The Numbers Are In: What Our Largest Trial Yet Revealed About Calmer Dogs

Most supplement studies in this category run on a handful of dogs, often eight to twenty, and are rarely repeated or published anywhere anyone can check them. So when we set out to properly test CaniNectar, we didn't want a small, one off snapshot. We wanted something big enough, and repeated enough, that the results could actually be trusted.

Over two independent phases, run months apart, 63 UK veterinary professionals, trainers and behaviourists tracked 129 dogs across more than 110 distinct breeds and crosses while they were on CaniNectar. What came back is the clearest, most consistent signal we've seen from any of our research to date, and it's about the thing owners ask us about more than almost anything else: anxiety.

The headline: dogs got calmer, and it wasn't a fluke

Among the dogs that started the trial with elevated anxiety, professionals recorded a meaningful and fairly rapid drop within the first few weeks of supplementation. Here's what the data showed:

• 38 of 42 anxious dogs improved, with only one dog rated as worse
• Mean anxiety score fell from 4.29 to 3.23 out of 5, a reduction of about a full point, or roughly 24.7%
• The statistics behind this are about as solid as they come in a study of this kind: p < 0.0001, with an effect size at the theoretical maximum (r = 1.00)
• Handler confidence in the product climbed steadily too, from 31% in week one to 73% by week four

The part that matters most, though, is that this result wasn't a one off. The trial was deliberately run in two completely separate phases, each with different dogs and different professionals, so that we could see whether the pattern would hold up under fresh conditions rather than being a quirk of one particular group. Phase one produced a 1.04 point reduction in anxiety, and phase two, run independently later, produced a 1.10 point reduction. Combined, the calculated probability that this calming effect is simply down to chance works out to roughly 1 in 1.6 million, which is in the same ballpark as the odds of being struck by lightning in any given year.

It also didn't seem to matter much what the dogs were eating. Dogs on raw diets, kibble and mixed feeding all became calmer by essentially the same amount. That consistency across diets is exactly what you would expect if something is genuinely working on the gut brain axis, rather than the effect being tied to any one particular food or feeding style.

It wasn't just about behaviour

The same professional trial, alongside an independent 2025 study run with Blue Cross involving 25 rescue dogs, turned up consistent improvements in several other areas too:

• 80% of dogs reached ideal stool consistency by week four in the Blue Cross trial, up from 41.7% at the start
• A 33% reduction in noise reactivity was recorded in the same study
• 29.2% of dogs showed a clinically significant improvement in skin condition
• Handler focus scores rose too, with the proportion of dogs rated as having excellent focus increasing from 4.2% to 20.8%
• Across all four studies combined, covering 259 dogs in total, there were zero serious adverse events recorded at any timepoint, from four weeks right through to the two year follow up

Professionals who watched these changes happen said as much in their own words. One behaviourist noted that a dog's "general calmness, anxiety and reactivity improved significantly," while a veterinary nurse reported that her patient's owner had "started allowing him out of the crate when I am not home" once his anxiety began to ease. Another trainer described a dog as "much calmer overall, more confident with dogs and less reactive to sounds."

Why this happens: it starts in the gut, not the head

The mechanism behind all of this traces back to a single upstream process, rather than several unconnected effects. CaniNectar's enzyme rich malt extract helps break food down more completely in the small intestine, which means less undigested material reaches the colon to feed the wrong kinds of bacteria there. That shift, in turn, changes fermentation patterns towards beneficial short chain fatty acids. In peer reviewed testing published separately from the professional trial, butyric acid rose by 73.5%, propionic acid by 64.8%, and acetic acid by 44.8%.

These compounds matter enormously for behaviour because somewhere between 90 and 95% of the body's serotonin is actually produced in the gut, not the brain, and the vagus nerve carries that chemical signalling directly from one to the other. A calmer, healthier gut appears to translate fairly directly into a calmer dog, and B vitamins delivered by the same product (particularly B6, a cofactor for both serotonin and GABA production) may help explain why behavioural change is often reported within just three to six days of starting supplementation, well before any longer term microbiome shift would typically take hold.

Supporting evidence: what an earlier, smaller study hinted at

Before this larger professional trial took place, an exploratory analysis carried out by data analyst Lee Mager, looking at a group of UK Border Force working dogs, had already pointed in a similar direction. Mager's study was much smaller and more cautious in its conclusions, but it turned up a genuinely interesting pattern: older dogs, those aged five years and above, seemed to benefit the most, showing notably better dropping and appetite ratings than the younger dogs in the same sample, by a factor of around 2.3 and 4.2 times respectively.

One dog in that dataset, Willow, stood out in particular, with the single largest improvement across nearly every handler rating category alongside a clear increase in the relative abundance of "good" gut bacteria such as Faecalibacterium, and a corresponding drop in less favourable genera. Mager was careful throughout the report to stress that nothing in such a small, exploratory sample should be generalised too broadly, and that reductive labels like "good" and "bad" bacteria inevitably oversimplify an extraordinarily complex microbiome. Even so, it's reassuring to see some of the same underlying themes, older dogs responding particularly well, and gut bacteria shifting in a favourable direction, show up again independently at a much larger scale in the professional trial described above.

Where this leaves us

We're not calling CaniNectar a calming supplement, and it isn't a substitute for proper veterinary care. This was an observational trial: the professionals involved knew which dogs were on the product, and there was no placebo group, so the design can't fully rule out other influences on the results. What gives these findings their weight is that the effect repeated independently, twice, in different dogs assessed by different observers, and that it lines up closely with what published gut brain axis research would predict in the first place.

The strongest possible claims will come once a fully randomised, blinded study confirms what four separate pieces of research have now consistently pointed towards. Until then, this remains the most solid evidence we've gathered that a healthier gut really can mean a calmer, more comfortable dog, and it's evidence we're proud to be able to share openly.

Sources: UK Professional Trial Phases 1 and 2 (2025 to 2026, 129 dogs, 63 professionals); Blue Cross independent clinical trial (2025, 25 dogs); Waring, Dagi and Hunter, Journal of Modern Agriculture and Biotechnology (2024); UKBF working dogs study and two year follow up (Mager, 2023).