Summary of Council decision:

Seven issues were investigated, all of which were Upheld

Ad description

A magazine ad for a horse supplement that made efficacy claims for the role of chelated calcium as a horse calmer and additional claims about the negative effect of magnesium on horse behaviour. The ad referred to the advertiser's trials and experience of the product.


The complainant challenged whether the following claims were misleading and could be substantiated:

1. "Our experience since 2009 suggests chelated calcium works incredibly well as a calmer ... allowing horses to be good risk assessors so they are less distracted, better focused and more confident";

2. "According to Equifeast's blood trials, if you feed a lot of magnesium, the blood magnesium levels rise, feed too little and they drop";

3. "This approach to 'calming' can have a negative effect on behaviour. This is because excess magnesium blocks the calcium receptors in nerve cells, impairing normal function. This can lead to horses which are sedated in a relaxed environment but explosive under stress";

4. "Equifeast's trials suggest that the provision of chelated calcium ... also helps the horse to control its blood magnesium level"; and

5. "Getting both chelated calcium and controlled magnesium right, improves behaviour in up to 90% of difficult horses".

The ASA challenged whether the following made medicinal claims for an unlicensed product:

6. "Getting both chelated calcium and controlled magnesium right, improves behaviour in up to 90% of difficult horses"; and

7. "it can improve horse behaviour".

Investigated under CAP Code rules 3.1 (Misleading Advertising), 3.7 (Substantiation) 12.1 and 12.11 (Medicines, Medical Devices, Health-Related Products and Beauty Products)


Calinnova Ltd t/a EquiFeast stated that the overall impression of the ad was clearly that of a marketing firm that had researched the issues with their own limited resources and presented that research fairly and with no claims to having scientific substantiation. They stated that, due to the nature of the sector, their target audience was well-educated and would understand that they operated within an industry where no advertiser had the budget for peer-reviewed research. They stated that, although they had collected a large amount of evidence and had shared it with the marketplace and competitors they had never presented this information as 'science' and that the ad was therefore not misleading. EquiFeast also referred to the patent granted to them for the use of chelated calcium in horse supplements, and stated that they were therefore the only firm with the experience to present the product to the market. They asserted that in the ad they had highlighted that their theories and beliefs differed from conventional wisdom.

1. EquiFeast noted that the claim started with the phrase "Our experience," and considered that it was obvious that the claim was coming from a firm with a vested interest. They stated that readers would know that they were a small or new player in the market, and that those readers who hadn't heard of them before would be even more likely to think that they were small. In light of this, consumers would know that they would not have the resources to carry out robust research into the claim, particularly as even their larger competitors were upfront about this restriction. EquiFeast also stated that, as the claim was clearly their own experience, they did not need to prove the hypotheses with scientific data. However, they provided the following points in substantiation:

EquiFeast stated that it would be very difficult to achieve excellent sales growth without high customer retention rates, and that for this a high level of product performance is required. They noted that they had seen rapid sales growth shortly after launching both their chelated calcium calmer and a magnesium-free formula. EquiFeast stated that the Plimsoll report on the financial performance of companies in the Animal Health Industry had changed their rating from "Eye Catching" to "Strong" and that since then there had been further growth. They considered this growth was due to the addition of chelated calcium. EquiFeast also stated that competitors had responded by incorporating their name in other brands' web pages, or by adding calcium to their own formulations. They stated that two competitors had written statements condemning the use of calcium as a horse calmer, and asserted that this demonstrated that they were seen as a genuine enough threat to competitor sales as to be worth attacking.

EquiFeast described a trial for which they had provided supplements, involving five horses being given a two-month course of the product. They provided us with the abstract to this study, which they stated had been accepted as a poster at the 2014 International Society for Equitation Science in Denmark. The abstract stated that the riders had described their horses’ temperaments as significantly improved and consistently commented that their horses were more relaxed when fed the calmer. EquiFeast also provided details of a trial conducted to support their patent application. The documents stated that four groups of three to five horses that displayed agitated behaviour were given one of three chelated calcium varieties or calcium carbonate for a month, with the feeder blinded as to which was being used. A behaviour improvement mark was given to each horse by its rider and it was stated that the horses given the chelated calcium achieved somewhat higher scores than those given calcium carbonate. The trial concluded that chelated calcium calmed horses, but that non-chelated calcium did not. EquiFeast also stated that, since they had started to allow for the level of magnesium in a horse's diet before determining what supplemental level of magnesium would suffice, they had recommended many of their customers to use magnesium-free chelated calcium supplements, with good customer feedback, and that in areas where they only sold the magnesium-free product (such as Australia), their business was growing rapidly.

EquiFeast stated that since June 2009 they had kept records of all customers purchasing calmers and details of mandatory follow-up correspondence. They provided an anonymised copy of these records. They stated that the records showed 90% of their customers had positive responses, and that those using the magnesium-free formulation had a positive response rate of 93%. They stated that searching the database for "distract," "confid" or "focus" brought up several records, demonstrating that these issues were important in the effect their customers experienced. EquiFeast also noted that they sold a large amount of the product to customers who lived in areas that would have pastures rich in calcium. They considered this indicated that chelated calcium acted differently to ordinary calcium, as the type of calcium used in other supplements was limestone (such as would naturally occur in some of these areas).

EquiFeast stated that calcium was generally understood to be measured and tightly regulated by the body, and that the veterinary view was that the only form of calcium that mattered in this regard was ionised calcium (iCa). They provided data from their own blood trials and stated that these did not support that view because they showed that total blood calcium levels remained close to normal and stable throughout the trial whereas iCa was more spread out and changeable. EquiFeast stated that chelated calcium was therefore also an important form of calcium in the blood. They described another trial that suggested that when chelated calcium was given to horses with high iCa levels these levels dropped, and also showed that sometimes the levels could rise and the horse would then excrete calcium oxalate and calcium carbonate. They stated that, although this was far from conclusive, it suggested to them that chelated calcium compounds were important for calcium regulation and that excess inorganic calcium in the diet could increase the need for chelated calcium supplementation.

2. EquiFeast noted that the statement began with "According to EquiFeast's blood trials" and that they were therefore clearly not claiming that any scientifically reviewed data. They therefore considered that they were under no obligation to support the claim with 'true science' and stated that they would instead provide us with data from their blood trials. They provided this data, which included blood magnesium levels from a particular horse before and after changes to dietary magnesium were made, and comments from the horse's owner. They also provided a trial published in the June 2014 edition of the Journal of Equine Veterinary Science that, in reference to a trial conducted on foals to determine whether higher doses of magnesium given from birth could prevent particular health conditions, stated that feeding additional magnesium to foals resulted in higher magnesium in the blood.

3. EquiFeast noted that many other feed companies add magnesium to their feeds and that some specifically state it is for calming reasons. They stated that magnesium was known for its anaesthetic qualities and provided articles referencing this. They stated that magnesium sulphate and magnesium chloride had been used for years as anaesthetics in their own right, and that this use extended to horses. They provided an extract from the textbook 'The Role of Calcium and Comparable Cations in Animal Behaviour' which stated the anaesthetic effect of magnesium. The extract also suggested that the anaesthetic effects of the magnesium ion (Mg2+) could reduce painful sensations associated with use of Mg2+ to treat heartburn, and EquiFeast considered that this indicated that feeds or supplements could therefore increase the level of magnesium in the body because the doses used in calmers and antacids were similar to the doses required to treat heartburn with Mg2+. EquiFeast also noted that magnesium sulphate was banned by the FEI because of its sedative effects. They provided two videos of a rider talking about giving his horse high doses of magnesium in order to calm him and describing how, although the horse was more docile, his performance was 'flat' and unsatisfactory. EquiFeast drew particular attention to the rider's assertion that the dosed horse could not even jump a low fence. They stated that an issue they commonly encountered with riders of horses with high-magnesium diets was the horse demonstrating a 'Jekyll and Hyde' personality. They said that the horse specified in the blood trials showed this behaviour.

4. EquiFeast stated that the sentence started with a reminder to readers that the claim was their own opinion and was not scientifically proven. They said that this opinion was based on a graph of before and after blood magnesium levels of a group of horses, and provided a graph that showed the blood magnesium level of these horses altering from a wide spread of results to a narrower spread and therefore gravitating toward an ideal level. EquiFeast also stated that, since adopting a 'magnesium calculator' to determine whether customers should be recommended supplements with various levels of magnesium, they had seen the number of customers who failed to reply to requests for feedback dropping from 30% to 17%, and believed that this was because they had improved their 'right first time' rate. They reported also seeing a small improvement, from 85.8% to 89.5%, in the final success rate for those customers who agreed to 'fine tune' the balance of their supplements. EquiFeast stated that if they were not influencing blood magnesium levels then adjusting of dietary levels would have no effect on the initial success rates and that therefore, although the feedback was circumstantial evidence, it supported the inferences from the blood trials.

5. EquiFeast stated that some customers were prepared to work with them to fine tune the levels of magnesium and chelated calcium in their horse's diets. They stated that their customer service records indicated that the success rate with this group of customers was currently 89.5%. They stated that most of the horses on their trial started with magnesium levels that were inside the target range, yet still had difficult behaviour which was only corrected once chelated calcium was introduced. Moreover, they stated that those with magnesium levels outside the target range that were given chelated calcium only improved their behaviour once magnesium levels were corrected. They considered that this was strong evidence that both factors needed to be 'right' to improve behaviour.

6. & 7. EquiFeast stated that the Veterinary Medicines Directorate (VMD) had never regarded horse behaviour specifically as a medical issue. They stated that the VMD had recently looked through their website and had not asked them to remove similar claims that appeared there. EquiFeast considered that the claim "Getting both chelated calcium and controlled magnesium right, improves behaviour in up to 90% of difficult horses" constituted two parts and that the first part related only to diet and was therefore not medicinal.


The ASA noted EquiFeast's assertion that the industry was small and that research was often not carried out to the standard required by the CAP Code. We also understood that a patent had been granted and that this indicated there was little or no research being carried out on this technology by others. Nonetheless, the CAP Code requires that any claims made for the efficacy of a product must be suitably supported, and in the case of dietary supplements for animals the ASA would expect this evidence to consist of good quality trials conducted on the animals in question. Although we noted the advertiser's comments about the level of education of consumers at whom their products were aimed, we considered that these readers would still be likely to expect objective claims to be supported by robust substantiation.

1, 2, 4 & 5. Upheld

The ASA noted that four of these claims began with phrases that put them in the context of the advertiser's own experience. Nonetheless, we considered that all these references were still likely to imply to consumers that the claims in question were objective claims that were supported by robust trials carried out by the advertiser, and that they would therefore be supported by documentary evidence. Furthermore, we noted that the claims made in the ad were a departure from the widely-held view on the subject and that therefore a high degree of substantiation would be required.

We noted that EquiFeast had provided details of various trials conducted with their chelated calcium ingredients or the derivative products. However, we noted that the first trial referred to only consisted of tests on five horses and that no control, placebo or blinding method was used. The details we were provided with did not include the test data itself, such as the comments of the riders before and after the trial. We also understood that the method used to score the horses' behaviour was carried out by different riders and was therefore not consistent and controlled. Similarly we noted that, although the second trial (carried out for the patent application) did blind the feeders to which supplement they were using, the samples were still very small and no comparative data about the horses' behaviour before and after the trial, nor any indication of the significance of the data, was provided. With regard to the blood trial data, we noted again that the sample sizes were small and that we were provided only with the results and not with the background data on the horses, such as diet or location, or the rationale for the target nutrient levels described in these trials. Finally, we noted that the trial published in JEVS related only to foals that had been given additional magnesium from birth, rather than adult horses that had been subsequently introduced to the supplement. We noted that there was no baseline data for the foals' blood magnesium levels before supplementation, or information about significance levels. We therefore considered that the trials provided to us were not sufficient to substantiate the claims made in the ad.

In relation to the first claim, we noted that EquiFeast had provided the market expansion as evidence for the product's efficacy. While we recognised that the company had seen growth during the period in which the product was sold, we considered that this was inadequate to demonstrate that the product was effective. We also appreciated that EquiFeast had received a large amount of positive customer feedback. However, we considered that this amounted to anecdotal evidence for the product's effects, rather than a robust, variable-controlled trial. Similarly, although we understood that customer response rates had gone up since the introduction of the magnesium calculation approach, we did not consider that this was sufficient to substantiate a claim regarding the ability of horses to regulate their blood magnesium level. Because EquiFeast had not provided evidence to support their claims, we concluded that the ad breached the Code.

The ad breached CAP Code (Edition 12) rules  3.1 3.1 Marketing communications must not materially mislead or be likely to do so.  (Misleading Advertising) and  3.7 3.7 Before distributing or submitting a marketing communication for publication, marketers must hold documentary evidence to prove claims that consumers are likely to regard as objective and that are capable of objective substantiation. The ASA may regard claims as misleading in the absence of adequate substantiation.  (Substantiation).

3. Upheld

The ASA understood that some magnesium compounds could have a sedative effect and that the rider in the video ascribed the unsatisfactory performance and changed behaviour of his horse to these effects. We noted the advertiser's assertion that customers who fed their horses high amounts of magnesium reported changeable behaviour. However, we had not seen evidence to demonstrate that a surfeit of magnesium would be responsible for these behaviour patterns, and therefore concluded that the ad breached the Code.

The ad breached CAP Code (Edition 12) rules  3.1 3.1 Marketing communications must not materially mislead or be likely to do so.  (Misleading Advertising) and  3.7 3.7 Before distributing or submitting a marketing communication for publication, marketers must hold documentary evidence to prove claims that consumers are likely to regard as objective and that are capable of objective substantiation. The ASA may regard claims as misleading in the absence of adequate substantiation.  (Substantiation).

6. & 7. Upheld

The ASA took advice from the VMD. We understood claims about behaviour improvement in horses would be considered to be medicinal if they referred to a nutrient deficiency. We understood that the claims made in the ad had not been part of the VMD's assessment of the advertiser's website. We noted that the ad clearly referred to the level of calcium and magnesium in a horse's diet and blood, and linked this to poor behaviour. We considered that consumers would be likely to infer from this that the product could treat behavioural problems caused by a nutrient deficiency, and that the ad was therefore making medicinal claims for an unlicensed product.

The ad breached CAP Code (Edition 12) rules  12.1 12.1 Objective claims must be backed by evidence, if relevant consisting of trials conducted on people. Substantiation will be assessed on the basis of the available scientific knowledge.
Medicinal or medical claims and indications may be made for a medicinal product that is licensed by the MHRA, VMD or under the auspices of the EMA, or for a CE-marked medical device. A medicinal claim is a claim that a product or its constituent(s) can be used with a view to making a medical diagnosis or can treat or prevent disease, including an injury, ailment or adverse condition, whether of body or mind, in human beings.
Secondary medicinal claims made for cosmetic products as defined in the appropriate European legislation must be backed by evidence. These are limited to any preventative action of the product and may not include claims to treat disease.
 and  12.11 12.11 Medicines must have a licence from the MHRA, VMD or under the auspices of the EMA before they are marketed. Marketing communications for medicines must conform with the licence and the product's summary of product characteristics. For the avoidance of doubt, by conforming with the product's indicated use, a marketing communication would not breach rule 12.2.
Marketing communications must not suggest that a product is "special" or "different" because it has been granted a licence by the MHRA, VMD or under the auspices of the EMA.
 (Medicines, Medical Devices, Health-Related Products and Beauty Products).


The ad must not appear again in its current form. We told Calinnova Ltd to ensure that in future they held robust documentary evidence for their efficacy claims and that future ads did not contain medicinal claims for unlicensed products.

CAP Code (Edition 12)

12.1     12.11     3.1     3.7    

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