diet – and let me tell you, it’s not necessary, and it’s freaking hard to follow through with (I only made it 5 days without all top 8 allergens, meat, nightshade vegetables, and citrus fruits before I couldn’t continue on).
An elimination diet is simple, because you can do it at home, on your own time, using your own food. For this discussion, the elimination diet is what I’m calling the “free” way to discover your food intolerances, because yeah, it’s free. And it works.
How To Do An Elimination Diet in 6 Easy Steps
The steps to conduct your own elimination diet are basic and straightforward. Here’s what you need to do:
1. Start keeping a food journal
You can start with a few days or a few weeks whatever really feels right to you. Just write down what you eat and when.
Then as you make your way through the day, if you notice any weird symptoms (like brain fog or headaches), you can write down when you start to feel them.
If you’re one for keeping track but know you wont stick with it without something tangible in front of you, check out this great food journal to help you along the way. Its thorough and you can keep this with you over this process to narrow down any patterns you find.
This isn’t AT ALL about judging your food choices. I know many people think that food journals are a way to make you super aware of what you’re eating and it brings up all kinds of shame but don’t do that.
Just write down what you eat and be honest about it. Your body will thank you later.
2. Look for patterns between symptoms and foods
Notice that you always get headaches after eating bread? Or find yourself constipated three days after having milk?
Look for any obvious patterns that emerge and take note. It might not be as obvious as you’d like it to be. And if it isn’t thats okay. Just keep tracking until you start to get an idea as to what foods are triggering your symptoms.
3. Choose one food to remove from your diet – and do it
Take a food out of your diet ONE at a time and see how you feel for about 2 weeks.
If that food is a culprit for some of your symptoms, you will probably start feeling better within a few days. You’ll want to keep it out of your diet for longer than just when you start feeling better though. Give it at least two weeks.
Only take one food out at a time otherwise you’re going to feel like crap, because not only will you feel totally deprived and like you cant eat ANYTHING, but it will help you tease out the specific foods that you have reactions to one at a time.
If you take five foods out all at once, you’ll never know which one made you feel bad and the other four could have stayed in your diet.
4. Bring the food back in gently
So you’ve had the food out of your diet for a few weeks if you’re feeling better, awesome! Thats crazy good news! If you’re not, well then you may have some more elimination tests to do.
This is the part thats not so fun. Thats because your body hasn’t had the food in two weeks and your reaction to it (if you have an intolerance) might come back in full force. You might have a super strong reaction and that sucks.
But! The bright side is that you’ll know exactly what one food is that you’re intolerant to and you can move forward without eating that food any longer.
Bring the food back into your diet gently if you’re testing gluten, start with one piece of bread for three days in a row then wait a week. Its important to not go crazy with the food once you bring it back, because you’re looking for all symptoms in its most extreme and most subtle forms.
5. Watch for your reactions
Wait a week after bringing the food back and tune in to your body. Bring the food journal back in so that you’re acutely aware of whats going on in how you feel.
Remember reactions of a food intolerance are not always just physical they can be mental (like brain fog) or emotional (like you feel like you’re becoming the Hulk) too.
6. Make your determination and repeat the process
By this point, you probably feel at least slightly confident as to whether or not you have an intolerance to a food or not. If you do, you’ll want to remove that food from your diet completely. If not, then reintroduce it back into your diet as you would normally. If you’re still having symptoms of food intolerance or reactions you just cant explain, repeat the process over again until you find the culprit.
Okay, now that you know the basics steps for how to conduct an elimination diet, let’s talk about the time investment for this option.
As for how long it takes, well, that can depend on how much time you want to keep a food out of your diet before bringing it back in to test your reactions. It also depends on how many different foods you test in and out of your diet.
If you only wind up testing gluten, dairy, eggs, tree nuts, peanuts, shellfish, fish, and soy (these are the top 8 most common allergens), it can take you a couple months overall. But it you want to go deeper if you aren’t seeing your symptoms dissipate with every food intolerance you discover, then you might want to try even more foods based on what’s coming up in your food journal.
The bottom line: doing your own research into your body’s food intolerances is simple to do at home and free using detailed food journaling and tracking. But it may take you a long time and effort to adjust and readjust your diet multiple times over.
The Blood Test Way aka “The Fast Way”
A blood food intolerance test is a super simple way to discover your food intolerances by taking a sample of your blood, then sending it off to a lab to assess your food intolerances. This test is based on the reactions to a set of potential food triggers, and you’ll find out which foods you may have a food intolerance to all at once.
Instead of working through them one at a time like you would with an elimination diet, you will have a comprehensive set of foods to use as a starting point to make informed decisions about how you change your diet moving forward.
The blood sample collected is tested among a set panel of potential food triggers (a standard panel is around 96 different foods).
This test will measure the IgG (autoimmune reaction) level in response to being exposed to each and every food in the panel. Once your results have been documented, you’re notified of which foods you’re intolerant to and you can make changes to your diet.
A note on the validity of blood tests for food intolerances
There has been some controversy among some health providers around the validity of food intolerance testing, stating that there really isn’t a true way to test for food intolerances.
I think that while there may be some truth that identifying food intolerances can be extremely difficult and isn’t just boiled down to a blood reaction, I think there can be some immense value in taking a blood test for further direction.
In my experience of feeling completely overwhelmed with what was going on in my body, I needed a little bit of guidance of where to start when it came to changing my diet. I had done elimination diets for months. I had tried cutting out foods and bringing them back in.
I had tried journaling and journaling about what I was eating, but I had no real reason for why I was breaking out in hives every day for 6 weeks. After taking a blood test, I learned that I was also intolerant to eggs, a food that I had never in my wildest dreams thought that I’d had reactions to.
When it comes to the validity of these tests, I think if you’re at the point of feeling overwhelmed with no direction on which way to go, taking a bit of a shortcut to discover which foods you could be really focusing in on taking out of your diet is worthwhile information.
Whether it’s 100% accurate or not seems like less of a priority to me than figuring out what actions I can take to start feeling better as quickly as possible. Any small step to get me closer to that is valuable.
What food intolerance blood test should you use?
While there are a few different food intolerance and food sensitivity test kits available on the market, EverlyWell is my top choice for an at-home test kit. This food intolerance test kit is super simple, you can do it at home, and all you need is blood spot sample that you can easily (and painlessly) get on your own.
I am an affiliate for this product, so if you use my link, I will receive a small commission for the sale of the product – don’t worry this comes at no additional cost to you.
And from now until November 23, you can get 25% off your Everlywell Test using the code “THANKS25” at checkout. Don’t miss out on the chance for this major savings!
How To Complete the EverlyWell Food Sensitivity Test Kit in 6 Easy Steps
How to Complete an EverlyWell Food Sensitivity Test
Find out if you have food intolerances by completing an EverlyWell food sensitivity test kit. Follow these step-by-step instructions and get your results back in just a few days.
Materials
Tools
- Sample card
- Lancet
- Band Aids
Instructions
- Order the food sensitivity test from EverlyWell test and be sure to use the code EVERLY to save 12% on your order! Get it delivered right to your doorstep (I got mine in just 2 days).
- Register your test kit online following the directions inside the box.
- Collect your blood spot sample. Wash your hands, then follow the directions on the card for how to collect your blood spot sample. You’ll need to prick your finger using the device provided, then squeeze blood onto 3 of the 5 sample circles on the card provided.
- Secure your sample inside the plastic bag provided, then place into the mailer provided to mail back to the certified lab. No worries, the return shipping is pre-paid and included.
- Within 5 days, you’ll receive your results on the EverlyWell secure platform, where you’ll be able to see all the foods from the 96 food panel that you are reactive to. You can review your results, see the level of reactivity to each food, and get some tips for how to take action on this new knowledge about your health.
- Take informed action. Now that you have the results of your food intolerances via a blood test kit, you can make some decisions as to how you will change your diet.
Notes
If you decide to use my link for EverlyWell, I’ll share with you a bonus guidebook that I’ve put together just for those of you who purchase this kit on my recommendation. The guidebook is called "Navigating your Food Sensitivities" and inside you’ll get my top 5 tips what to do AFTER you get your test results back from EverlyWell. Just send me a screenshot of your receipt of your receipt and I’ll send it over to you.
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I hope that you’ve found this blog post valuable and informative as you’re uncovering questions about your own health journey.
Remember, there’s no right or wrong way as to how you go about figuring out if you have food intolerances – and there’s nothing wrong with you if you do or don’t have them. I wish you loads of insight and clarity on your journey ahead.
Ready for the rest of this series? Be sure to check out my posts about food intolerances!
Learn more about food intolerances and how to navigate them with these posts.
What is a food intolerance?
What is a food intolerance? What’s the definition of a food intolerance? What are some food intolerance examples? What are some common food intolerances?
21 Food Intolerance Symptoms That May Surprise You
Have you ever wondered what food intolerance symptoms are? Knowing these can help you determine if you need to conduct an elimination diet, if you are lactose or dairy intolerant or maybe should consider a gluten-free diet.
4 Shocking Ways Food Intolerances Are Damaging Your Health
Have you wondered if you have food intolerances, but don’t understand what all the talk is about? Learn the four shocking ways unknown food intolerances are damaging your health in the short – and long-term – and what you should do to right away to start feeling your best.
How To Do An Elimination Diet in Six Easy Steps
Want to know how to do an elimination diet in just six easy steps? Learn how to discover food intolerances using an elimination diet.
8 Things You Need to Know about Food Intolerances & Food Sensitivity Testing
Curious about food intolerances and food sensitivity testing? Learn the 8 things you need to know before you get started.
Is food sensitivity testing right for me?
Is food sensitivity testing right for me? Find out how to choose a test that’s right for you, if you should see a doctor for food intolerance testing, and if you can conduct a food sensitivity test at home.
How to complete a food sensitivity test kit at home
Find out the six steps of how to complete a food sensitivity test by EverlyWell at home.
Linda Clark says
I have had hair sample intolerance testing.
Do you recommend them, thanks Linda
Great information thank you
Rachael Roehmholdt says
Hi Linda,
I’ve written about this in depth in a few other blog posts you might find useful:
https://www.rachaelroehmholdt.com/8-things-you-need-to-know-about-food-intolerances-food-sensitivity-testing/
https://www.rachaelroehmholdt.com/is-food-sensitivity-testing-right-for-me/
My big thought around food intolerance testing of any type is to use them as jumping off points to narrow down the potential foods you may be intolerant to, then do an elimination diet with the foods that have shown up on them. Any test you do might not be completely accurate, so you’ll want to test that food in and out of your diet to see if it makes a difference for you and the symptoms you’re experiencing. I hope that helps!