Do I have a food intolerance? 10 common signs to look out for

Do I have a food intolerance? 10 common signs to look out for

Written by: Boxie McGee
Medically reviewed by: Dr Gareth James MBBS, DRCOG, DFFP, MRCGP
To give you technically accurate, evidence-based information, content published on the Check My Body Health blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

In this article

Let’s face it - feeling “off” after eating has become the norm for many of us. From unexpected bloating to mysterious fatigue, these symptoms often go ignored or blamed on stress, hormones, or just getting older. But what if your body is actually trying to tell you something?

If you’re wondering, “Do I have a food intolerance?”, this blog will walk you through 10 of the most common food intolerance symptoms so you can stop guessing and start feeling better.


What is a food intolerance?

A food intolerance happens when your body has trouble processing certain foods, triggering an immune response. It’s different from a food allergy, which can be life-threatening and typically causes immediate reactions. Food intolerances are usually slower to appear and can affect your digestion, skin, energy levels, and more.


10 common signs of a food intolerance

1. Bloating after meals

One of the most common signs of intolerance is bloating - that puffy, uncomfortable feeling in your belly after eating. If this happens regularly (especially after dairy, gluten, or processed foods), it could be a red flag.

 

2. Frequent fatigue

If you feel constantly tired, even after a full night’s sleep, it might not just be burnout. Food intolerances can affect your energy levels and leave you feeling drained.

 

3. Headaches or migraines

Certain foods (like cheese, chocolate, or wine) can trigger headaches in sensitive individuals. If you’ve noticed a pattern, an intolerance could be the cause.

 

4. Digestive issues (gas, diarrhoea or constipation)

Gut trouble? Intolerances often lead to irregular bowel movements, excessive gas, or stomach cramps. These symptoms might flare up after specific meals or snacks.

 

5. Skin problems (acne, rashes, eczema)

Your skin reflects what’s happening inside your body. Unexplained breakouts, rashes, or flare-ups of eczema could be your body reacting to a food it doesn’t tolerate well.


6. Brain fog

Struggling to focus or feeling mentally “cloudy”? Certain food intolerances - especially gluten or dairy are known to impact mental clarity and concentration.


7. Mood swings or low mood

Your gut is closely linked to your brain. Intolerances that affect the gut may also impact mood leading to anxiety, irritability, or low mood after eating certain foods.


8. Joint pain or inflammation

Some intolerances (like gluten sensitivity) are known to trigger low-grade inflammation, which can show up as joint aches or stiffness.


9. Sinus issues or congestion

Constant congestion, a runny nose, or post-nasal drip (especially after meals) could indicate a sensitivity to dairy, gluten or other allergens.


10. Weight fluctuations or difficulty losing weight

Some food intolerances can disrupt your metabolism, leading to stubborn weight gain or water retention. Even if you're eating healthy, your body may be reacting negatively to certain ingredients.


So… do you have a food intolerance?

If any of these symptoms feel familiar, you’re not alone. Millions of people are walking around with undiagnosed food intolerances and it doesn’t have to be that way.

The good news? You can get answers. Our at-home Food Intolerance Tests make it easy to identify what’s causing your symptoms—no doctor’s appointment required.


Final thoughts

Understanding your body is the first step toward feeling better. If you’re experiencing multiple signs of food intolerance, now is the time to take control of your health. Don’t just put up with bloating, brain fog, or fatigue - get clarity, get tested, and get back to feeling like you again!


Ready to find out what your body’s trying to tell you?
Order your Food Intolerance Test today.



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