What Are Probiotics: Benefits, Risks, and Common Myths

Walk into any health store today, and you’ll see shelves full of products that claim to have probiotics — from yogurt and kombucha to supplements and even skincare. But what are probiotics really, and do they actually work? More importantly, are they the right choice for you?

Probiotics are live, “good” bacteria that can support your health when taken in the right amounts. They help keep your gut healthy, support your immune system, and can improve overall well-being. In recent years, probiotics have become very popular, and many people now take them daily as part of their health routine.

At Conscious Medicine in Alpharetta, we focus on gut health using a complete, science-based approach. While probiotics can be very helpful for many people, they’re not the same for everyone. It’s important to understand what they do, how they can help, and what risks or side effects they might have before deciding if they’re right for you.

This guide will explain what probiotics are, their proven health benefits, possible side effects, and common myths. Whether you’re new to probiotics or want to make the most of the ones you already take, this information will help you make smart, informed choices for your health.

What Exactly Are Probiotics?

Probiotics are live microorganisms—primarily bacteria and some yeasts—that provide health benefits when consumed in adequate amounts. The term “probiotic” comes from the Greek words “pro” (promoting) and “biotic” (life), literally meaning “for life.”

Understanding Your Gut Microbiome

To understand probiotics, it’s important to first know about the gut microbiome—a large and diverse community of tiny organisms that live inside your digestive system. Your gut houses trillions of these bacteria from thousands of different species. Together, they form a mini ecosystem that can weigh around 2–3 pounds and actually contains more microbial cells than human cells in your body.

The Gut Microbiome’s Role: These microorganisms aren’t just passive residents—they actively participate in digestion (breaking down food components your body can’t digest alone), vitamin production (synthesizing vitamins K and B vitamins), immune system regulation (training and supporting immune responses), protection against harmful pathogens (competing with disease-causing organisms), metabolism regulation (influencing how you process nutrients and store fat), and even mental health (producing neurotransmitters that affect mood and cognition through the gut-brain axis).

Balance is Key: A healthy gut microbiome maintains a delicate balance between beneficial and potentially harmful microorganisms. When this balance is disrupted—a condition called dysbiosis—it can lead to digestive problems, weakened immunity, inflammation, mood disorders, and increased susceptibility to infections.

Common Probiotic Strains

Not all probiotics are created equal. Different strains provide different benefits, and understanding these distinctions helps you choose the right probiotic for your needs.

Lactobacillus Species:
These “good bacteria” live in the gut, urinary, and genital systems.

• L. acidophilus: Aids digestion, prevents diarrhea, supports vaginal health, and helps with lactose intolerance.

• L. rhamnosus GG: Supports immunity, prevents antibiotic-related diarrhea, and may help with eczema and allergies.

• L. casei: Boosts immune health, supports digestion, and helps with lactose breakdown.

• L. plantarum: Fights harmful microbes, supports nutrient absorption, and may ease IBS symptoms.

Bifidobacterium Species:
Mainly found in the large intestine, especially important for gut and immune health.

• B. bifidum: Supports immunity, gut lining, and vitamin production; may reduce IBS symptoms.

• B. longum: Reduces inflammation, supports digestion, and may help with stress and cholesterol.

• B. infantis: Important for infants; supports immune growth and helps with allergies and eczema.

• B. lactis: Improves digestion, immunity, and lactose tolerance; may help reduce body fat.

Saccharomyces boulardii:
A beneficial yeast that prevents and treats diarrhea, supports gut health during antibiotics, and helps with inflammatory bowel issues.

Streptococcus thermophilus:
Common in yogurt; aids lactose digestion, supports immunity, and helps reduce lactose intolerance symptoms.

How Probiotics Work?

Probiotics support health through multiple mechanisms. They compete with harmful bacteria for space and nutrients in the gut, produce substances that inhibit pathogen growth (like lactic acid and bacteriocins), strengthen the intestinal barrier (preventing “leaky gut“), modulate immune responses (training the immune system to respond appropriately), produce beneficial compounds (short-chain fatty acids that nourish intestinal cells), aid in nutrient absorption and vitamin production, and influence the gut-brain axis (affecting mood, stress response, and cognitive function).

At Conscious Medicine, we recognize that probiotic supplementation is just one piece of the gut health puzzle. Our functional medicine approach considers your entire health picture, including diet, stress levels, sleep quality, medication use, and underlying health conditions, to create personalized recommendations that truly support your wellness.

What Benefits Do Probiotics Provide?

The scientific evidence supporting probiotic benefits continues to grow, with thousands of studies exploring their effects on various aspects of health. Let’s examine the most well-established benefits.

Digestive Health

Probiotics are perhaps best known for their digestive benefits, and this is where the evidence is strongest.

Diarrhea Prevention and Treatment: Probiotics have been extensively studied for various types of diarrhea. Antibiotic-associated diarrhea affects up to 30% of people taking antibiotics. Probiotics, particularly Lactobacillus rhamnosus GG and Saccharomyces boulardii, can reduce the risk by up to 60%. They work by replenishing beneficial bacteria killed by antibiotics and preventing opportunistic pathogens from taking over. Infectious diarrhea from viruses, bacteria, or parasites can be shortened by about one day with probiotic use. They’re particularly effective for rotavirus diarrhea in children. 

Irritable Bowel Syndrome (IBS): IBS affects 10-15% of adults worldwide, causing abdominal pain, bloating, gas, and altered bowel habits. Multiple studies show that certain probiotic strains can reduce IBS symptoms by 10-40%, particularly abdominal pain and bloating. Bifidobacterium infantis and combination products containing multiple strains show the most promise. However, responses vary significantly between individuals, and finding the right probiotic may require some trial and error.

Inflammatory Bowel Disease (IBD): While probiotics aren’t a cure for IBD (Crohn’s disease and ulcerative colitis), they may help manage symptoms and maintain remission. Ulcerative colitis patients may benefit from certain probiotic combinations, particularly E. coli Nissle 1917 and VSL#3 (a high-potency multi-strain probiotic). These can help maintain remission and reduce inflammation. Pouchitis (inflammation after surgical removal of the colon) responds particularly well to VSL#3, with studies showing significant reduction in recurrence rates.

Constipation: Certain probiotic strains, particularly Bifidobacterium lactis, can help increase bowel movement frequency, soften stools, reduce straining, and improve overall digestive comfort. They work by improving gut motility and water content in stools.

Lactose Intolerance: Many people with lactose intolerance find that probiotics help them digest dairy products more comfortably. Lactobacillus acidophilus and Streptococcus thermophilus produce lactase enzymes, which break down lactose. Regular probiotic use can reduce bloating, gas, and diarrhea associated with lactose consumption.

Immune System Support

Your gut houses approximately 70% of your immune system, so it’s no surprise that probiotics significantly influence immune function.

Enhanced Immune Response: Probiotics help train your immune system to distinguish between harmful pathogens and harmless substances, reduce excessive inflammatory responses, increase production of natural antibodies, enhance activity of immune cells like natural killer cells and T-cells, and support the production of immunoglobulin A (IgA), which protects mucosal surfaces.

Reduced Infection Risk: Regular probiotic use has been associated with reduced frequency and duration of respiratory infections (colds, flu), fewer sick days in children and adults, reduced risk of urinary tract infections (particularly in women), lower rates of vaginal infections (yeast infections and bacterial vaginosis), and decreased risk of certain gastrointestinal infections.

Allergy and Eczema Prevention: Some evidence suggests that probiotics, particularly when taken during pregnancy and early infancy, may reduce the risk of eczema in children by up to 20%, help manage existing eczema symptoms, potentially reduce allergic sensitization, and support immune system development in ways that may prevent allergies.

Mental Health and Cognitive Function

The gut-brain axis—the bidirectional communication between your gut and brain—means that gut health significantly influences mental health.

Mood and Anxiety: Emerging research shows that certain probiotic strains (sometimes called “psychobiotics”) may reduce symptoms of depression and anxiety, lower stress hormone (cortisol) levels, improve mood and emotional well-being, and enhance stress resilience. Lactobacillus helveticus and Bifidobacterium longum have shown particular promise in clinical studies.

Cognitive Function: Some studies suggest probiotics may improve memory and cognitive performance, reduce age-related cognitive decline, support brain health through anti-inflammatory effects, and enhance the production of neurotransmitters like serotonin and GABA.

Other Potential Benefits

Heart Health: Certain probiotics may help lower LDL (“bad”) cholesterol levels, reduce blood pressure slightly, decrease inflammation associated with heart disease, and improve overall cardiovascular health markers.

Weight Management: Some probiotic strains may support healthy weight management by influencing how your body stores fat, regulating appetite hormones, reducing inflammation associated with obesity, and improving insulin sensitivity. However, effects are modest and vary significantly between individuals.

Skin Health: Probiotics may benefit skin health by reducing inflammation associated with acne and rosacea, supporting skin barrier function, potentially improving eczema and psoriasis symptoms, and promoting overall skin health from the inside out.

Vaginal Health: Lactobacillus species naturally dominate healthy vaginal flora. Probiotic supplementation (oral or vaginal) may help prevent and treat bacterial vaginosis, reduce recurrent yeast infections, support vaginal pH balance, and promote overall vaginal health.

At Conscious Medicine, we use comprehensive testing to assess your gut health and determine whether probiotics might benefit you. Our functional medicine approach considers your unique microbiome, health history, and wellness goals to create personalized recommendations.

Risks and Side Effects of Probiotics

While probiotics are generally safe for most people, they’re not without potential risks and side effects. Understanding these helps you make informed decisions and know what to expect.

Common Side Effects

Digestive Discomfort: When you first start taking probiotics, you may experience temporary digestive symptoms as your gut adjusts to the new bacterial populations.

Do probiotics make you gassy? 

This is one of the most common questions people ask about probiotics, and the answer is: sometimes, yes—but usually temporarily. When you introduce new bacterial strains to your gut, they begin fermenting dietary fibers and producing gases as byproducts of their metabolism. This can lead to increased gas and bloating, particularly in the first few days to weeks of supplementation.

The good news is that this gas production typically decreases as your gut adjusts to the new probiotic strains. Most people find that any initial gassiness resolves within 1-2 weeks. If gas and bloating persist beyond this period or become severe, it may indicate that the particular probiotic strain or dose isn’t right for you, you’re taking too high a dose too quickly, you have an underlying condition like SIBO (small intestinal bacterial overgrowth) that probiotics may worsen, or you need a different probiotic formulation.

To minimize gas from probiotics: Start with a lower dose and gradually increase over several weeks, take probiotics with meals rather than on an empty stomach, choose high-quality probiotics with strains that have been studied for your specific needs, stay well-hydrated to support digestive function, and consider trying different strains if one causes persistent discomfort.

Other Common Digestive Side Effects: Mild bloating (feeling of fullness or abdominal distension), changes in bowel habits (temporary constipation or loose stools), mild abdominal cramping, and increased thirst. These symptoms are usually mild and resolve within a few weeks as your body adjusts.

Serious Risks (Rare but Important)

While serious complications from probiotics are rare, certain populations face higher risks and should exercise caution.

Infections: In very rare cases, probiotic bacteria can cause infections, particularly in people with severely compromised immune systems, critically ill patients in intensive care, people with central venous catheters or other indwelling medical devices, premature infants, and people with damaged intestinal barriers (severe inflammatory bowel disease, recent surgery).

Sepsis and Fungemia: Saccharomyces boulardii, while generally safe, has caused fungemia (fungal blood infection) in rare cases, particularly in critically ill patients with central lines. Lactobacillus and Bifidobacterium species have very rarely caused bacteremia (bacterial blood infection).

Small Intestinal Bacterial Overgrowth (SIBO): Some people with SIBO may find that probiotics worsen their symptoms. SIBO occurs when bacteria overgrow in the small intestine, where they shouldn’t be abundant. Adding more bacteria through probiotics can sometimes exacerbate this condition, leading to increased bloating, gas, abdominal pain, and diarrhea.

Antibiotic Resistance: There’s a theoretical concern that probiotic bacteria could transfer antibiotic resistance genes to harmful bacteria in the gut. While this hasn’t been demonstrated to be a significant problem with commercial probiotics, it remains an area of ongoing research and monitoring.

Who Should Be Cautious?

Certain populations should consult healthcare providers before taking probiotics:

• Immunocompromised Individuals: People with HIV/AIDS, cancer patients undergoing chemotherapy, organ transplant recipients taking immunosuppressive drugs, and those with primary immunodeficiency disorders should use probiotics only under medical supervision.
• Critically Ill Patients: Those in intensive care units, patients with severe acute pancreatitis, people with central venous catheters, and those recovering from major surgery should avoid probiotics unless specifically recommended by their healthcare team.
• Premature Infants: While some probiotics may benefit premature infants, they should only be given under strict medical supervision due to infection risk.
• People with Structural Heart Disease: Those with damaged heart valves or a history of endocarditis should consult their cardiologist before taking probiotics, as there’s a theoretical risk of bacterial endocarditis.
• Pregnant and Breastfeeding Women: While probiotics are generally considered safe during pregnancy and breastfeeding, it’s always best to consult with your healthcare provider before starting any new supplement.

Common Myths About Probiotics

The popularity of probiotics has led to numerous misconceptions. Let’s separate fact from fiction.

Myth 1: All Probiotics Are the Same

The Truth: This is perhaps the most pervasive and problematic myth. Probiotics are incredibly diverse, with different strains providing different benefits.

Why It Matters: Lactobacillus rhamnosus GG is excellent for preventing antibiotic-associated diarrhea but may not help with IBS. Bifidobacterium infantis shows strong evidence for IBS relief but may not be the best choice for immune support. Saccharomyces boulardii is ideal for traveler’s diarrhea, but won’t help with lactose intolerance.

The Bottom Line: Choose probiotics based on your specific health goals and look for products with strains that have been studied for your particular condition. Generic “probiotic” supplements without strain identification may not provide the benefits you’re seeking.

Myth 2: More CFUs (Colony Forming Units) Is Always Better

The Truth: CFU count (the number of live bacteria in a dose) isn’t the only factor that matters, and more isn’t necessarily better.

Why It Matters: Effectiveness depends on the specific strain (some strains are effective at lower doses), survival through stomach acid (quality matters more than quantity), ability to colonize the gut (even temporarily), and the specific health condition being addressed. Some effective probiotics contain 1-10 billion CFUs, while others require 50-100 billion CFUs or more. Taking excessively high doses can sometimes cause more side effects without additional benefits.

The Bottom Line: Look for products with CFU counts that match those used in clinical studies for your specific health concern. More isn’t always better—appropriate dosing is what matters.

Myth 3: Probiotics Can Replace a Healthy Diet

The Truth: Probiotics are supplements, not substitutes for a healthy diet rich in fiber, fruits, vegetables, and whole foods.

Why It Matters: Probiotics need fuel to thrive—this comes from dietary fiber and prebiotics (non-digestible food components that feed beneficial bacteria). A diet high in processed foods, sugar, and low in fiber creates an environment where even the best probiotics struggle to survive and provide benefits. Whole foods provide nutrients, antioxidants, and compounds that probiotics alone cannot supply.

The Bottom Line: Think of probiotics as one tool in your gut health toolkit, not a magic bullet. They work best when combined with a diet rich in fiber, fermented foods, fruits, vegetables, and whole grains while limiting processed foods, excess sugar, and artificial additives.

Myth 4: Probiotics Work Immediately

The Truth: While some people notice benefits within a few days, most need to take probiotics consistently for 2-4 weeks before experiencing significant improvements.

Why It Matters: Probiotics need time to colonize the gut (even temporarily), compete with existing bacteria, influence immune function, and produce beneficial metabolites. The gut microbiome is complex and doesn’t change overnight. Some conditions (like antibiotic-associated diarrhea prevention) may show faster results, while others (like IBS symptom relief) may take several weeks.

The Bottom Line: Give probiotics at least 4 weeks of consistent use before deciding whether they’re working for you. If you see no improvement after 8-12 weeks, you may need a different strain or formulation.

Myth 5: You Need to Take Probiotics Forever

The Truth: Probiotic needs vary by individual and situation. Some people benefit from continuous use, while others may only need them periodically.

Why It Matters: Most probiotic bacteria don’t permanently colonize your gut—they’re transient visitors that provide benefits while present. Once you stop taking them, their numbers decline within days to weeks. However, the benefits they provided (like improved gut barrier function or immune modulation) may persist longer.

When Continuous Use Makes Sense: During and after antibiotic treatment, for chronic conditions like IBS or IBD, if you have ongoing digestive issues, or if you notice symptoms return when you stop.

When Periodic Use May Be Sufficient: For general health maintenance, during periods of stress or travel, or seasonally for immune support.

The Bottom Line: Work with a healthcare provider to determine the best approach for your individual needs. Some people thrive with continuous probiotic use, while others do well with periodic supplementation.

Myth 6: Probiotic Foods Are Just as Good as Supplements

The Truth: Both probiotic foods and supplements have their place, but they’re not interchangeable.

Probiotic Foods (yogurt, kefir, sauerkraut, kimchi, kombucha): Provide beneficial bacteria along with nutrients, often contain diverse bacterial strains, support overall dietary quality, and are generally safe and well-tolerated. However, they have variable and often unknown CFU counts, may not contain therapeutic doses of specific strains, and bacterial content can vary significantly between batches.

Probiotic Supplements: Contain specific, studied strains at known doses, provide therapeutic amounts for specific conditions, and offer consistency and convenience. However, they lack the additional nutrients found in foods, can be expensive, and quality varies significantly between brands.

The Bottom Line: Ideally, include both probiotic-rich foods and targeted supplements in your gut health strategy. Foods provide a foundation of diverse beneficial bacteria and nutrients, while supplements offer therapeutic doses of specific strains for targeted health concerns.

Myth 7: Refrigerated Probiotics Are Always Better

The Truth: While some probiotic strains require refrigeration to maintain viability, many modern formulations are shelf-stable without sacrificing effectiveness.

Why It Matters: Refrigeration requirements depend on the specific strains used, the formulation and protective technologies employed, and the packaging (moisture-proof, light-proof). Many high-quality probiotics now use freeze-drying and protective coatings that allow room-temperature storage without losing potency.

The Bottom Line: Follow storage instructions on the product label. Refrigerated probiotics aren’t inherently better—what matters is that the product maintains its stated CFU count through the expiration date when stored as directed.

Myth 8: Probiotics Cure Everything

The Truth: While probiotics offer numerous health benefits, they’re not a panacea for all health problems.

What Probiotics Can Do: Support digestive health, enhance immune function, potentially improve mood and mental health, help maintain a healthy weight, and support overall wellness as part of a comprehensive health strategy.

What Probiotics Cannot Do: Cure serious diseases like cancer, diabetes, or heart disease, replace necessary medical treatments, compensate for poor diet and lifestyle choices, or work the same way for everyone.

The Bottom Line: Probiotics are valuable tools for supporting health, but they work best as part of a comprehensive approach that includes a healthy diet, regular exercise, stress management, adequate sleep, and appropriate medical care when needed.

At Conscious Medicine, we help you navigate the complex world of probiotics with evidence-based recommendations tailored to your unique health needs. Our functional medicine approach considers your entire health picture to determine whether probiotics are right for you and, if so, which strains and doses will be most beneficial.

How to Choose the Right Probiotic?

With countless probiotic products on the market, choosing the right one can be confusing. Here’s what to look for:

Identify Your Health Goals: Different strains address different concerns. For digestive health (diarrhea, IBS, constipation), look for Lactobacillus rhamnosus GG, Bifidobacterium infantis, Saccharomyces boulardii, or Bifidobacterium lactis. For immune support, consider Lactobacillus casei, Lactobacillus rhamnosus, or Bifidobacterium lactis. For mental health and stress, try Lactobacillus helveticus or Bifidobacterium longum. For antibiotic-associated diarrhea prevention, use Lactobacillus rhamnosus GG or Saccharomyces boulardii.

Look for Specific Strain Identification: Quality probiotics list not just the genus and species but also the specific strain (e.g., Lactobacillus rhamnosus GG, not just “Lactobacillus”). Strain-specific research is what validates probiotic benefits.

Check CFU Count: Look for products with CFU counts that match those used in clinical studies for your condition. General health maintenance typically requires 1-10 billion CFUs, specific digestive issues may need 10-20 billion CFUs, and therapeutic use for conditions like IBS or IBD may require 50-100 billion CFUs or more.

Verify Quality and Purity: Choose products from reputable manufacturers with third-party testing (look for USP, NSF, or ConsumerLab certifications), guaranteed potency through expiration date (not just at manufacture), proper packaging (moisture-proof, light-proof), and clear storage instructions.

Consider Delivery System: Look for enteric-coated capsules or delayed-release formulations that protect bacteria through stomach acid, microencapsulation technology that enhances survival, or formulations specifically designed to survive digestive transit.

Check for Prebiotics: Some products include prebiotics (fiber that feeds beneficial bacteria) along with probiotics, creating a “synbiotic” that may enhance effectiveness.

Read Reviews and Research: Look for products with clinical studies supporting their specific formulation, positive reviews from users with similar health concerns, and transparent information about strain selection and dosing.

At Conscious Medicine, we help you select probiotics based on comprehensive gut health testing, your specific health concerns and goals, your medical history and current medications, and evidence-based research on strain effectiveness. Our personalized approach ensures you’re taking probiotics that truly support your unique health needs.

Conclusion

Probiotics represent a powerful tool for supporting digestive health, immune function, and overall wellness—but they’re not a one-size-fits-all solution. Understanding what probiotics really are, their evidence-based benefits, potential risks, and the myths surrounding them empowers you to make informed decisions about your health.

Your Path to Optimal Gut Health

If you’re considering probiotics or want to optimize your current regimen, don’t navigate this complex landscape alone. At Conscious Medicine in Alpharetta, we specialize in comprehensive gut health assessment and personalized probiotic recommendations based on your unique needs.

What Sets Conscious Medicine Apart:

• Comprehensive Testing: We use advanced functional medicine testing to assess your gut microbiome, identify imbalances, evaluate digestive function, and determine whether probiotics are right for you.
• Personalized Recommendations: Based on your test results, health history, current symptoms, and wellness goals, we recommend specific probiotic strains and doses that address your unique needs.
• Whole-Person Approach: We don’t just recommend probiotics in isolation. Our functional medicine approach addresses diet, lifestyle, stress, sleep, and other factors that influence gut health.
• Evidence-Based Care: Our recommendations are based on the latest scientific research and clinical evidence, not marketing hype or trends.
• Ongoing Support: We monitor your progress, adjust recommendations as needed, and provide continued guidance throughout your gut health journey.
• Root Cause Focus: We identify and address the underlying factors contributing to gut imbalances, not just symptoms.

Take Control of Your Gut Health Today

Don’t let digestive issues, weakened immunity, or other health concerns hold you back from living your best life. Whether you’re dealing with chronic digestive problems, recovering from antibiotic treatment, looking to boost your immune system, or simply want to optimize your overall health, we’re here to help.

At Conscious Medicine, we’re committed to helping you achieve optimal gut health through personalized care that addresses root causes, evidence-based recommendations tailored to your unique needs, comprehensive support throughout your healing journey, and education that empowers you to make informed health decisions.

Contact us today and discover how the right probiotic strategy, combined with comprehensive functional medicine care, can transform your health and quality of life.

Medical Disclaimer: The information in this blog is for educational purposes only and is not intended to replace professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified healthcare provider with any questions you may have regarding probiotics or any medical condition. Never disregard professional medical advice or delay seeking it because of something you have read in this article.

FAQ’s

Are probiotics safe to take every day?

For most people, yes — probiotics are safe for daily use. However, those with weak immune systems or certain health conditions should talk to a doctor before starting them.

Can I get probiotics from food instead of supplements?

Yes! Foods like yogurt, kefir, kimchi, sauerkraut, kombucha, and miso naturally contain probiotics. Eating these regularly can support gut health naturally.

Do probiotics have side effects?

Some people may experience mild gas, bloating, or stomach discomfort when starting probiotics. These symptoms usually go away as your body adjusts.

What benefits and risks are there with probiotics?

Probiotics can support digestion, improve gut balance, boost immunity, and help reduce symptoms like bloating or irregular bowel movements. However, risks may include gas, bloating, mild stomach upset, and—in rare cases—issues for people with weakened immune systems. Always consult a healthcare provider if you have underlying health conditions.

Can probiotics cause nausea and dizziness?

Yes, probiotics can sometimes cause nausea, dizziness, or mild digestive discomfort—especially when first starting them. These symptoms usually improve as your body adjusts. If they persist or worsen, stop taking the probiotic and speak with a healthcare professional.