Choosing a horse supplement is harder than it should be. Products with similar names can contain very different ingredients, claims are often vague and prices are hard to compare across pack sizes and feeding rates. This guide sets out a practical method: start with a clear need, read the label properly, work out cost per day, question the evidence, check competition status and look out for marketing red flags. It is the same approach we use in our desk reviews, described in full on our how we review page.
Start with the need, not the product
Before comparing anything, write down what you want the supplement to do and why. A reason such as "my horse is changing from haylage to hay next month" is much easier to act on than "general gut health". Then check whether management could address the need first: forage quantity and quality, gradual changes to diet and turnout, water and routine. Many problems owners hope to solve with a supplement start with one of these.
Next, check what the existing diet already supplies. A feed balancer or fortified compound feed may already include vitamins, minerals, live yeast or prebiotics, and adding another product can mean paying twice for the same ingredients, or oversupplying. Our guide to vitamins and minerals explains how to add up a ration.
Reading a UK supplement label
The British Equestrian Trade Association (BETA) explains that, legally, there is no such thing as a supplement: products sold as supplements are feeds, and their labels must follow the same rules as other feeds under retained Regulation (EC) No 767/2009. Most are labelled "complementary feed"; a single-ingredient product is a "feed material", and a product with more than 40% ash (minerals) is a "mineral feed".
Composition
The main ingredients are feed materials, listed under "Composition" in descending order of inclusion, with the largest first. Manufacturers do not have to state how much of each feed material is included, which protects their recipes but means you cannot always tell how much of a named ingredient is present. An ingredient listed near the end of a long composition list may be present only in a small amount.
Additives and inclusion levels
Technical ingredients such as vitamins, trace minerals, live yeast and some prebiotics are listed under "Additives". BETA explains that additives must come from an approved register and that many carry an identification number, such as 3a300 for vitamin C or 3b606 for chelated zinc. Unlike feed materials, additives should show an inclusion rate, usually per kilogram. Under Annex VII of the regulation, zootechnical additives, which include live yeast authorised as a digestibility enhancer, must be listed by name or identification number with the amount added and their functional group.
This is where the useful numbers are. Multiply the amount per kilogram by the daily feeding rate to find what your horse receives each day. For a probiotic, that might be a count of colony forming units (CFU); for a vitamin and mineral product, milligrams of copper or zinc.
Analytical constituents
This section gives nutrient levels such as crude protein, crude fat, crude fibre, crude ash and sodium. BETA points out that sugar and starch need not be listed unless a claim is made about them, and that at typical supplement feeding rates these figures usually have little effect on the overall diet.
Directions and traceability
The label should include feeding instructions, a batch number, a best before date, the species the product is intended for, storage guidance and the manufacturer's details. BETA also cautions that products bought online from outside the UK may not comply with UK feed law and may be labelled very differently.
The cost per day method
Tub price tells you very little, because pack sizes and feeding rates vary so much. Cost per day puts products on the same footing.
- Find the daily feeding rate for your horse's bodyweight on the label, in grams.
- Divide the pack weight in grams by the daily rate to find how many days the pack lasts.
- Divide the price by that number of days.
A 3 kg tub fed at 30 g a day, for example, lasts 100 days, so its cost per day is the price divided by 100. Use the full maintenance rate, not a reduced one, and account for any loading period. Then go one step further and compare cost per unit of active ingredient, such as cost per billion CFU of live yeast. A cheaper product that delivers a fraction of the active ingredient is not better value. Our comparisons use this method throughout.
Evidence questions to ask
Good evidence for an ingredient does not automatically mean good evidence for a product. These questions help separate the two.
- What is the active ingredient, and how much is in the daily dose? If the manufacturer cannot say, that is informative in itself.
- Has it been studied in horses? Research in people, other animals or laboratory systems may not translate.
- At what dose, and in which horses? A study in racehorses on high-starch diets may not apply to a native pony at grass.
- Was it published and peer reviewed? Conference abstracts and in-house trials are a weaker basis than published, controlled studies.
- Who funded it? Industry funding is common and does not invalidate a study, but it should be declared and weighed.
- What did independent reviews conclude? For probiotics, reviews describe the evidence as mixed or weak for many uses, as our guide to equine probiotics explains.
BETA NOPS and competition
If you compete under rules, contamination is a real concern. BETA set up its NOPS scheme in 2009 to reduce the risk of naturally occurring and other prohibited substances in feed. Accredited companies must assess contamination risk at every stage from sourcing to finished product and are audited by BETA. BETA notes that both the British Horseracing Authority and the FEI apply a no-threshold policy for naturally occurring substances that could affect performance, with theobromine the exception.
- The scheme operates at company level, so all products placed on the market by an accredited company are covered.
- A product made in a NOPS-accredited plant does not mean the company marketing it is accredited.
- Use BETA's online webchecker to confirm a company's status.
- Products that intentionally contain low-priority herbal ingredients may not carry the NOPS logo and are limited to horses not competing.
The scheme reduces risk but cannot remove it, so always check your governing body's rules and keep records of what you feed. Our page on travel and competition covers wider competition management.
Red flags in marketing claims
The Veterinary Medicines Directorate (VMD) publishes guidance on advertising non-medicinal veterinary products, which covers feeds and supplements. Non-medicinal products may only be presented as maintaining health in healthy animals. Claims that a product treats or prevents disease, restores or corrects a dysfunction, or has an antibacterial or antiviral effect are medicinal claims. The guidance notes that wording such as "may help treat" still counts as a medicinal claim, and that a disclaimer does not cure one.
Be cautious when you see:
- claims to treat, heal, cure or prevent named conditions such as ulcers, colic or laminitis;
- product names that echo a disease;
- before and after photographs of a health condition;
- presentation as a natural alternative to a licensed medicine;
- "natural" used to imply "safe" or "competition legal";
- no strain, no inclusion levels and no clear feeding rate;
- testimonials offered in place of evidence.
Look instead for quality marks that indicate independent audits. BETA mentions UFAS (Universal Feed Assurance Scheme) in the UK and GMP+ on more global products.
Talking to your vet or a registered nutritionist
A short conversation can save money and prevent problems. Your vet should be involved whenever a supplement is being considered because of a health concern, and a qualified nutritionist can review the whole ration. World Horse Welfare suggests finding qualified equine nutritionists through feed companies, the Association for Nutrition register or the Equine Nutritionist and Feed Advisor register. Take your label photographs, a note of how much forage and feed your horse receives, its weight and condition and what you hope the product will achieve.
When you are ready to compare specific products, our UK probiotic comparison applies these questions to the main options.