Overview:

Vivomixx and VSL#3 are both high-strength probiotics, each with 450 billion CFU from eight strains that need cold storage to stay potent. The main difference lies in their history.

Most older studies you’ll see under “VSL#3” tested the original De Simone formulation. That formula now continues as Vivomixx in many regions and Visbiome in the US. The VSL#3 available today carries the same name but is produced differently.

If you want the exact formulation used in those trials, Vivomixx (or Visbiome) is your match. If your priority is a powerful probiotic that’s trusted and accessible in Australia, VSL#3 is often the practical choice. Just make sure to buy from a retailer who ships express, and check in with your health professional before starting.

If VSL#3 or Vivomixx used to be your go-to and now the other pops up everywhere, you are not imagining the mixed messages. Lots of people are asking the same thing. Both sit in the high-potency camp, and both get talked about a lot, which makes the noise even louder. We will keep this friendly, practical and grounded in what matters for your gut.

Your body is processing food all day. With every meal, your gut microbiome shifts a little. That is normal. The probiotic you choose should fit into that rhythm. The right fit can support a healthy gut and help you improve your gut health over time when it sits alongside basics like whole foods, fibre, sleep and stress care.

There is also a bigger picture. A well-balanced gut talks to your immune system and your brain. That is why people often link the gut with mental health and overall health. None of this is about quick fixes. It is about picking a product that matches your goals and using it consistently.

So let’s untangle the history, explain what changed and what stayed familiar, and help you choose the option that suits your routine and your gut.

Why all the confusion?

It helps to think of it like a chef and a restaurant. For years, a well-known recipe was served under the name VSL#3. When the partnership ended, the chef took the original recipe and continued it elsewhere under new names — Vivomixx in Europe and Visbiome in the US. The restaurant kept the old name, VSL#3, but began serving a different recipe.

That’s why articles, reviews, and even research papers can feel contradictory. People are often talking about the same name but not the same formulation. When you search Vivomixx vs VSL3, what you’re really looking for is clarity on which product today supports your gut microbiome, immune system, and overall health in a way that fits your goals.

Vivomixx at a glance

What’s inside?

Vivomixx contains eight strains, including Streptococcus thermophilus, several Bifidobacterium species, and several Lactobacillus species. Each 4.4 g sachet provides 450 billion CFU. The labels list the exact strain identifiers, which helps with transparency.

These strains are intended for broad gut microbiome support, which can influence digestion, immune system balance, and day-to-day comfort.

How should it be handled?

Vivomixx must be kept refrigerated at 2–8 °C. Unopened sachets can handle a short period at room temperature, which helps during travel or delivery, but it’s best to keep them cold to protect potency.

Storing cold helps protect viability, which matters if your goal is to improve your gut health and maintain a healthy gut.

Who is it for?

Vivomixx is often chosen by people who want to stay close to the body of research originally labelled as VSL#3 in clinical trials. It can appeal to gut health enthusiasts who like knowing the exact strain names, as well as those working with practitioners on targeted gut support.

This can be a fit if you are focused on overall health outcomes and you want a product that supports the gut microbiome while your body is processing food all day long.

VSL#3 at a glance

So, what are you buying?

In Australia, VSL#3 is available as an 8-strain, 450-billion CFU probiotic sachet. Like Vivomixx, it needs to be stored refrigerated when you receive it.. While today’s formulation is not identical to the original De Simone recipe, many people still turn to VSL#3 because it is well-recognised, locally available, and backed by years of practical use.

It’s less about comparing old research line by line, and more about asking: does this product fit into my routine, my diet, and my wider approach to gut health? For many, the answer to VSL#3 is yes.

Who does it suit?

VSL#3 makes sense if you want a high-potency probiotic you can buy in Australia without jumping through hoops. It works well for people who want a product they can trust to support a healthy gut, help balance the gut microbiome, and contribute to overall health in a consistent, practical way.

What the research really says

A simple way to read the science is this: match the product in your hand to the product in the paper.

Pouchitis: Randomised trials using the original formulation found it helped maintain remission in chronic pouchitis after antibiotics. In one study, most patients who took the probiotic stayed in remission at one year, compared with very few on placebo. Clinical guidelines note this evidence when discussing treatment options.
Ulcerative colitis: Several trials and reviews explored high-potency probiotics as an add-on to standard care in mild to moderate UC. Results vary, but overall they suggest a role for multi-strain probiotics in helping some people reach remission when guided by a clinician.
IBS: Results here are mixed. Some studies showed symptom improvements, while others didn’t. That’s common in IBS research — outcomes depend on the strain, dose, and duration. It’s a reminder that probiotics are not one-size-fits-all.

Bottom line from the science: High-strength blends can be useful, especially for specific conditions like pouchitis. But results depend on the formulation and the person. If your goal is to improve your gut health day to day, focus on products you can access consistently, that fit your lifestyle, and that have a reputation for quality. For Australians, VSL#3 often ticks those boxes.

How to choose with confidence

Start with your goal

Are you looking to support remission after antibiotics, ease ongoing digestive issues, or simply strengthen your gut microbiome as part of better energy, mental health, and overall health? Write that goal down — it will guide your decision.

Check the strains

Labels that list specific strains (not just species) give you clarity. It shows you exactly what you’re putting into your body, and helps you align with research where it exists.

Look beyond the numbers

450 billion CFU sounds impressive, and it is. But more is not always better. What matters is how the strains work together and whether the product fits your needs. Think of CFU as one piece of the puzzle, alongside fibre, diet, sleep, and the way your body is processing food every day.

Keep it cold

Both Vivomixx and VSL#3 need refrigeration when you receive it. Always buy from a retailer that stores and ships express.

Work with a professional

If you’re managing IBD, IBS, or other ongoing issues, involve your gastroenterologist or practitioner. Probiotics are part of the bigger picture — one that includes diet, prebiotics, lifestyle, and sometimes testing.

Bringing it all together

When you read about Vivomixx vs VSL3, you’ll see the shared history but also the differences. Vivomixx carries on the original formulation under a new name. VSL3 continues under its own path. Both have their place, but if you’re in Australia and want a product that is accessible, trusted, and easy to integrate into your routine, VSL3 often feels like the practical choice.

At the end of the day, it’s not about which product “wins,” but which one fits your healthy gut goals and helps you feel your best.

Buying in Australia and getting the right support

If you decide to try VSL#3, choose a specialist retailer who understands gut health and takes care with express delivery. Nourishme Organics is an Australian store focused on evidence-informed gut health, fermented foods, and practitioner-grade supplements. You’ll get refrigerated shipping for heat-sensitive products, plus support on how to pair probiotics with diet and lifestyle so you can really improve your gut health.

Frequently asked questions

Are Vivomixx and VSL#3 the same product?

Not anymore. They share the same roots, but they’ve taken different paths. For years, clinical trials used a blend known as the “De Simone formulation,” which was sold under the VSL#3 name. After 2016, that original formula was continued under the names Vivomixx (in many regions) and Visbiome (in the US). The VSL#3 you see on shelves today is made differently, even though it carries the same name and strength. This is why the conversation around Vivomixx vs VSL3 can feel confusing — they’re connected historically, but they aren’t identical products anymore.

Why do some articles still say VSL#3 when they mean the original formulation?

It comes down to timing. When the early studies were published, the product was sold under the VSL#3 name. Years later, the original formula continued under Vivomixx and Visbiome. But research papers, blogs, and even healthcare professionals sometimes keep using the old name, even though the recipe changed hands. It takes time for the language to catch up — so if you’re reading older studies, remember that “VSL#3” might actually mean what we now call Vivomixx or Visbiome.

Which has stronger evidence for pouchitis?

The clearest evidence is for the original De Simone formulation. In several trials, patients with pouchitis who took the probiotic stayed in remission much longer compared with those on a placebo. That’s significant. If you’re aiming to follow the evidence literally, Vivomixx (or Visbiome in the US) reflects that research history. That said, VSL#3 is still chosen by many people in Australia because it’s accessible, practitioner-trusted, and easier to integrate into daily life. If pouchitis or IBD is a concern for you, it’s best to review these options with your gastroenterologist.

Does VSL#3 still have 450 billion CFU and 8 strains?

Yes, it does. The current Australian VSL#3 contains 450 billion CFU and lists eight strains on the label. While it’s not the same formulation used in older studies, it remains one of the most potent probiotics you can buy locally. The strength and multi-strain approach are why many gut health enthusiasts reach for it when they want more than just an everyday probiotic.

What exactly is in Vivomixx?

Vivomixx is very transparent about its strain list. Each sachet contains 450 billion CFU from eight named strains: Streptococcus thermophilus, Bifidobacterium longum, B. breve, B. infantis, Lactobacillus acidophilus, L. plantarum, L. paracasei, and L. delbrueckii subsp. bulgaricus. Each has been carefully chosen to work together in supporting the gut microbiome, immune system balance, and digestive function.

Do both need to be kept in the fridge?

Yes — refrigeration is essential. Both Vivomixx and VSL#3 should be stored at 2–8 °C to keep the bacteria alive and effective. Both allow for a short room-temperature window while unopened, which helps for travel or shipping, but ideally, both products should go straight back in the fridge when you get them home. Think of cold storage as part of the investment in keeping your probiotics potent.

How long should I try a probiotic before judging results?

Give it time. A realistic window is 4 to 8 weeks, unless your practitioner advises otherwise. During that period, keep track of simple things like bloating, stool consistency, energy levels, and overall comfort. The gut microbiome doesn’t transform overnight, so consistency is key. If you notice changes earlier, that’s a bonus, but patience usually pays off.

Can I take these with antibiotics?

Many people do, often leaving a gap of a few hours between the antibiotic and probiotic dose. The idea is to give the probiotic a better chance to reach your gut. That said, timing can vary depending on the antibiotic, so it’s always best to check with your doctor or pharmacist. They’ll help you get the most from both.

Are these suitable if I have a diagnosed condition like IBD?

They can be, but this is where professional guidance is important. There is published evidence for the De Simone formulation in certain IBD contexts, particularly pouchitis and ulcerative colitis. However, every case of IBD is unique, and what works for one person may not work for another. If you’re living with a chronic condition, decisions about probiotics should always be made with your gastroenterologist.

What if I am sensitive to probiotics?

It happens. Some people feel gassy, bloated, or unsettled when they first start a high-strength probiotic. The best approach is “low and slow.” Try half a sachet, see how you go, and build up gradually. If symptoms continue or feel uncomfortable, pause and talk with your practitioner. Your gut microbiome is unique, so it’s worth finding the pace that works for you.

Where should I buy in Australia?

Always buy from a retailer that understands gut health and handles probiotics with care. Heat can kill potency, so cold-chain storage is non-negotiable. Nourishme Organics is one of the few Australian retailers that specialises in this. Not only do they ship VSL#3 refrigerated, but they also provide education and guidance on how to use probiotics alongside diet, prebiotics, and lifestyle changes. That way, you’re not just buying a product — you’re building a plan to truly improve your gut health.