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Are Probiotics Making You Feel Sick? (Updated 2021)

Are Probiotics Making You Sick


Probiotics are one of the most popular health categories for supporting immunity, digestion and mood. Scientific evidence shows probiotics may even have a positive effect on cognitive function. With all these great benefits, why do some people feel worse or even sick when taking a new probiotic? We will discuss this phenomenon and ways you can minimize potential discomfort.

Are Probiotics Causing Sickness (Microbiome)The Complexity of the Microbiome

Our microbiome is extremely complicated and diverse, containing over 100 trillion bacteria and comprises 70% of our immune system. It has a major impact on energy, metabolism, and our overall wellbeing. These trillions of bacteria coexist and interact within a diverse and intricate ecosystem of fungus, nutrients, minerals and complex chemical processes. Probiotic containing foods and supplements have become a staple in the diets of millions of individuals to help maintain the health of this complex ecosystem.

So, can probiotics actually make us sick?

It is possible for probiotics to stimulate a detox reaction that can lead to a litany of symptoms that can vary from mild to miserable. This occurs when probiotics rapidly starve out unwanted organisms, causing metabolic byproducts to be released into the body. For instance, dead yeast cells over time can release up to 80 different toxins including uric acid, ethanol, and acetaldehyde, a potent neurotoxin. If you have ever started taking a probiotic and felt exhausted, feverish, or had flu-like symptoms, it may be linked to this type of detox effect, also known as a Herxheimer reaction. The medical community is well aware of Herxheimer reactions when people are treated for serious illnesses, such as certain bacterial infections, other autoimmune conditions or even after heavy rounds of antibiotics.

Probiotic Detox Sickness

Am I taking the wrong probiotic?
Experiencing detox symptoms does not necessarily mean that you are taking a poor-quality product, and one could even argue that it’s an indication that the product is working. However, well-formulated products can be effective while also minimizing detox-related symptoms.

Things to keep in mind with probiotic supplements in particular is that a product containing dozens of different strains of bacteria or the highest CFU count is not always more effective and, in some cases, can have an adverse effect on efficacy. Common grocery store probiotics tend to simply be formulated to offer the most CFU activity for the most inexpensive price, so they appear appealing on a shelf, but with little to no thought into actual strain quality or make-up. Often labeled as containing tens of billions of CFUs per capsule at their time of manufacture, only a tiny fraction of the CFU activity typically survives the time on a shelf, let alone the digestive process or the intestinal environment.

Designing the ideal Probiotic

Syntol Prevent Probiotic DetoxCountless hours and careful consideration went into developing our best-selling probiotic formula Syntol. Syntol is a daily probiotic, but so much more, combining prebiotics as well as probiotic spores and enzymes. Probiotic spores or “seeds” are superior to typical probiotics, as they are not as susceptible to acidic digestion and are extremely shelf stable. Spores germinate in the intestinal tract, attaching to the intestinal wall and have much higher survivability than non-spores, quickly restoring intestinal balance. Syntol’s Acid Armor® delivery capsules further defend against acidic breakdown.

Syntol’s enzyme and probiotic blend was specifically designed to minimize probiotic detox. Specialized enzymes are added to breakdown the organisms responsible for toxins and the probiotics are carefully selected non-competitive strains that do not interfere with other strains in your microbiome. This unique formula helps to cleanse the digestive system while limiting the uncomfortable detox. Syntol’s unique ingredients help digest dead and decaying organisms away before they can release potential chemicals and toxins, which helps to limit potential symptoms or signs of detox.


Subject suffers from fatigue and digestive issues.* Headache & Insomnia.  


Subject indicated energy levels are at a ten year high and digestion returned to normal.*

What should I do if I still experience a detox?

  • Continue to take your probiotic supplement. Although uncomfortable, this period should pass in in no more than 7 days.
  • Cut your dose in half and/or take your probiotic every other day to lessen symptoms.
  • Take your probiotic with food. Probiotics are more effective when taken on an empty stomach, but while you aren’t feeling your best, take with food for 7 days. You can change to taking on an empty stomach after your body has adjusted.
  • Be aware that combining Syntol with other probiotics, antifungals, and/or herbal detox products can intensify any detox reaction.

For more information about the benefits of Syntol Click Here


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