Parasites and Thyroid Health
Published December 15 2014
It’s quite common for people with thyroid and autoimmune thyroid conditions to have infections. There are bacterial infections such as H. Pylori, fungal infections such as Candida, and viral infections which include Epstein Barr and Cytomegalovirus. Some people also have parasitic infections, and this can potentially cause or contribute to their condition. In this article I’ll discuss some of the more common parasites people become infected with, some of the methods of testing for parasites, and natural treatment methods to help eradicate parasites.
Before I discuss some of the common parasites, you might be wondering what some of the symptoms of parasitic infections are. Many people assume that having a parasitic infection will always cause symptoms such as bloating, stomach pain, diarrhea, etc. Although sometimes people with parasitic infections will experience these symptoms, this isn’t the case with everyone. In fact, sometimes people can have parasites for months or years without experiencing gastrointestinal symptoms.
How do people become infected with parasites? There are numerous factors which can cause a parasitic infection. One cause is poor hygiene. Poor sanitation methods can lead to parasites in both the food and water, which can lead to such an infection. This is one of the main reasons why people commonly get infected by parasites when traveling to certain countries. Having a weakened immune system can make someone more susceptible to many different types of infections, and this includes parasitic infections.
Common Types Of Parasites:
There are two main classes of intestinal parasites, which include helminths and protozoa. Helminths are worms with many cells, and include tapeworms, pinworms, and roundworms (1). Adult helminths are unable to multiply in the human body. On the other hand, protozoa can multiply inside the human body, and the most common protozoa in the United States are giardia and cryptosporidium (1). Below I’m going to discuss some of the more common intestinal parasites, as well as a few other types of parasites.
Giardia lamblia. This is a parasite of the small intestine that causes extensive morbidity worldwide (2). It lives in soil, food, and water, and can cause giardiasis, which is an infection of the small intestine (3). You can become infected by coming into direct contact with someone who has giardiasis, or by drinking water from contaminated lakes or streams, or contaminated foods. The main symptom someone presents with is diarrhea, although other symptoms can include gas, bloating, headache, loss of appetite, low-grade fever, and weight loss (3).
Cryptosporidium. This is another type of protozoan parasite that can lead to gastroenteritis. Infection of this parasite leads to Cryptosporidium enteritis, which is an infection of the small intestine and usually causes diarrhea, although other symptoms can include abdominal cramping, malaise, weight loss, and nausea (4). Two common causes of this infection include drinking from contaminated public water supplies and swimming in contaminated pools and lakes (4).
Blastocystis hominis. Blastocystis hominis was once considered to be a member of normal intestinal flora, but in recent years it has been accepted as a very controversial pathogenic protozoan (5). One study showed that the frequency rate of intestinal symptoms was 88.4%, with abdominal pain being the most frequent symptom (76.9%), and diarrhea and distention followed at a rate of 50.0% and 32.6% (5). The mode of transmission isn’t completely understood, although a few sources show evidence that contaminated water might be a source of infection (6) (7).
Entamoeba histolytica. Entamoeba histolytica is a protozoan that can live in the large intestine without causing damage, although sometimes it invades the colon wall, causing colitis, acute dysentery, or chronic diarrhea (8). The infection associated with this parasite is amebiasis, and it’s responsible for an estimated 100,000 deaths annually, making it the second leading cause of death due to a protozoan parasite after Plasmodium (9). In addition to causing gastrointestinal symptoms, there can also be extraintestinal manifestations which include amebic liver abscess and other more rare manifestations such as pulmonary, cardiac, and brain involvement (10).
Plasmodium falciparum. This is the parasite associated with malaria, which remains a major cause of morbidity and mortality in the tropics (11). It is estimated that every year approximately one million people are killed by this parasite, as it can cause severe blood loss, and also can clog small blood vessels (12). This doesn’t fall under the same category of the other parasites I mentioned so far, but since it is responsible for so many fatalities I figured I’d mention it in this article.
Cyclospora ceyatanensis. This is a coccidian parasite and commonly causes mild to severe nausea, anorexia, abdominal cramping, and watery diarrhea. (13). People can become infected with Cyclospora by consuming food or water contaminated with this parasite (14).
Trichomonas vaginalis. Infection by this protozoan is the most prevalent curable sexually transmitted infection in the United States and worldwide (15). In the United States, an estimated 3.7 million people have the infection, but only about 30% develop any symptoms of trichomoniasis (16). Having trichomoniasis can make it feel unpleasant to have sex, and without treatment, the infection can last for months or even years (16).
Pinworms. Pinworms are the most common worm infection in the United States, and are most common in school-age children (17). Children become infected by unknowingly touching pinworm eggs and putting their fingers in their mouths, which leads to the eggs being swallowed, hatching in the small intestine, and maturing in the colon (17). Enterobius vermicularis is the name of the parasite (18). Intense anal itching around the anus is the most common symptom.
Tapeworm. Tapeworm causes an intestinal infection, and is caused by eating the raw or undercooked meat of infected animals, typically beef or pork (19). A tapeworm can grow to longer than 12 feet and can live for years (19). Some of the different tapeworm species include Taenia saginata (beef tapeworm), Taenia solium (pork tapeworm), and Taenia asiatica (Asian tapeworm) (20). Although someone with tapeworm might experience some abdominal symptoms, frequently there are no symptoms, as it’s usually detected in the stool when having a bowel movement.
What Is The Best Method Of Testing For Parasites?
It’s important to understand that no method is 100% accurate when it comes to detecting parasites. If I suspect parasites I usually recommend a stool panel, and many of the well known labs use something called DNA/PCR technology, which looks for the DNA of parasites. For more accurate results a minimum of three stool samples should be collected on separate days. However, it is important to remember that a negative test for parasites doesn’t completely rule out a parasitic infection.
In fact, some people reading this are familiar with the “SCD Lifestyle dudes” (www.scdlifestyle.com), as they put together an interesting article on stool testing. What they did was show some case studies involving clients who received two different types of stool panels. One of these was the Microbial Ecology Profile from Metametrix, which uses DNA/PCR technology (they used the Metametrix #2105, which is no longer available), and they also used the GI Pathogen Screen from BioHealth, which uses staining and antigen techniques. They showed how some people would test negative for parasites using the DNA/PCR testing, but would test positive for parasites using the staining and antigen techniques. And for other clients the opposite was true, as they would show up positive on the DNA/PCR testing but would test negative using the other method.
As a result, they recommend utilizing both types of stool testing. The problem is that purchasing one stool panel alone is quite expensive, and so ordering two panels would obviously be even more expensive. Plus, I’m sure there’s the possibility of someone having a parasitic infection yet testing negative using both types of technology. But of course using both types of stool testing techniques will increase the chances of detecting a parasitic infection. And even though this article is focusing on parasites, the same can be true with other types of infections, including yeast and bacteria. There isn’t a single testing method which is 100% accurate in confirming these infections. And so I agree that multiple testing methods is preferable, although some people won’t be able to afford multiple tests to confirm or rule out a parasitic, yeast, or bacterial infection.
Some medical doctors will recommend an endoscopy and/or colonoscopy if they suspect a parasitic infection. An endoscopy involves the insertion of a tube in the mouth in order to examine the intestine, while the colonoscopy involves a tube inserted in the rectum. Some parasitic infections can also be detected through the blood. Most of these will look for specific antibodies one will produce when someone has a parasitic infection, although a blood smear can diagnose certain parasitic infections such as filariasis, malaria, or babesiosis (21).
Conventional Treatment Methods For Parasites
Conventional medical treatment will vary depending on the type of infection, as well as the symptoms presented. For example, if someone has a parasitic infection but has mild symptoms or no symptoms, then no treatment might be given. On the other hand, medications might be given in some cases. For example, with cryptosporidium enteritis, drugs such as nitazoxanide, atovaquone, or paromomycin might be used. Trichomoniasis is usually eradicated by using antibiotics such as either metronidazole or tinidazole. Metronidazole is also commonly given for Amebiasis, although it’s usually followed by giving other medications such as paromomycin or diloxanide. Cyclospora infections are usually treated with trimethoprim-sulfamethoxazole. Praziquantal is commonly used to treat tapeworms.
Natural Treatment Methods For Parasites
Getting rid of parasites can be a challenge. Fortunately there are some natural treatment methods available to eradicate certain types of parasites. When dealing with harmful parasites, you not only want to do things to help eradicate them, but you also want to improve the patient’s digestive health and improve the health of their immune system. Since approximately 70% of the immune system is in the gut, improving the health of the gut will also improve the health of the immune system. Although conventional treatment methods might need to be considered in some cases of parasites, since many of these medications will disrupt the health of the gut flora I recommend trying a natural treatment approach if at all possible, and to resort to conventional treatment methods if the natural treatments are ineffective. However, keep in mind that some herbs used to eradicate parasites and other pathogens can also affect some of the beneficial flora.
Probiotics. There is evidence that taking probiotics can help to reduce the risks of infestation by specific parasites, or at the very least help to complement other anti-parasite treatments (22). For example, certain strains of L. reuteri and L. acidophilus might be beneficial for those infected with Cryptosporidium (23) (24). Saccharomyces boulardii might help in treating giardiasis (25).
Anti-parasitic herbs. The two most well-known herbs for eliminating parasites include wormwood leaf and black walnut hulls. When one of my patients has a parasitic infection I commonly recommend an herbal complex which includes these two herbs, along with a few other ingredients which can help with parasites. There are numerous studies which show that wormwood can help with parasites (26) (27) (28), although there isn’t much in the literature about the benefits of black walnut with regards to parasitic infections. Keep in mind that the lack of scientific studies doesn’t necessarily mean that it’s not effective in helping against intestinal parasites.
Stemona root (Bai Bu). I also couldn’t find anything in the literature related to Stemona root and parasites, although this is used in some anti-parasitic formulas to expel parasites. Apparently it can also help to rid the body of lice.
Clove bud essential oil (Syzygium aromaticum). Clove is an essential oil, and the main constituents of the essential oil are phenylpropanoids such as carvacrol, thymol, eugenol and cinnamaldehyde (29). Clove essential oil isn’t specific for parasites, as it also has antifungal and antiviral activity, and can even be used as an insect repellent (29). It helps to support healthy bowel function, possibly by producing regular peristaltic action.
Garlic. Most people reading this know that garlic has antimicrobial properties, but in addition to having antibacterial activity against gram-negative and gram positive bacteria, it also has antifungal and anti-parasitic activity (30). Another study showed that garlic may be useful as an alternative treatment against nematode parasites in animals and humans (31).
Other Anti-parasitic agents. Other agents which might be effective in eliminating parasites include thyme and Pau D’Arco. Although many healthcare professionals use these agents for parasites, as well as other types of infections, there isn’t a lot of research which supports their effectiveness for parasitic infections. I couldn’t find anything about Pau D’Arco in the literature with regards to parasitic infections, although I was able to find one journal article which showed that thyme can be effective against Trypanosoma cruzi (32), which is a protozoa.
Can Having Certain Parasitic Infections Be Beneficial To One’s Health?
The hygiene hypothesis proposes that the stimulation of the immune system by certain microbes offers protection from the development of inflammatory diseases, and therefore a reduced exposure to infectious agents might be the cause for the rise in allergic and autoimmune conditions (33). In other words, certain parasites might actually offer protection against the development of autoimmune conditions such as Hashimoto’s Thyroiditis and Graves’ Disease. As a result, some people feel that certain parasites shouldn’t be eradicated unless if someone is experiencing overt intestinal symptoms. It’s a challenging situation, as most of the patients I deal with have an active autoimmune condition, and so if someone tests positive for a parasitic infection on a stool panel I will almost always recommend a protocol to eradicate these parasites. But there are a few small studies which show evidence that parasitic infections might help to suppress the inflammatory process/autoimmune response in those people with multiple sclerosis (34), Crohn’s disease (35), and ulcerative colitis (36).
But how can certain parasites reduce inflammation and suppress the autoimmune component? Studies show that helminth parasites increase the number of regulatory T cells (37) (38). And these regulatory T cells (Tregs) help to prevent autoimmunity. I spoke about Tregs in an blog post entitled “Regulatory T Cells and Thyroid Autoimmunity“. In the post I discussed how certain nutrients such as vitamin D, vitamin A, omega 3 fatty acids, and probiotics can increase these types of cells. But helminth parasites also can increase the number of these cells. And if someone with an active autoimmune thyroid condition, or any other type of autoimmune condition is infected by this type of parasite, based on the research I provided earlier it can be challenging to determine whether or not to put the person on an anti-parasitic protocol.
In summary, some people with thyroid and autoimmune thyroid conditions have parasitic infections. Some of these parasites will cause numerous symptoms, but sometimes the person with a parasitic infection will remain asymptomatic. There are different methods of getting a parasitic infection, as many intestinal parasites are transmitted by drinking contaminated water and/or drinking contaminated foods. Some parasitic infections such as babesiosis are caused by a tick bite. The two main classes of intestinal parasites include helminths and protozoa, although there are other types of parasites as well. Two commonly used methods for testing for parasites include DNA/PCR technology, and staining/antigen techniques. Some of the natural treatments which can help with certain parasitic infections include probiotics, wormwood leaf, black walnut hulls, stemona root, clove, and garlic. It’s also important to realize that certain parasites might offer protective benefits against inflammation and autoimmunity, as helminth parasites can increase the number of regulatory T cells, which can help to reduce inflammation and prevent autoimmunity from developing.