Introduction
Bloating after a routine weekday meal, unpredictable bowel habits, or that heavy, sluggish feeling in your abdomen can quickly drain your energy. In the UK, millions of people regularly experience unsettled digestion, often wondering whether an over-the-counter probiotic supplement or a pot of live yogurt could finally bring relief. Walk into any chemist or supermarket, and you will find shelves lined with capsules, powders, and fermented drinks, all promising to balance your microbiome.
However, the world of gut bacteria is complex. The human digestive tract is home to trillions of microorganisms, and simply taking a random probiotic off the shelf is rarely a magic bullet. Different bacterial strains perform distinctly different jobs in the body, meaning that what eases discomfort for one person may do very little for another.
This guide is designed for anyone looking to make sense of digestive health without the marketing hype. We will explore what probiotics actually are, which specific bacterial genera and strains have meaningful scientific backing, the role of fermented foods, and how to choose a supplement that fits your personal circumstances.
At Blue Horizon, we believe that sustainable health decisions come from understanding the whole picture rather than looking for a quick fix. If you are struggling with persistent digestive issues, our doctor-led approach follows three clear steps:
- Step 1: Consult your GP first. Always rule out clinical conditions, check for red-flag symptoms, and request routine medical investigations.
- Step 2: Carry out a structured self-check. Track your symptoms alongside daily habits such as fibre intake, sleep, hydration, and stress levels.
- Step 3: Consider targeted blood testing. If your symptoms remain unexplained, looking at broader markers—such as nutrient levels, systemic inflammation, or thyroid function—can provide a clearer clinical baseline for further conversations with your doctor.
Understanding the Gut Microbiome and Dysbiosis
To understand which probiotics are good for your digestive tract, it helps to first understand the environment they are entering. Our guide to what the gut microbiome is and why it matters provides further background on this complex ecosystem.
The gut microbiome consists of an intricate community of bacteria, yeasts, viruses, and other single-celled organisms residing primarily in your large intestine (colon). When this ecosystem is healthy and diverse, these microorganisms perform crucial biological functions:
- Digesting complex fibres: Breaking down tough plant carbohydrates that human digestive enzymes cannot process alone, producing short-chain fatty acids (SCFAs) like butyrate, acetate, and propionate.
- Strengthening the gut barrier: Supporting the integrity of the intestinal lining, which helps prevent unwanted substances from leaking into the bloodstream.
- Modulating the immune system: Roughly 70% of the body's immune cells reside in the gut-associated lymphoid tissue (GALT), relying on microbial signals to stay balanced.
- Synthesising vitamins: Producing essential micronutrients, including vitamin K and several B vitamins.
- Supporting the gut-brain axis: Communicating with the central nervous system via the vagus nerve and biochemical neurotransmitters like serotonin.
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| HEALTHY MICROBIOME |
| - Diverse microbial species (Lactobacillus, Bifidobacterium)|
| - Strong gut barrier & protective mucosal layer |
| - Production of beneficial Short-Chain Fatty Acids (SCFAs) |
| - Balanced immune response & regular bowel transit |
+-------------------------------------------------------------+
vs
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| DYSBIOSIS |
| - Reduced diversity; opportunistic bacteria dominate |
| - Compromised mucosal barrier |
| - Discomfort, excess gas, bloating, irregular motility |
| - Triggered by stress, poor diet, illness, or antibiotics |
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When the natural equilibrium of this ecosystem is disrupted—a state known as dysbiosis—opportunistic or less helpful bacteria can multiply, while beneficial populations decline. Dysbiosis can arise after a course of antibiotics, during periods of chronic psychological stress, following a gastrointestinal bug, or from a diet low in diverse plant fibres.
Probiotics are defined by the World Health Organization as live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Essentially, they act as temporary reinforcement workers, helping to restore order while your resident microbiome rebuilds its natural balance.
What Probiotics Are Good for Gut Health? The Key Strains
When searching for the right probiotic, looking at the brand name on the front of the box is not enough. You need to look at the specific strain listed in the ingredients.
In microbiology, bacteria are classified by Genus, Species, and Strain:
Understanding Bacterial Names:
- Genus: Lactobacillus (the broad family)
- Species: rhamnosus (the specific member of that family)
- Strain designation: GG or ATCC 53103 (the exact, scientifically studied variant)
Health benefits are strictly strain-specific. Two bacteria from the same species can have completely different effects in the digestive tract. Below are the most extensively researched bacterial groups and strains that support gut health.
1. The Lactobacillus Genus
Lactobacillus species primarily reside in the small intestine and vaginal tract, though they are also found in the colon. They produce lactic acid, which lowers the local pH, creating an acidic environment that discourages unwanted pathogens from multiplying.
Lactobacillus acidophilus
Lactobacillus acidophilus is one of the most widely recognised and researched probiotic species. It naturally inhabits the mouth, stomach, small intestine, and reproductive tract.
- What it does: Helps break down lactose (milk sugar), produces hydrogen peroxide and lactic acid to keep harmful bacteria in check, and supports nutrient absorption.
- When it may help: Helpful as a general daily baseline for digestive comfort, especially if you experience mild gas after dairy meals, or following minor digestive upsets.
Lacticaseibacillus rhamnosus (Specifically Strain GG / LGG)
Formerly classified under Lactobacillus, L. rhamnosus GG is among the most clinically documented probiotic strains in medical literature.
- What it does: It possesses specialised hair-like appendages (pili) that allow it to adhere strongly to the intestinal mucus layer, providing a temporary physical shield against pathogenic microbes.
- When it may help: Clinical studies frequently support its use during or after antibiotic treatment to reduce the risk of antibiotic-associated diarrhoea. It is also widely used by travellers experiencing sudden digestive upset.
Lactiplantibacillus plantarum (e.g., Strain 299v)
L. plantarum is an unusually resilient bacterium naturally found in fermented plant foods such as olives, kimchi, and sauerkraut.
- What it does: Demonstrates exceptional ability to survive harsh stomach acid and bile salts. It metabolises plant fibres efficiently, producing beneficial short-chain fatty acids that nourish the cells lining the large intestine.
- When it may help: Often favoured by individuals who struggle with abdominal cramping, bloating, and excessive gas, as it helps regulate intestinal gas production.
Limosilactobacillus reuteri
Found naturally in breast milk and the human gastrointestinal tract, L. reuteri produces an antimicrobial substance called reuterin, which can inhibit the growth of various harmful bacteria without harming beneficial species.
- When it may help: Supporting overall microbial balance and calming sensitive, reactive digestive systems.
2. The Bifidobacterium Genus
While Lactobacilli are prominent in the small intestine, Bifidobacteria represent one of the most dominant groups of friendly bacteria in the large intestine (colon), particularly in early life and healthy adulthood.
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| WHERE DIFFERENT STRAINS OPERATE |
| |
| Small Intestine: |
| - Dominated by Lactobacillus species |
| - Lowers pH, aids nutrient breakdown |
| |
| Large Intestine (Colon): |
| - Dominated by Bifidobacterium species |
| - Ferments dietary fibre into Short-Chain Fatty Acids |
| - Regulates stool consistency and transit time |
+-------------------------------------------------------------+
Bifidobacterium longum (including B. longum subsp. infantis)
Bifidobacterium longum is a crucial coloniser of the human gut. The infantis subspecies is specifically adapted to digest complex human milk oligosaccharides in babies, but remains valuable in adults.
- What it does: Ferments a broad array of complex carbohydrates, producing acetate and helping to maintain the tight junctions that seal the gut lining.
- When it may help: Often recommended for individuals dealing with general abdominal discomfort, irregular bowel movements, and stress-related digestive tension.
Bifidobacterium animalis subsp. lactis (e.g., Strain BB-12 or HN019)
This is one of the most stable and robust Bifidobacterium strains used in commercial foods and supplements.
- What it does: Enhances gastrointestinal motility (the rate at which food moves through the digestive tract) and supports immune defence mechanisms.
- When it may help: Frequently chosen by people troubled by slow transit time, sluggish bowel habits, and mild constipation.
Bifidobacterium breve
B. breve is an active fermenter of sugars, creating both lactic acid and acetic acid.
- What it does: Works alongside other colon bacteria to maintain a mildly acidic colonic pH, keeping gas-producing and putrefactive bacteria at bay.
- When it may help: Helpful for supporting regular stool consistency and reducing intestinal irritation.
3. Beneficial Yeasts: Saccharomyces boulardii
Not all probiotics are bacteria. Saccharomyces boulardii is a non-pathogenic, tropical yeast first isolated from lychee and mangosteen fruit.
- How it differs from bacteria: Because it is a yeast, it is naturally resistant to antibiotics. This means you can take it alongside a prescribed course of antibacterial medication without the medication killing the probiotic organism.
- What it does: Binds to harmful pathogens and their toxins, encouraging the body to flush them out through the bowel. It also supports the production of Secretory Immunoglobulin A (sIgA)—the primary antibody defending mucosal surfaces.
- When it may help: Widely used during and immediately after antibiotic treatments, for acute bouts of loose stools, and during overseas travel.
Food Sources vs Probiotic Supplements
A common question is whether you should buy a targeted supplement or simply add more fermented foods to your weekly shopping basket. For most people, both approaches have distinct benefits. You can explore more practical ideas in this guide to improving gut health with supplements and everyday habits.
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| FERMENTED FOODS VS SUPPLEMENTS |
+------------------------------------+------------------------------------+
| FERMENTED FOODS | PROBIOTIC SUPPLEMENTS |
+------------------------------------+------------------------------------+
| - Diverse matrix of live microbes | - Defined, measured strains |
| - Provides protein, vitamins, zinc | - Guaranteed CFU counts at expiry |
| - Cost-effective dietary addition | - Targeted for specific needs |
| - Variable bacterial numbers | - No preparation required |
+------------------------------------+------------------------------------+
Probiotic-Rich Fermented Foods
Fermented foods have been prepared across human cultures for thousands of years as a natural preservation method.
- Live Unsweetened Yogurt: Made by fermenting milk with starter cultures (traditionally Lactobacillus bulgaricus and Streptococcus thermophilus). Look for labels that explicitly state "contains live and active cultures".
- Kefir: A fermented milk drink made using kefir grains (a symbiotic matrix of bacteria and yeasts). Kefir generally contains a much broader diversity of live strains than standard yogurt.
- Raw Sauerkraut & Kimchi: Fermented cabbage dishes packed with lactic acid bacteria, fibre, vitamin C, and vitamin K. These must be unpasteurised and refrigerated; shelf-stable canned varieties have been heat-treated, which kills the live bacteria.
- Miso and Tempeh: Fermented soybean products rich in beneficial microbes, protein, and minerals. Add miso paste at the end of cooking, as boiling water can destroy delicate organisms.
- Kombucha: A lightly effervescent fermented tea. While it contains live cultures, opt for low-sugar varieties to avoid feeding unwanted yeasts in the gut.
When Might a Supplement Be Warranted?
While fermented foods provide rich general nourishment, supplements offer precision. If you are recovering from a specific illness, completing a course of antibiotics, or trying to manage targeted symptoms like post-meal bloating, a supplement provides known, quantified strains in therapeutic doses that fermented foods cannot always guarantee.
The Role of Prebiotics and Synbiotics
Taking probiotics without providing them with the right fuel is like planting seeds in barren soil. This is where prebiotics become essential.
Key Terminology:
- Probiotics: Live beneficial microorganisms.
- Prebiotics: Non-digestible plant fibres that selectively feed friendly bacteria.
- Synbiotics: Products or dietary combinations containing both probiotics and prebiotics.
- Postbiotics: The beneficial compounds (like short-chain fatty acids) produced when bacteria ferment prebiotics.
[ Prebiotics (Fibre/Fuel) ]
+
[ Probiotics (Live Bacteria) ]
│
▼
[ Fermentation in the Colon ]
│
▼
[ Postbiotics (SCFAs, Vitamins) ] ---> Strengthens gut wall, balances immune system
Top Prebiotic Foods to Include:
- Inulin and FOS (Fructo-oligosaccharides): Found in chicory root, garlic, onions, leeks, shallots, and slightly green bananas.
- Resistant Starch: Found in oats, cooked and cooled potatoes, cooked and cooled rice, and legumes (lentils, chickpeas).
- Beta-glucans: Found abundantly in whole porridge oats and barley.
A practical caution on "prebiotic sodas" and processed snacks: Many modern ultra-processed snacks and fizzy drinks advertise added inulin or prebiotics on the front label. While these fibres are not harmful in small amounts, consuming them in processed drinks sweetened with sugar or artificial sweeteners is unlikely to deliver genuine gut benefits and may trigger sudden bloating in sensitive individuals.
How to Choose and Take a Probiotic Supplement
If you decide to try a probiotic supplement, navigating the label can feel daunting. Here is a practical checklist to ensure you are purchasing a quality product:
- Check the full strain name: Ensure the label lists the genus, species, and alphanumeric strain designation (e.g., Bifidobacterium lactis HN019, not just "Bifidobacterium").
- Look for Colony Forming Units (CFU): CFU indicates the number of live, viable microorganisms per dose. A general maintenance dose often ranges between 5 billion and 20 billion CFU. Higher numbers (e.g., 50–100 billion) are not automatically better unless clinically indicated for a specific condition.
- Expiry date viability: Look for products that guarantee CFU count at the end of shelf life, not merely at the time of manufacture, as bacteria naturally die off over time.
- Delivery technology: Gastric acid is designed to sterilise food. Look for delayed-release capsules, enteric coatings, or strains clinically proven to survive stomach acid and bile salts.
- Storage requirements: Some delicate strains require refrigeration, while others are freeze-dried and shelf-stable. Check the packaging instructions carefully.
Tips for Starting a Probiotic:
- Start low and slow: If you are new to probiotics or have a sensitive stomach, begin with a half-dose for the first 3 to 5 days to give your digestive tract time to adapt.
- Take with or just before food: Unless the manufacturer's label specifies otherwise, taking your supplement with a light meal containing a little healthy fat can buffer stomach acid and assist survival through the stomach.
- Give it a consistent 4-week trial: Bacterial colonies take time to interact with your native flora. Try a specific strain consistently for 4 weeks while monitoring your symptoms in a daily diary.
When Gut Symptoms Signal Something Else
While an unsettled stomach is common, gut symptoms should never be ignored or simply masked with over-the-counter remedies. Sometimes digestive problems are the primary issue; other times, they are a secondary sign of an underlying medical condition.
Symptoms That Require Urgent GP Review
If you experience any of the following "red flag" symptoms, you should arrange an appointment with your GP promptly:
- Unintentional, unexplained weight loss
- Persistent blood in your stool or dark, tarry stools
- A persistent change in bowel habit lasting more than 4–6 weeks (especially if you are over 50)
- Difficulty swallowing or food feeling stuck
- Unexplained persistent vomiting or fever
- A noticeable lump or swelling in your abdomen
- Waking up during the night to pass loose stools
Safety Note: If you ever experience sudden, severe, incapacitating abdominal pain, chest tightness, or signs of acute collapse, seek urgent medical help via A&E or by dialling 999.
The Systemic Connection: Thyroid, Nutrients, and the Gut
The digestive tract does not operate in isolation. If your gut symptoms persist despite healthy eating and probiotics, it is worth looking at the broader picture. Several systemic conditions mimic or directly cause gut disturbance:
- Thyroid Dysfunction: The thyroid gland sets the metabolic pace for every cell in your body, including gastrointestinal muscles. An underactive thyroid (hypothyroidism) can slow down gut motility, leading to chronic constipation, bloating, and fatigue. Conversely, an overactive thyroid (hyperthyroidism) can cause rapid transit and frequent loose stools.
- Nutrient Deficiencies: If your gut lining is irritated or inflamed, absorption of essential nutrients can drop. Low levels of ferritin (iron stores), vitamin B12, folate, or vitamin D can result in fatigue, brain fog, and reduced mucosal healing.
- Systemic Inflammation: Chronic low-grade inflammation can affect intestinal barrier integrity and alter microbial balance.
For readers exploring whether thyroid function may be contributing to digestive symptoms, our guide to which thyroid tests are used for thyroid function explains the available options.
The Blue Horizon Method: A Structured Approach to Gut Symptoms
Rather than guessing with random supplements, we recommend working through a structured, clinical process to understand what your body needs. You can read more about the wider gut health and microbiome testing options available through Blue Horizon.
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| THE BLUE HORIZON METHOD |
+-------------------------------------------------------------+
| STEP 1: Consult Your GP |
| - Rule out IBD, coeliac disease, infections, red flags |
| |
| STEP 2: Structured Self-Check |
| - Maintain a 14-day symptom, food, and lifestyle diary |
| - Assess fibre diversity, water intake, stress, and sleep |
| |
| STEP 3: Targeted Blood Pathology |
| - Check baseline markers (Thyroid, Ferritin, B12, CRP) |
| - Gather objective data to inform your next GP discussion |
+-------------------------------------------------------------+
Step 1: Consult Your GP First
Always begin with your GP. They can assess your symptoms, perform necessary physical examinations, and arrange standard NHS investigations (such as testing for coeliac disease, inflammatory bowel markers like faecal calprotectin, or routine blood counts) to ensure serious pathology is ruled out.
Step 2: Use a Structured Self-Check
Before spending money on endless supplements, keep a clear 14-day diary. Track:
- What you eat and drink (noting daily plant diversity and water intake)
- When symptoms occur (time of day, relation to meals, stool consistency using the Bristol Stool Chart)
- Lifestyle factors (hours of sleep, exercise, and periods of emotional stress)
Often, patterns emerge—such as symptoms worsening after poor sleep or during stressful work periods—that clarify what is actually driving your discomfort. Blue Horizon’s guide to starting to improve gut health with practical daily habits may help you structure this process.
Step 3: Consider Targeted Blood Testing
If your GP has ruled out acute conditions but you still feel sluggish, bloated, or run down, private blood testing can provide an objective snapshot of your internal health. This is particularly valuable when you want to explore whether systemic imbalances are playing a role.
Evaluating the Broader Picture:
- Thyroid Function: Standard NHS checks often only assess Thyroid Stimulating Hormone (TSH). However, a comprehensive thyroid panel—measuring Free T4, Free T3, and thyroid antibodies (TPOAb and TgAb)—gives a much fuller picture of whether thyroid hormones are affecting bowel transit and energy.
- Nutrient Panels: Checking active vitamin B12, folate, ferritin, and vitamin D (25-OH) ensures your digestive tract has the necessary micronutrients to repair and maintain its mucosal lining.
- Inflammatory Markers: Measuring C-Reactive Protein (CRP) helps identify whether low-grade systemic inflammation is present in the body.
At Blue Horizon, our doctor-led blood tests are arranged in clear tiers—such as our Bronze, Silver, Gold, and Platinum panels—designed to provide comprehensive data without overwhelming you:
- Bronze: Covers core thyroid hormones (TSH, Free T4, Free T3) alongside Blue Horizon Extras: magnesium and cortisol (cofactors that influence stress, bowel muscle relaxation, and energy). You can review the Thyroid Premium Bronze profile for its full inclusions.
- Silver: Includes everything in Bronze plus thyroid antibodies (TPOAb, TgAb) to check for autoimmune thyroid involvement. The Thyroid Premium Silver profile provides the detailed list of markers.
- Gold: Adds key nutritional and inflammatory markers: Ferritin, Folate, Active B12, Vitamin D, and CRP. This tier is ideal for looking at gut-related nutrient absorption alongside metabolic function; see the Thyroid Premium Gold profile for more information.
- Platinum: Our most comprehensive metabolic panel, adding Reverse T3, HbA1c, and a full iron profile (requiring a professional venous blood draw). The Thyroid Premium Platinum profile contains the complete panel details.
Sample collection for Bronze, Silver, and Gold tiers can be performed at home via a fingerprick sample or Tasso device, or via a clinic visit. We recommend taking thyroid-related blood samples around 9am to ensure consistency with natural daily hormone fluctuations. Results provide clear data to share with your GP or specialist, ensuring your health conversations are grounded in evidence.
Practical Daily Habits to Nurture Your Gut
Probiotics work best when supported by daily lifestyle habits that naturally nourish your microbiome. For more background on the connection between digestion, energy, and immunity, explore this overview of how important the gut microbiome is for your health.
1. Aim for 30 Plant Points a Week
Microbial diversity in the gut correlates closely with the diversity of plants in your diet. Rather than eating the same three vegetables every day, aim for a wide variety across the week. Each distinct plant counts as a point:
- Vegetables and fruits
- Whole grains (quinoa, brown rice, barley, oats)
- Legumes and pulses (black beans, lentils, chickpeas)
- Nuts and seeds (walnuts, chia seeds, pumpkin seeds, flaxseeds)
- Herbs and spices (turmeric, rosemary, ginger, garlic)
2. Prioritise Hydration and Regular Movement
Water is essential for the mucosal lining of the intestines and helps dietary fibre pass smoothly through the colon. Aim for 1.5 to 2 litres of water daily. Moderate physical exercise—such as brisk walking, cycling, or yoga—mechanically stimulates intestinal contractions, encouraging healthy, regular transit.
3. Support the Gut-Brain Axis and Stress Response
When your body is in a chronic "fight-or-flight" state, blood flow is diverted away from the digestive tract, digestive enzyme secretion decreases, and gut barrier permeability can increase. Simple practices can help activate the parasympathetic ("rest-and-digest") nervous system:
- Taking five slow, deep diaphragmatic breaths before you begin eating
- Eating meals seated at a table without the distraction of work emails or television
- Chewing each mouthful thoroughly to ease the mechanical workload on your stomach
4. Maintain Consistent Sleep Patterns
Your gut microbiome has its own internal circadian rhythm. Irregular sleep schedules, shift work, and frequent late nights can disrupt microbial balance and alter the expression of genes that control intestinal barrier repair. Aim for 7 to 9 hours of quality, consistent sleep each night.
Summary: Building a Healthier Gut
Supporting your gut is not about chasing the latest wellness trends or buying the most expensive supplement in the pharmacy. It is about understanding how your microbiome works and taking a calm, methodical approach to your health.
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| KEY TAKEAWAYS |
+-------------------------------------------------------------+
| 1. Strain Specificity Matters: Match the exact strain |
| (e.g., L. rhamnosus GG, B. lactis HN019) to your needs. |
| 2. Food First: Incorporate raw fermented foods and high- |
| fibre prebiotics into your weekly routine. |
| 3. Step-by-Step Approach: Always see your GP first for |
| concerning symptoms; track your habits in a diary. |
| 4. See the Whole Picture: Persistent fatigue or motility |
| issues may link back to thyroid, nutrient, or metabolic |
| factors that blood pathology can help illuminate. |
+-------------------------------------------------------------+
If you are experiencing persistent digestive issues, start by visiting your GP to ensure standard investigations are completed. Combine this with a 14-day symptom and food diary to spot lifestyle triggers.
If you remain stuck and want a deeper, structured look at your internal baseline—from thyroid hormone balance to essential nutrient levels like B12, ferritin, and vitamin D—a targeted blood panel can give you the objective data you need to have a more productive, informed conversation with your healthcare provider. You can explore the thyroid blood test collection to compare the available panels and see which option best matches your needs.
FAQ
How long does it take for probiotics to start working?
Probiotics generally begin interacting with your digestive system within a few days, but measurable improvements in symptoms such as bloating, stool consistency, or general comfort typically take between 2 to 4 weeks of daily, consistent use. It is best to trial a specific strain or product for at least a month while tracking your symptoms in a daily diary. If you notice no change after 4 weeks, that specific strain may not be the right match for your gut ecosystem.
Should I take probiotics during or after a course of antibiotics?
Both approaches can be helpful. Taking a probiotic during antibiotic treatment can help reduce the risk of antibiotic-associated diarrhoea. However, because antibiotics kill bacteria, you should space your probiotic supplement at least 2 to 3 hours apart from your antibiotic dose so the medication does not immediately destroy the probiotic strains. Alternatively, taking the beneficial yeast Saccharomyces boulardii is advantageous because, as a yeast, it is naturally unaffected by antibacterial medications. Continuing a multi-strain probiotic for 2 to 4 weeks after finishing your antibiotic course can further support your microbiome's recovery.
Can taking probiotics make gut symptoms like bloating worse?
Yes, for some people, introducing a high-dose probiotic or a product with added prebiotics (such as inulin or FOS) can cause a temporary increase in gas, mild abdominal bloating, or slight changes in bowel habits during the first few days. This usually settles as your digestive tract adapts. To minimise discomfort, start with a lower dose and increase it gradually over a week. If significant cramping, pain, or bloating persists beyond a few days, stop taking the supplement and discuss your symptoms with a healthcare professional.
What is the difference between probiotics, prebiotics, and synbiotics?
Probiotics are live, beneficial microorganisms (such as specific strains of Lactobacillus or Bifidobacterium) that contribute friendly microbes to your digestive tract. Prebiotics are non-digestible plant fibres (such as inulin, resistant starch, and pectin) that act as food to nourish and stimulate the growth of those beneficial bacteria. A synbiotic is simply a supplement or dietary combination that combines both probiotics and prebiotics in a single formulation, ensuring the live microbes have the fuel they need to thrive.
