Probiotics are live microorganisms, commonly referred to as “friendly” or “good” bacteria that are believed to confer health benefits to the individual when consumed in adequate quantities.

They are sold in various forms, such as tablets, capsules, powders, and drinks, and marketed as dietary supplements or functional foods.

Despite their numerous health benefits, probiotics may not be suitable for everyone. Certain individuals may experience adverse effects, and therefore, they should avoid or limit their consumption of probiotics.

In this article, we explore specific groups that may need to steer clear of probiotics and the reasons why.

1. People with weakened immune systems

Individuals with weakened immune systems, due to conditions such as HIV/AIDS, cancer, or organ transplant, cannot mount a robust immune response against pathogens.

These individuals are at a higher risk of developing systemic infections as a result of consuming probiotics, which are live microorganisms that may cause opportunistic infections if consumed in sufficient quantities.

Probiotics can also interfere with the efficacy of immunosuppressive drugs, which are used to prevent organ rejection in transplant recipients or treat autoimmune conditions.

Immunosuppressive medication works by suppressing the immune system, and consuming probiotics may interfere with this process, leading to adverse outcomes. Therefore, individuals with weakened immune systems should avoid consuming probiotics unless directed otherwise by a healthcare professional.

2. Infants and young children

Probiotics are commonly promoted as beneficial for infants and young children, primarily to prevent or treat gastrointestinal infections.

However, there is limited evidence to support the safety and efficacy of probiotic use in this population, and some studies suggest that probiotics may even pose a risk.

Infants and young children have an immature immune system and are susceptible to infections, especially those caused by bacteria or viruses.

Therefore, giving probiotics to infants and young children may introduce new microorganisms into the gut and disturb the balance of the existing gut microbiota, leading to adverse outcomes such as allergic reactions, sepsis, or bloody diarrhea. Additionally, some probiotics contain allergens, such as milk protein or soy, which may trigger allergic reactions in susceptible individuals.

In some cases, probiotics have also been associated with the development of central venous catheter-associated infections in premature infants.

Therefore, infants and young children should not consume probiotics unless directed otherwise by a healthcare professional.

3. People with certain medical conditions

Individuals with certain medical conditions, such as inflammatory bowel disease (IBD), short bowel syndrome, or other chronic illnesses, should consult with a healthcare professional before consuming probiotics.

Probiotics may worsen the symptoms of these conditions, leading to diarrhea, abdominal pain, and bloating.

Additionally, some probiotics may contain high levels of histamine or tyramine, which can trigger migraines or allergic reactions in susceptible individuals.

Therefore, individuals with migraines or histamine intolerance should avoid consuming probiotics or choose low-histamine strains.

Finally, some probiotics may interfere with medications used to treat specific medical conditions, such as antibiotics or antifungal drugs.

Therefore, individuals taking these medications should consult with a healthcare professional before starting probiotics.

4. Pregnant or breastfeeding women

Pregnant or breastfeeding women should also consult with a healthcare professional before consuming probiotics.

While probiotics have been shown to be safe in pregnancy and lactation, there is limited evidence to support their efficacy in this population.

Additionally, probiotics may contain allergens or contaminants that can harm the fetus or infant.

Therefore, pregnant or breastfeeding women should choose probiotics that have been independently tested for purity and safety and avoid high-risk strains, such as Lactobacillus rhamnosus GG or Bifidobacterium bifidum.

5. People with allergies or intolerances

Probiotic supplements and functional foods may contain allergens or contaminants that can trigger allergic reactions or intolerances in susceptible individuals.

Some probiotics contain milk proteins, soy, or gluten, which can cause allergic reactions or digestive issues in individuals with a known allergy or intolerance.

Additionally, some probiotics contain histamine or tyramine, which can cause headaches or migraines in people with histamine intolerance.

Therefore, individuals with known allergies or intolerances should choose probiotics that are free from allergens or contaminants and consult with a healthcare professional before starting probiotics.

6. People with recurrent infections

While probiotics are commonly promoted as beneficial for preventing and treating infections, some studies suggest that probiotics may be less effective in individuals with recurrent infections or chronic conditions.

For example, probiotics have been shown to be less effective in preventing urinary tract infections in women with recurrent infections or in preventing upper respiratory tract infections in children with a history of recurrent infections.

Additionally, some probiotics may even worsen the symptoms of chronic infections, such as cystic fibrosis or chronic obstructive pulmonary disease (COPD).

Therefore, individuals with recurrent infections or chronic conditions should consult with a healthcare professional before consuming probiotics and choose strains that have been shown to be effective in their specific condition.

7. Athletes and sports enthusiasts

Athletes and sports enthusiasts have specific nutritional and performance needs and may be attracted to probiotics that claim to improve performance, reduce inflammation, or prevent infections.

However, there is limited evidence to support the efficacy of probiotics in this population, and some studies suggest that probiotics may even have adverse effects.

For example, some probiotics contain caffeine or other stimulants that can interfere with sleep or cause palpitations in susceptible individuals.

Additionally, probiotics may interfere with the absorption of nutrients and supplements that are commonly used by athletes and sports enthusiasts, such as protein, vitamin C, or iron.

Therefore, athletes and sports enthusiasts should consult with a healthcare professional or a sports nutritionist before consuming probiotics and choose strains that have been shown to be safe and effective in their specific sport or activity.

8. People undergoing surgery

Finally, people undergoing surgery should avoid consuming probiotics, especially within 2 weeks of the surgical intervention.

Probiotics may interfere with the efficacy of antibiotics or pain medication used during the surgery, leading to adverse outcomes, such as bleeding, infection, or organ damage.

Additionally, consuming probiotics may cause diarrhea or other digestive issues, which can worsen the recovery process after surgery.

Therefore, individuals undergoing surgery should avoid consuming probiotics unless directed otherwise by a healthcare professional.

Conclusion

Probiotics have numerous health benefits and are generally considered safe for most people. However, certain individuals may experience adverse effects, and therefore, they should avoid or limit their consumption of probiotics.

Individuals with weakened immune systems, infants and young children, people with certain medical conditions, pregnant or breastfeeding women, people with allergies or intolerances, people with recurrent infections, athletes and sports enthusiasts, and people undergoing surgery should consult with a healthcare professional before consuming probiotics and choose strains that have been shown to be safe and effective in their specific condition or situation.