Feature image Can Probiotics Cause Constipation 5 Possible Side Effects of Probiotics

Can Probiotics Cause Constipation? 5 Possible Side Effects of Probiotics

Probiotics are living microorganisms, encompassing bacteria and yeasts that offer health advantages when ingested in significant quantities. They can be consumed either as supplements or obtained naturally through fermented foods such as yogurt, kefir, sauerkraut, kimchi, and kombucha.

The positive health impacts of probiotic supplements and foods have been extensively documented, encompassing a decreased risk of infections, enhanced digestion, and even a lowered risk of certain chronic diseases.

Despite the numerous health benefits associated with probiotic intake, it is essential to acknowledge potential side effects. The majority of these effects are minor and only impact a small portion of the population. However, individuals with serious illnesses or compromised immune systems may encounter more severe complications.

This article delves into a comprehensive examination of the prevalent side effects of probiotics and offers insights on minimizing their occurrence.

They May Cause Unpleasant Digestive Symptoms

They May Cause Unpleasant Digestive Symptoms

While the majority of individuals do not encounter side effects, the most frequently reported response to probiotic supplements containing bacteria is a temporary surge in gas and bloating.

Those opting for yeast-based probiotics might experience constipation and heightened.

The precise reason why some individuals undergo these side effects is not fully understood, but they typically diminish after a few weeks of consistency.

To minimize the likelihood of side effects, commence probiotic intake with a modest dosage and gradually escalate to the recommended amount over several weeks. This gradual approach aids in the body's adaptation to the probiotics.

Should gas, bloating, or any other side effects persist beyond a few weeks, discontinuing probiotic consumption and seeking advice from a healthcare professional is advisable.

Amines in Probiotics May Trigger Headaches

Amines in Probiotics May Trigger Headaches

Certain probiotic-rich foods, such as yogurt, sauerkraut, and kimchi, contain biogenic.

Biogenic amines are substances that emerge when protein-containing foods undergo aging or fermentation by bacteria.

Common amines present in probiotic-rich foods include histamine, tyramine, tryptamine, and phenylethylamine.

Amines have the potential to stimulate the central nervous system, influence blood flow, and may act as triggers for headaches in individuals sensitive to these substances.

A study revealed that adopting a low-histamine diet led to a reduction in headaches for 75% of participants. However, a review of 10 controlled studies did not find a significant impact of dietary amines on headaches.

Further research is required to ascertain whether amines can directly induce headaches or migraines in specific individuals.

Maintaining a food diary that includes any headache symptoms can help determine if fermented foods pose an issue for you.

If symptoms are triggered by probiotic-rich foods, opting for a probiotic supplement might be a more suitable alternative.

Some Strains Can Increase Histamine Levels

Some Strains Can Increase Histamine Levels

Certain bacterial strains found in probiotic supplements can generate histamine within the human digestive tract. Histamine is a molecule typically produced by the immune system in response to perceived threats.

Elevated histamine levels prompt blood vessels to dilate, increasing blood flow to the affected area. Additionally, vessels become more permeable, allowing immune cells easy access to combat potential pathogens. This process leads to redness and swelling in the affected area and can also induce allergy symptoms such as itching, watery eyes, a runny nose, or difficulty breathing.

Ordinarily, histamine produced in the digestive tract undergoes natural degradation by an enzyme called diamine oxidase (DAO). This enzyme prevents histamine levels from reaching a point where symptoms manifest.

However, individuals with histamine intolerance may struggle to break down histamine efficiently due to insufficient DAO production. In such cases, excess histamine is absorbed through the intestinal lining into the bloodstream, resulting in symptoms akin to an allergic reaction.

Those with histamine intolerance are advised to steer clear of foods containing excess histamine. While theoretically considering probiotic supplements without histamine-producing bacteria may be beneficial, there is currently no specific research in this area.

Notable histamine-producing probiotic strains include Lactobacillus buchneri, Lactobacillus helveticus, Lactobacillus hilgardii, and Streptococcus thermophilus.

Some Ingredients May Cause Adverse Reactions

Some Ingredients May Cause Adverse Reactions

Individuals with allergies or intolerances should carefully review the labels of probiotic supplements, as these products may contain ingredients that could trigger adverse reactions. For instance, some supplements may include allergens like dairy, egg, or soy. Those with corresponding allergies should avoid such ingredients to prevent allergic reactions, emphasizing the importance of thorough label reading.

For individuals with yeast allergies, it is advisable to avoid yeast-based probiotics and instead choose probiotics with a bacterial base.

Lactose, or milk sugar, is a common component in many probiotic supplements. While studies suggest that most individuals with lactose intolerance can tolerate up to 400 mg of lactose in medications or supplements, some cases of adverse effects related to probiotics have been reported. Due to the potential for unpleasant gas and bloating in a subset of people with lactose intolerance, opting for lactose-free probiotic products may be a prudent choice.

In addition to containing potent probiotics, some supplements also incorporate prebiotics – plant fibers indigestible by humans but consumed as food by bacteria. Common types include lactulose, inulin, and various oligosaccharides. When a supplement features both probiotic microorganisms and prebiotic fibers, it is referred to as a synbiotic. Some individuals may experience gas and bloating when consuming synbiotics. For those who encounter these side effects, selecting a supplement without prebiotics may be a suitable alternative.

They Can Increase Infection Risk for Some

They Can Increase Infection Risk for Some

Probiotics are generally considered safe for the vast majority of the population, but they may not be suitable for everyone.

In rare instances, the bacteria or yeasts present in probiotics can enter the bloodstream and lead to infections, particularly in susceptible individuals. Those at a higher risk for infection include individuals with suppressed immune systems, prolonged hospitalizations, venous catheters, or recent surgical procedures.

Despite these risks, the overall likelihood of developing an infection is very low, and clinical studies in the general population have not reported any serious infections. The estimated risk of infection is minimal, with approximately one in one million people taking Lactobacilli bacteria-based probiotics developing an infection, and even lower for yeast-based probiotics, with only about one in 5.6 million users getting infected.

In cases where infections do occur, they typically respond well to conventional antibiotics or antifungals. However, it's important to note that in rare instances, deaths have been reported.

Research also suggests that individuals with severe acute pancreatitis should avoid taking probiotics, as this may potentially increase the risk of death.


Probiotics are living microorganisms that offer health advantages when ingested in significant quantities. They can be obtained through supplements or naturally present in fermented foods.

For the majority of the population, probiotics are considered safe, although some individuals may experience side effects. The most common side effects include a temporary increase in gas, bloating, constipation, and thirst.

In certain cases, individuals may also have adverse reactions to ingredients in probiotic supplements or naturally occurring amines in probiotic foods. If such reactions occur, discontinuing the use of probiotics is recommended.

While the overall risk is low, individuals with compromised immune systems, prolonged hospitalizations, or recent surgeries may be at a rare risk of developing infections from probiotic bacteria. People with these conditions should carefully assess the risks and benefits before incorporating probiotics into their routine.

In general, probiotics can be a beneficial addition to most people's diet or supplement regimen, with relatively few and improbable side effects.

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