Parasite Testing | What You Need to Know (2024)

Parasites are living organisms that need a host (you!) to survive. While some of them don’t cause us any harm, many do. If you have IBS symptoms, you could have parasites living in your gut.

Read on to find out if a parasite test could reveal the reason behind your IBS symptoms.

Is there an at-home test for parasites?

There are many at-home tests for parasites.

Testing for parasites at home is very easy. Our Ultimate and Advanced Gut Health Tests both test for parasites.

What are the signs that you have a parasite?

There are many types of parasites, and they all produce different signs and symptoms in different people.

However, there are some common symptoms that many of them share. Here are ten of the most common symptoms of parasites [Source:]:

  1. diarrhoea
  2. skin bumps or rashes
  3. weight loss
  4. increased appetite
  5. abdominal pain and vomiting
  6. sleeping problems
  7. anaemia
  8. aches and pains
  9. allergies
  10. weakness

Can parasites cause IBS symptoms?

Parasites can, and do cause IBS symptoms [Source:].

If you have IBS symptoms, like diarrhoea, bloating and constipation, you could have a parasite. However, it’s equally likely that you don’t. There are many things that can cause IBS symptoms: a parasitic infection is just one of them.

That’s why a comprehensive stool analysis like a Healthpath Gut Health Test is a great idea: it gives you a window into the goings-on of your gut, and can reveal the root causes of your IBS symptoms.

Could you have a parasite? Test your gut health.

View our gut health tests

What else could be causing symptoms of parasites?

The symptoms of parasites are also the symptoms of many other conditions. In fact, all of the above symptoms can also be symptoms of IBS.

IBS is known as a ‘diagnosis of exclusion.’ That means that your doctor will diagnose you with IBS once they have ruled out other, more serious causes of your symptoms, like IBD (inflammatory bowel disease), cancer or gut infections.

So if you have a diagnosis of IBS, you need to dig deeper into your gut health to find out why you have symptoms like diarrhoea, bloating and constipation.

Some root causes of IBS symptoms are:


SIBO stands for small intestinal bacterial overgrowth. If you have SIBO, it means you have too many bacteria living in your small intestine, where numbers should be much lower than in your lower intestine, or colon. Upto 85% of people with IBS symptoms have SIBO [Source:].

Find out all you need to know about SIBO

Take an at-home SIBO test

Food intolerances

Food intolerances are different to food allergies. Food intolerances often happen as a result of an imbalance of the populations of microbes in your gut, known as dysbiosis [Source:].


Dysbiosis is an imbalance of the communities of microbes that live in your gut. Your gut includes both your small and large intestine. Countless studies have shown that dysbiosis is a significant root cause of IBS symptoms [Source:].

You can read more about dysbiosis in our blogs:

How long does it take to repopulate the gut with good bacteria?

How to get rid of bad bacteria in the gut

The good news is that with the right diet, targeted supplements, time and patience, you can rebuild your microbiome, tackle dysbiosis and find relief from your IBS symptoms.

Our Gut Health Tests reveal the types and levels of bacteria you have in your gut. You’ll also get information on:

  • your pH levels
  • your microbial diversity
  • your enterotype (which population your microbiome most closely matches)
  • your dysbiosis index (how balanced your microbiome is)
  • the presence of yeasts and moulds (including candida)
  • the presence of H. pylori and other pathogenic bacteria
  • your digestive function, immune system and levels of inflammation
  • evidence of leaky gut (a biomarker called zonulin measures intestinal permeability)


Stress affects your microbiome through the hormones your body releases when you’re in fight, flight or freeze mode [Source:]

People who have had a traumatic accident show a significant reduction in many types of bacteria in their gut microbiomes only 72 hours after their injury [Source:].

You can have many, or all of these root causes. Quite often, they are all driving each other in a vicious cycle.

Does the NHS test for parasites?

The NHS does test for parasites but the method they use is not very sensitive.

As far as we know, the NHS only uses microscopes to detect parasites, worms and their eggs in stool samples. While this method will pick up more severe infections, it can often result in false negatives (you get a negative result for parasites when you do actually have an infection) [Source:].

This method relies on the experience of the person behind the microscope. In other words, a more experienced lab technician is more likely to spot evidence of a parasite or worm infection than somebody who is relatively new on the job.

Worms and parasites can break apart easily, and sometimes stool samples will only contain fragments or sections of them. Those ‘pieces’ are a lot more difficult to spot than whole parasites or worms.

What’s the best way to test for parasites?

The best way to test for parasites is by PCR (polymerase chain reaction) technology.

The PCR method ‘looks for’ the DNA in parasites and worms. Because DNA is present in every cell of every organism, PCR technology can pick up an infection from any part of a parasite or worm, no matter how small.

One research paper [Source:] compared traditional microscopy testing for the parasite Giardia with PCR technology, and concluded that PCR technology should replace microscopy in all clinical settings for ‘all protozoans’ (parasites).

At Healthpath, we use PCR technology to test for six types of parasites.

Suspect a parasite? Try our advanced at-home test.

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What parasites do humans get?

Here’s a list of the most common parasites and worms found in humans:


Pathobionts (organisms that don’t always need to be eradicated):

  • Blastocystis hominis
  • Dientamoeba fragilis

Pathogens (organisms that do need to be eradicated):

  • Giardia lamblia
  • Entamoeba histolytica
  • Cryptosporidium spp.
  • Cyclospora cayetanensis

Helminths (worms)

All worms are pathogenic (potentially dangerous) and need to be treated. The most common are:

Taenia species (tapeworms)

  • Taenia solium
  • Taenia saginata

Ascaris species (roundworms)

Enterobius vermicularis (pinworms)

Ancylostoma species (hookworms)

  • Necator americanus (New World hookworm)
  • Ancylostoma duodenale (Old World hookworm)

Hymenolepsis species (dwarf tapeworm)

  • Hymenolepsis diminuta
  • Hymenolepsis nana

Trichuris trichiura (whipworm)

Strongyloides species (threadworm)

  • Strongyloides stercoralis

Microsporidia (fungal parasites)

  • Enterocytozoon species
  • Encephalitozoon species

Key takeaways

  • Parasites are one of many causes of IBS symptoms
  • To tackle your IBS symptoms, you need to find your root causes
  • The NHS do test for parasites, but they use a method that is likely to miss the signs an infection is present
  • Newer tests use the latest ‘PCR’ technology, which looks for the DNA of parasites and worms
  • A comprehensive stool analysis that uses PCR technology to detect parasites is more effective than traditional methods
  • If you have the symptoms of parasites, you need to take a deep dive into your gut health and explore all your possible root causes
  • Testing for parasites is just one necessary part of a wider investigation into the reasons behind your IBS symptoms


Alexandra Falconer MA (Dist) DipCNM mBANT is a Registered Nutritional Therapist specialising in IBS and related conditions. A graduate of Brighton’s College of Naturopathic Medicine, she is committed to fighting the root causes of chronic illness and bringing functional medicine to everyone who needs it.

Before her natural health career, Alex was a journalist and copywriter. She continues to write for magazines and media agencies, and now combines her two great passions—writing and health—by creating content that empowers people to claim their right to a healthy body and mind.

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