Signs and Symptoms of Parasites in Humans

Symptoms of parasites can arrive in humans after eating undercooked meat or touching pets.

illustration of candida, a possible parasite

The most noticeable symptoms of candida are chronic inflammation, chronic fever, and food allergies.

Kateryna Kon | Dreamstime.com

Microorganisms feeding on our bodies outnumber our cells by 10 to 1. A typical person carries as many as six pounds of microbes, all living in a delicate, symbiotic balance amongst each other. These microbes can cause either a beneficial or a harmful effect. Most assuredly, an imbalanced overgrowth of any one species can lead to serious symptoms of parasites in the intestines.[1]

Intestinal Parasites in Humans

Aside from “normal” microorganisms within the body, a person can be exposed to pathogenic parasites from the outside environment. Eating undercooked meat and touching pets are the two most common ways of contracting these types of parasites. Because parasitic illness is so common, it is important to learn how to recognize the symptoms of parasites in humans in order to treat them quickly. The most common intestinal parasites include candida, giardia, hookworms, tapeworms, and pinworms. We will discuss two of these parasites here. 

Signs of Parasitic Worms in Humans

Hookworms are centimeter-sized worms that attach themselves to the interior walls of their hosts’ intestines. Once there, the worms grow and reproduce, stealing nutrients and preventing them from being absorbed into the cells of the host. Hookworm larva can penetrate the skin, and hookworm eggs can be ingested or inhaled. The most common sources of eggs and larva are animal feces and undercooked meat. Remember that pets lick and clean themselves with their tongues, which can cause hookworm larva and eggs to become attached to their fur. Petting, kissing, and smelling pets are common ways of contracting the parasite.

The following are symptoms of a hookworm infection:

  • Blood in stool
  • Blood in cough
  • Diarrhea
  • Gas and bloating
  • Nausea and vomiting
  • Pale skin
  • Loss of appetite[2]

Signs of Candida Overgrowth

Candida is a fungus that can reside in the urinary, genital, and digestive tracts. It is a normal human microorganism, but can cause damage and inflammation when allowed to grow in excess. A study from the University of Petermo in Italy found that candida species can grow uncontrollably in environments of high sucrose, glucose, and fructose.[3] The typical western diet abounds with simple refined sugars such as these. They are found at high concentrations in carbonated beverages and energy drinks, and in white breads, white pastas, and white rice. Furthermore, with the abundance of antibiotics prescribed in western medicine, the candida fungus can grow easily when other intestinal microbes (“good” bacteria) have been destroyed by these drugs.[4,5]

The most noticeable symptoms of candida are chronic inflammation, chronic fever, and food allergies. These symptoms are due to candida’s ability to destroy the intestinal lining of its host.[6] The fungus secretes alcohols and enzymes that destroy proteins and antibodies in host cells, allowing candida to enter the bloodstream and suppress the immune system.

As candida thrives on simple sugars, withdrawal symptoms may be experienced if you stop eating sugary foods during a candida overgrowth.[7] This occurs because the fungus absorbs sugar intake before it can reach your own cells. Body cells can then signal the brain that they require more sugar. As foods that are high in these refined sugars are universally bad for health, candida overgrowth can indirectly contribute to weight gain and other problems associated with a high sugar diet.

How to Naturally Eliminate Symptoms of Parasites

In order to deal with worm infestations, you must remove yourself from the sources of their eggs and larva. The best way to do this is to stop consuming meat. Even well-cooked meat products can still contain worm cysts and eggs. Also ensure that you clean your pets frequently, and always wash your hands after touching them in any way. To remove the parasites that are already in your system, consume wormwood, clove, and black walnut. Turmeric, ginger, and garlic also help to create an intestinal environment that is unsuited for microbial growth.[8] There are several homeopathic remedies for symptoms of parasites available online or at your local health food store that have a combination of these, or other, anti-parasite herbs. Be sure to follow the dosage instructions on the manufacturer’s label.

The easiest way to eliminate excess candida is to remove its food source.  Eliminating refined sugars and simple carbohydrate products (white bread, white pasta, and white rice) will cause the candida to quickly die off. Temporary, acute toxemia (called a “Herxheimer’s reaction”) often occurs when treating candida infections.. This means that you may initially have a low-grade fever, feel fatigued, sluggish or flu-like, but these symptoms only last a few days and are a sign that your efforts are successfully killing the candida yeast. Probiotics are also essential in controlling candida.[9] These beneficial microbes compete against candida cells, keeping them at a controlled, low population. Turmeric, ginger, oregano oil and garlic will also help to prevent candida overgrowth. To learn more about these anti-candida supplements, read our articles here:

Originally published in 2014, this post has been updated.


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UHN Staff

University Health News is produced by the award-winning editors and authors of Belvoir Media Group’s Health & Wellness Division. Headquartered in Norwalk, Conn., with editorial offices in Florida, Cleveland, Pittsburgh, … Read More

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