Have you ever had a bad restaurant experience, food poisoning incident or been troubled by traveller’s diarrhea?
If so, you may have picked up a Giardia infection.
Giardia lamblia is also known as Giardia duodenalis and Giardia intestinalis. It is one of the most commonly found parasites alongside H pylori.
I have seen several cases where my clients assumed they had H pylori, only to discover that they actually had Giardia when we ran comprehensive stool testing to determine the root cause of their symptoms.
You do not want to take any chances with Giardia. Recent research from Scandinavia confirmed that this parasite can cause fatigue, mood disturbances and digestive problems for up to three years after the initial infection.
Giardia was described as long ago as 1681. It is a microscopic protozoan parasite that is considered to be the most common cause of diarrhoeal disease worldwide. Giardia is the most frequently found parasite in the US.
Giardia gained notoriety because of its ability to cause diarrhoea, but it can also cause many other symptoms. Because the organisms attach to the intestinal lining, they can cause a blanketing effect where large areas of intestine are covered.
This leads to the inability to digest and absorb food properly, inevitably leading to malnutrition, even in people who are eating a healthy diet.
Here is a list of symptoms that can be caused by Giardia:
- Diarrhoea 90%
- Malaise / Fatigue 86%
- Flatulence 75%
- Foul-smelling, greasy stools 75%
- Abdominal cramps 71%
- Bloating 71%
- Nausea 69%
- Anorexia 66%
- Weight loss (average 4kg) 66%
- Vomiting 23%
- Fever 15%
- Constipation 13%
- Urticaria 10%
- Reactive arthritis Unknown percentage
Table adapted from Hill, 2001, in Principles & Practice of Clinical Parasitology, edited by Gillespie & Pearson).
Notice how Giardia can cause general symptoms of malaise, as well as seemingly unrelated symptoms such as nausea, urticaria (a skin condition), arthritis and anorexia. In my experience, any unwanted visitor to our digestive system – be it a parasite, fungus or bacteria – has the ability to cause pretty much any symptom you can think of.
It’s also important to note that the symptoms listed above are similar to those caused by other parasites & bacteria. Cryptosporidium, Blastocystis hominis, C. difficile, H. pylori, worm infections and many others are all capable of causing the above symptoms.
Because these infections require different antibiotic protocols and specific herbal cleanses, it is critical to run effective testing.
It is now known that Giardia can also infect the biliary tree and stomach. Some researchers have shown that when Giardia infects the stomach, H. pylori may also be present:
“There is frequent co-infection with Helicobacter pylori in gastric giardiasis”.
*Hill, 2001, in Principles & Practice of Clinical Parasitology, edited by Gillespie & Pearson, page 228.
This confirms what we, as natural health practitioners, have been observing for many years now: namely that if people have one infection, they probably have at least another one that doesn’t get diagnosed.
For example, if a person has heartburn, nausea and stomach pain, a doctor may test for H pylori but completely ignore the possibility that the patient may have a further parasite infection further down the digestive tract.
A large water-borne outbreak of giardasis, in Vail, Colorado, during the winter season of 1965/1966 brought Giardia wide recognition. Since that time, scientists have learned a significant amount about this parasite.
Giardia has a teardrop shape (below). As you can see from the image, it has four thin filaments protruding from its body. These structures are known as flagella and they help Giardia to move.
Giardia also has a disc that allows it to attach to the lining of the small intestine.
Unlike some other parasites, Giardia’s lifecycle is very simple. There are only two forms of the organism, active trophozoites and inactive cysts.
As Giardia passes through the small bowel to the colon, it encysts. The cysts are passed out in the stool and are picked up by humans or animals that eat or drink from contaminated sources.
When Giardia cysts are ingested, the cysts are exposed to stomach acid and digestive enzymes. This process is called excystation and results in Giardia becoming the active trophozoite form.
Giardia is usually transmitted through contaminated water. However person to person transmission and food contamination are also common. It is believed that in USA alone, around 4-7% of the population is infected and that there may be as many as 2.5 million new infections per year.
Summary of possible transmission routes:
- Contaminated water
- Person-to person in settings of poor hygiene
- Children in day care centres
- Sexually active gay males (or any partners engaging in oral/anal sex)
- Custodial institutions
- Contaminated food
Giardia occurs in both humans and animals, which allows for frequent contamination of surface water supplies. Beaver droppings, for example, can contaminate drinking water supplies (Giardia is sometimes referred to as “Beaver Fever”).
The cyst form of Giardia can survive for several weeks in fresh, cold water.
Indeed, it is actually quite common for hikers and outdoor enthusiasts to pick up Giardia from drinking water in mountainous regions such as Colorado. Like Cryptosporidium, Giardia cysts are highly resistant to chlorination, so contamination of municipal water supplies is relatively common.
Chronic Giardia Infections
Initially, Giardia tends to cause acute diarrhoea. Studies have shown that these acute infections can be severe enough to lead to hospitalisation. However, most doctors do not acknowledge that the infection can become chronic.
Because Giardia attaches to the wall of the intestine, it can cause damage to the delicate structures that help in the digestion and absorption of nutrients, known as the villi. This can make it hard for the digestive system to absorb fat, vitamins such as A, D, E, K and B12, protein, iron and lactose.
Cris, a personal trainer in London, approached me in 2007 because he had some vague digestive symptoms but he was also suffering with low libido and some fatigue. We ran an initial test that revealed H. pylori. Cris worked on a stomach cleanse to clear the H. pylori and his retest showed that he’d successfully eradicated it. His symptoms were all improving when one day, around 8 months later, he contacted me and advised that he had just experienced two days of diarrhoea and headaches. We ran a further test, which came back positive for Giardia. We then did a general parasite cleanse and his digestive system returned to normal.
A person who has vitamin A, B12, fat, protein and iron deficiency may develop symptoms consistent with those deficiencies. So even if there are only very mild digestive symptoms, fatigue, skin problems, neural problems and other symptoms can quickly develop simply because the Giardia prevents adequate nutrition reaching the body.
Scientists have also discovered that Giardia infection leads to lactose intolerance. Again, this is due to the parasites disrupting digestive function.
Lactose is the sugar that is present in cow’s milk and this is one of the reasons why I recommend that all cow’s milk products should be eliminated for 3-6 months in my nutrition programmes. In fact, Dr. David R. Hill recommends that:
“All patients should be instructed to avoid lactose-containing products, so that any recurrent diarrhoea will not be confused with relapse of infection”.
I have also found that avoiding gluten is of paramount importance and that if these simple nutritional strategies are not followed, the parasite cleanses do not work nearly as effectively.
Giardia and Children
Playing outdoors, having dirty hands, scratching around in the soil and being exposed to bacteria and parasites is all part of helping a child’s immune system develop. However, it does increase the risk of acquiring infections such as Giardia.
Children in developing countries are at extremely high risk of acquiring infections such as Giardia and Cryptosporidium and in some countries infection rates exceed 60%. In developed countries, children in day care centres are at particularly high risk of acquiring Giardia, with 20-50% children being affected. Although these children may not have symptoms, they can introduce Giardia to family members.
Failure to thrive in children is associated with Giardia, even if there are no obvious digestive symptoms. Because Giardia inhibits the absorption of nutrients, growth and development of infected children can easily be affected.
Learn More about Common Human Digestive Parasites
If you would like to learn more about Giardia or any of H pylori’s common cousins, please read my e-book:
What Your Doctor Didn’t Tell You About Parasites.
Get Yourself Tested
If you are concerned that you or a family member may have Giardia, please do not hesitate to contact us to order a.
Likewise, if you have experienced food poisoning or traveller’s diarrhoea and have developed chronic symptoms such as fatigue, irritable bowel syndrome (IBS), skin complaints, depression, brittle finger nails, etc., please check out our comprehensive stool testing services so that you can finally get to the root cause of your symptoms and treat them accordingly.
If you would like our help in any way, please do not hesitate to contact us at:
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