A Supplement Isn’t a Medicine. So Stop Marketing It Like One.

1. Why Claims Matter

Walk into a pet shop, visit an online supplement store or scroll through social media and you'll find an enormous number of products promising to support your dog's joints.

Some simply explain what their products contain.

Others go much further.

You may see statements suggesting that a supplement can increase mobility, ease joint discomfort, relieve stiffness, improve joint function or produce noticeable results within a particular timeframe.

To a dog owner, these statements may sound like ordinary marketing.

But there is an important distinction that is easy to overlook:

Describing what a supplement contains is not the same as claiming what that supplement will do to an animal's health.

And that distinction matters.

Supplements Have a Place. So Do Boundaries.

There is nothing inherently wrong with using nutritional supplements as part of a dog's overall health and wellbeing.

Ingredients can provide nutrients, compounds and other nutritional components that have recognised biological roles within the body. A thoughtfully formulated supplement may therefore have a legitimate nutritional purpose.

The problem begins when marketing moves beyond explaining that nutritional role and starts presenting the product as something that will treat, relieve, restore, correct or change a health problem or physiological function.

At that point, the language being used is no longer simply describing nutrition.

It is making a claim about an outcome.

The VMD Has Been Clear About This

In January 2026, the Veterinary Medicines Directorate (VMD) published updated guidance on the advertising of non-medicinal veterinary products.

The guidance is particularly relevant to products such as animal feeds and supplements that are marketed for use in animals but are not authorised veterinary medicines.

Importantly, the VMD states that the underlying legislation has not changed. The updated guidance is intended to clarify how the existing requirements apply and to help businesses understand what is and is not acceptable when advertising these products.

That matters because the rules aren't limited to what appears on a product label.

The VMD's guidance applies to advertising across a range of channels, including websites, product pages, social media, downloadable material, scientific references and testimonials.

In other words, a claim does not become acceptable simply because it appears in a Facebook post rather than on the side of a tub.

Why This Is Important for Dog Owners

When a company tells you that its supplement will increase your dog's mobility or ease joint discomfort, it is making more than a statement about ingredients.

It is telling you what you can expect the product to do.

That distinction is particularly important when the subject is a condition such as osteoarthritis, joint pain or reduced mobility.

These are health issues that can require proper veterinary assessment, diagnosis and management.

A nutritional supplement should not be marketed in a way that creates the impression that it is an alternative to that process.

This is why responsible marketing matters.

It's Not About Being Afraid of Science

There is sometimes a misconception that regulatory compliance means supplement companies cannot talk about science.

That isn't the point.

In fact, we believe the opposite.

Consumers should be given more information about ingredients, formulation, research and evidence, not less.

But there is a fundamental difference between saying:

“This ingredient has a recognised nutritional role in normal joint health.”

and saying:

“This product will increase your dog's mobility and ease its joint discomfort.”

The first is describing a nutritional role.

The second is making a specific claim about an animal's health and physical function.

Understanding that difference is at the heart of this article.

2. What Does the VMD Actually Say?

So far, we've talked about the principle.

Now let's look at what the regulator actually says.

The Veterinary Medicines Directorate (VMD) published its updated guidance on advertising non-medicinal veterinary products in January 2026. The guidance makes an important point:

Non-medicinal veterinary products may only be presented for maintaining health in healthy animals.

They cannot be advertised as having medicinal properties or effects, or as treating or preventing disease, or as restoring, correcting or modifying physiological functions.

That distinction is not a matter of opinion. It reflects the regulatory framework governing veterinary medicines in the UK.

And it becomes particularly important when we look at some of the claims currently being made in the canine supplement market.

We Are Seeing These Claims Being Made

Let's be completely honest.

There are companies selling canine joint supplements that make statements along the lines of:

• “Higher levels will increase mobility.”
• “Ease joint discomfort.”
• “Increase your dog's mobility in four weeks.”
• “High levels of active ingredients make a real difference to mobility.”

These aren't simply statements about what a product contains.

They are claims about what the product will do to the animal.

And that is precisely where the VMD's guidance becomes relevant.

Let's Take One Claim Apart

Consider a statement that says:

At first glance, it might sound like a perfectly ordinary supplement claim.

But look at what the statement is actually saying.

It isn't simply saying that the product contains a particular quantity of an ingredient.

It isn't explaining the nutritional role of that ingredient.

It isn't saying that the ingredient forms part of a nutritional approach to maintaining normal health.

It is making a direct promise about an animal's physical function and symptoms.

Higher levels → increased mobility → reduced discomfort.

That is an entirely different type of statement.

“Increase Mobility” Is Not Just Another Way of Saying “Support Joints”

This distinction is particularly important.

The VMD's guidance explains that modifying physiological function includes claims about making an animal's systems, anatomy or health “better than normal”. The guidance specifically identifies enhancement-style language such as “boosting”, “better”, “promotes” and “stronger” as potentially relevant to this assessment.

The VMD also makes clear that the list of problematic terminology is not exhaustive.

So when a company tells consumers that its supplement will increase a dog's mobility, it is not simply describing the product's nutritional composition.

It is claiming that using the product will produce a change in how the animal functions.

That is exactly the sort of distinction businesses need to understand when advertising a product that is intended to remain non-medicinal.

And Then There Is “Joint Discomfort”

The phrase “ease joint discomfort” takes the claim another step further.

Discomfort is not an ingredient.

It isn't a nutritional component.

It is a description of how an animal is experiencing a problem.

So telling a dog owner that a supplement will ease joint discomfort isn't simply telling them what nutritional support the product provides.

It is presenting the product as capable of changing a symptom.

That is precisely why the distinction between a nutritional supplement and a veterinary medicine matters.

A veterinary medicine is specifically regulated for its medicinal properties and effects. A product marketed as a non-medicinal supplement cannot simply adopt medicinal-style claims because those claims are attractive to consumers.

“But It's Only Marketing” Isn't an Answer

One possible response is that consumers understand these statements as marketing language.

But the VMD's guidance does not treat advertising as somehow separate from the regulatory status of the product.

The VMD explains that a product can become medicinal by presentation when its marketing gives the average well-informed person the impression that it treats or prevents disease.

That presentation can include product labels, websites, social media advertisements, leaflets and other literature.

So a company cannot necessarily avoid the issue by putting a carefully worded label on its packaging while making much stronger promises on social media.

The advertising as a whole matters.

And This Is Not About One Company

We are deliberately not naming individual businesses here.

That's not the point of this article.

The point is that these types of claims are being used across the supplement industry, and dog owners deserve to understand what they are actually being told.

If a company tells you that a higher dose will increase your dog's mobility, that is a claim about an outcome.

If it tells you that its product will ease joint discomfort, that is a claim about a symptom.

If it promises a measurable improvement within a specific number of weeks, that is a claim about a predictable physiological outcome and timeframe.

These are very different from simply explaining the nutritional role of an ingredient.

Sources: Veterinary Medicines Directorate, Advertising non-medicinal veterinary products; Veterinary Medicines Directorate, Placing non-medicinal veterinary products on the market – use of specific words and phrases.

3. Supporting Health Is Not the Same as Claiming an Outcome

This is where things become particularly important.

Because the difference between an acceptable nutritional claim and a medicinal claim isn't always obvious at first glance.

A company can quite legitimately explain what an ingredient is, why it has been included in a formulation and what nutritional role that ingredient has within the body.

What it cannot simply do is take that information and turn it into a promise about what the product will do to an animal.

That is the line we need to understand.

There Is a Big Difference Between “Supports” and “Changes”

Consider these two statements:

This is describing the purpose of nutritional support.

Now compare it with:

This is no longer simply describing nutritional support.

It is telling the customer that the product will produce a particular change in the animal.

That distinction is fundamental.

Think About What the Customer Is Actually Being Promised

One of the easiest ways to understand the difference is to ignore the ingredient list for a moment and look at the promise being made to the customer.

Ask:

• Is the company explaining what the ingredient is?
• Is it explaining the nutritional role of the ingredient?
• Is it describing the product as part of maintaining normal health?

Or is it saying:

• your dog's mobility will improve;
• your dog's discomfort will reduce;
• your dog's stiffness will disappear;
• your dog's joint function will improve; or
• you will see a measurable result within a particular timeframe?

The second group contains outcome-based claims.

They tell the consumer what they should expect the product to do.

Let's Look at Some Common Examples

The following examples illustrate why wording matters.

This is why simply looking at whether a product contains good ingredients isn't enough.

The ingredients might be perfectly legitimate. The problem can be the claim being attached to them.

“But We Said ‘Supports’”

This is another area where consumers can easily be misled.

It is tempting to think that adding a word such as “supports”, “may” or “can” automatically makes a statement acceptable.

It doesn't.

The VMD's guidance makes clear that individual words need to be considered in their context. Its guidance on specific words and phrases also makes clear that the list of potentially medicinal wording is not exhaustive. [oai_citation:1‡GOV.UK](https://www.gov.uk/guidance/placing-non-medicinal-veterinary-products-on-the-market-use-of-specific-words-and-phrases?utm_source=chatgpt.com)

So this:

doesn't magically become a nutritional statement simply because the word “supports” has been placed at the beginning.

The overall message is still telling the consumer to expect increased mobility and relief from discomfort.

This is why responsible compliance cannot be reduced to finding a few “safe” words and putting them in front of an otherwise medicinal claim.

What About “High Strength”?

This is particularly relevant to joint supplements.

There is nothing inherently wrong with telling a customer how much of an ingredient a product contains.

Transparency about formulation is important.

For example, stating the quantity of glucosamine, collagen, MSM or another ingredient per recommended daily serving allows consumers to compare products more intelligently.

The problem arises when that quantity is then used to make a medicinal promise.

Consider the difference:

versus:

The first is a statement about what the product contains.

The second is a statement about what the product will do.

Those are fundamentally different claims.

Why This Matters Even More With Joint Supplements

Joint supplements are often marketed towards dogs that are already showing signs of reduced mobility, stiffness or discomfort.

That creates an additional responsibility for the businesses selling them.

A dog owner who sees a statement promising to ease discomfort may reasonably interpret that as meaning the product is capable of addressing the problem causing that discomfort.

A statement promising to increase mobility may similarly be interpreted as an assurance that a dog's physical function will improve.

Those aren't insignificant promises.

They can influence whether an owner seeks veterinary advice, what product they purchase and what they expect that product to achieve.

That is precisely why the distinction between nutritional support and medicinal claims matters.

The VMD's Approach Is About More Than Individual Words

The VMD explains that a product can be medicinal by presentation where the product information or marketing gives an averagely well-informed person the impression that the product treats or prevents disease.

This can include labels, leaflets, websites, social media advertisements and other literature relating to the product. That is an important principle.

It means compliance cannot simply be about finding one word that appears on a list of acceptable terminology.

Context matters. The overall impression matters. The promise being made matters.

4. The Words Matter: What Can You Actually Say?

By now, the distinction should be becoming clearer.

But there is another important part of the VMD guidance that every supplement company and every consumer should understand.

Some words and phrases have a recognised medicinal meaning when used in connection with veterinary products.

In January 2026, the VMD published specific guidance on words and phrases that may cause a non-medicinal veterinary product to become medicinal by presentation.

The VMD is very clear that this is a guide rather than an exhaustive list. A word not appearing on the list does not automatically make a claim acceptable, and the context in which a word is used matters.

Nevertheless, the list makes for some very interesting reading.

A Few Words That Should Make You Stop and Think

Important: The VMD states that its list is not exhaustive. Whether wording is medicinal can depend on how it is used and the overall presentation of the product.

“Increase Mobility” Is Particularly Interesting

There is an important phrase that does not appear as a standalone entry in the VMD's specific-word table:

That does not mean the phrase is automatically permitted.

The VMD specifically explains that “modifying” physiological function includes claims that change how an animal functions. It gives examples such as “boosting”, “better”, “promotes” and “stronger”, and states that the list of examples is not exhaustive.

The guidance also gives a particularly relevant example: a product presented as restoring joint function in dogs that can barely walk would be medicinal.

So we need to look at what a statement such as “increase mobility” is actually promising.

It isn't simply saying that the product contains a particular nutrient.

It isn't simply explaining the role of an ingredient.

It is telling the customer that using the product will result in a change in the dog's physical function.

That is exactly why businesses should not assume that a phrase is acceptable simply because it doesn't appear word for word in the VMD's list.

And “Ease Joint Discomfort”?

This is even more straightforward.

The VMD specifically identifies “relieve / relief” as wording that may be medicinal when a product is presented as offering relief from a disease or its symptoms.

“Discomfort” is describing a symptom or adverse health experience.

So telling a customer that a supplement will ease that discomfort is not simply a description of nutritional support.

It is a claim about the effect the product will have on a symptom.

What About “Support”?

This is where things become more nuanced.

“Support” is not a magic compliance word.

But it can be perfectly legitimate when it is genuinely being used to describe health maintenance.

The VMD itself explains that the word “support” is often used as an alternative to “maintain” and can follow the same rules.

For example:

This is fundamentally different from:

The second statement is still communicating the same outcome: better physical function and reduced symptoms.

Changing the first word to “supports” doesn't change the meaning of the promise.

The Word “Improve” Deserves Particular Attention

This is one of the clearest examples in the VMD's guidance.

The VMD specifically states:

So when you see a supplement advertised with language such as:

• “Improve mobility”
• “Improve joint function”
• “Improve movement”
• “Improve your dog's quality of life”

that should immediately prompt a closer look at the context and the overall claim.

It is not enough to say, “But we're only talking about a supplement.”

The VMD's guidance applies precisely because a product's presentation can determine whether it is considered medicinal.

Why This Matters for the Industry

We don't believe responsible supplement companies should need to make medicinal promises to demonstrate that their products are worthwhile.

We should be able to talk openly about ingredients.

We should be able to explain formulation.

We should be able to discuss published research where appropriate.

And we should be able to tell consumers exactly what they are buying.

But there should also be a line.

A non-medicinal supplement should not be marketed as though it were a medicine simply because medicinal style claims are more persuasive.

Source: Veterinary Medicines Directorate, Placing non-medicinal veterinary products on the market – use of specific words and phrases, published 14 January 2026. [oai_citation:1‡gov.uk](https://www.gov.uk/guidance/placing-non-medicinal-veterinary-products-on-the-market-use-of-specific-words-and-phrases?utm_source=chatgpt.com)

5. What Should Responsible Supplement Marketing Look Like?

After everything we've covered, it would be easy to focus on what companies shouldn't say.

But there is another, more positive question:

What should responsible marketing of a canine supplement actually look like?

We don't believe the answer is to stop talking about ingredients, science or formulation.

Quite the opposite.

Consumers deserve more information, not less.

Tell People What They're Actually Buying

A good supplement company should be able to explain:

• what ingredients are in the product;
• how much of each ingredient is provided;
• why those ingredients have been selected;
• the nutritional role those ingredients have;
• how the product is intended to be used; and
• what evidence exists to support the formulation.

None of that requires a medicinal promise.

In fact, we believe this is a much more honest way to market a supplement.

Rather than telling a customer, “Give your dog this and their mobility will improve,” explain what the product contains and why those ingredients have been included.

Let consumers make informed decisions based on the information provided.

Be Transparent About Amounts

We also believe consumers should be able to see the actual quantities of ingredients provided by a recommended daily serving.

There is nothing inherently wrong with discussing formulation strength or ingredient levels.

The important distinction is what you do with that information.

It is perfectly reasonable to tell someone:

It is a very different statement to say:

The first gives the customer information.

The second gives the customer a promise.

That distinction is at the heart of responsible supplement marketing.

Use Science to Educate — Not to Make a Medicine Out of a Supplement

We are strong believers in evidence based formulation.

Scientific research can help us understand ingredients, biological pathways, nutritional requirements and how different compounds interact within the body.

But scientific information needs to be presented responsibly.

The VMD specifically warns that research and studies can themselves become advertising material when they are presented in connection with a product. It also states that research must not be used to associate a non-medicinal product with a medicinal purpose or effect. 

That means a scientific paper shouldn't simply become a shortcut to a claim.

“A study investigated X” is not automatically the same as “our product does X.”

Those are very different statements.

Don't Hide Behind “May Help”

There is another practice we believe consumers should be aware of.

Sometimes a strong medicinal claim is softened by adding words such as:

• “may”;
• “could”;
• “can”;
• “might”; or
• “supports”.

But wording alone does not change the underlying meaning.

The VMD specifically states that saying a product “may help” does not protect a business from making an unauthorised medicinal claim. If the underlying claim is medicinal, adding uncertainty does not make it acceptable.

That is an important lesson.

Compliance isn't about finding clever ways around the rules. It's about making a fundamentally appropriate claim in the first place.

What We Believe Good Marketing Looks Like

At Kater4K9, we believe a supplement should be able to stand on the quality of its formulation and the transparency of the information provided.

That means being prepared to tell customers:

• what is in the product;
• how much is provided;
• why it has been included;
• what the available evidence tells us;
• where evidence is strong;
• where evidence is limited or mixed; and
• where we simply don't know.

We don't believe consumers should have to be given a dramatic promise in order to believe that a product is worthwhile.

And we don't believe a bigger claim makes a better supplement.

And This Is Why We Think the VMD Guidance Matters

The VMD's updated guidance isn't there to stop businesses talking about supplements.

It is there to establish the boundary between a non-medicinal product and something being presented as having medicinal properties or effects.

The VMD says non-medicinal veterinary products may be presented for maintaining health in healthy animals. It also makes clear that products must not be presented as treating or preventing disease, or restoring, correcting or modifying physiological functions.Those boundaries exist for a reason.

Consumers need to know what they are buying.

And when a product is being marketed towards owners of animals experiencing genuine health problems, the language used to sell that product matters.

That is why we believe claims such as “increase mobility” and “ease joint discomfort” should not simply be dismissed as harmless marketing language.

They are claims about an animal's health and physical function.

And businesses selling non-medicinal supplements have a responsibility to understand where that language crosses the regulatory line.

6. Key Takeaways

The VMD's January 2026 guidance gives businesses and consumers a much clearer framework for understanding the difference between nutritional support and medicinal claims.

Final Thoughts

The canine supplement market is crowded, competitive and full of increasingly confident claims.

But confidence isn't evidence.

A bigger number isn't automatically a better formulation.

A longer ingredient list isn't automatically a better product.

And a more dramatic promise isn't automatically a more credible one.

The VMD's guidance provides an important reminder that there is a line between nutritional support and medicinal claims.

We believe that line should be respected.

Not because supplement companies should be prevented from talking about their products.

But because dog owners deserve to know whether they are being given information about a nutritional product or being promised a medical outcome.

At Kater4K9, we'd rather give you the information and let you make an informed decision.

7. VMD Guidance & References

This article is based primarily on the Veterinary Medicines Directorate's current guidance, published on 14 January 2026.

Primary Regulatory Sources

1. Veterinary Medicines Directorate – Advertising non-medicinal veterinary products
   The VMD's comprehensive guidance covering medicinal by presentation, health-maintenance claims, advertising, testimonials, research, social media and prohibited medicinal claims.
2. Veterinary Medicines Directorate – Use of specific words and phrases
   The VMD's guidance on terminology that may cause a non-medicinal product to become medicinal by presentation. The VMD states that this list is not exhaustive and must be considered in context.
3. Veterinary Medicines Directorate – Updated guidance published January 2026
   The VMD's announcement explaining why the guidance was updated and confirming that the underlying law has not changed.