This article has not yet been professionally approved. The information is based on the sources listed below.
Rose hips for horses: vitamin C and what is proven
What rose hips provide for horses, why horses produce vitamin C themselves, how much the content varies and how thin the evidence in horses is.
The short answer
Rose hips mainly provide horses with vitamin C, but horses produce vitamin C themselves in the liver 1. The content of the fruit varies widely depending on variety, location and harvest time 2. The few horse studies come from an industry-linked research group. Rose hips are therefore a feed addition without proven additional benefit. Before competitions, check them in the ADMR database 3.
What rose hips contain
Rose hips are the fruit of the dog rose (Rosa canina). They are known for their vitamin C. How much they contain depends heavily on species, variety, altitude and harvest time; the literature gives 106 to 2,712 mg per 100 g 2.
- Rose hips also contain the fat molecule GOPO. Its effect has so far only been studied in the laboratory on human cells 4.
- Some compounds are sensitive to heat, and processing can reduce them 4.
| Part of the fruit | Vitamin C per 100 g |
|---|---|
| Whole fruit | 411 mg |
| Flesh | 2,200 mg |
| Seeds | 306 mg |
Vitamin C in Rosa canina from one study; the source does not state whether fresh or dry matter is meant 2.
Does the horse need vitamin C?
The horse produces vitamin C itself in the liver 1. A healthy horse therefore does not depend on vitamin C from feed.
Whether certain horses, such as very old or sick ones, benefit from extra vitamin C is not proven by the sources reviewed here.
What has been studied in horses
In one study, 16 trotters received 25 or 50 g of rose hip powder daily for 84 days. Vitamin C in the blood only rose clearly in the 50 g group. There was no group without rose hips 5.
Feeding rose hips and competitions
Rose hips are a feed. Include the daily amount in the ration like any other feed, especially with powders and mixes.
Vitamin C and rose hip are not on the 2025 FEI list 6. In German competitive sport, however, the FN (German Equestrian Federation) bans phytotherapeutics in general 7. So check rose hips and mixes containing rose hips in the ADMR database 3.
Key takeaways
Frequently asked questions
How many rose hips can a horse have?
There is no proven daily amount. In the only horse study on vitamin C, trotters received 25 or 50 g of rose hip powder daily 5. Include rose hips in the ration like any other feed.
Do rose hips help with joint problems?
This has not been independently proven. The compound GOPO has so far only been studied in the laboratory on human cells 4. Joint problems should be investigated by your vet.
Do older horses need extra vitamin C?
In principle, horses produce vitamin C themselves 1. Whether older horses need extra is not proven by the sources reviewed. If your horse is ill, discuss this with your vet.
Sources & studies
The content is based on the references listed below. It does not replace individual veterinary or feeding advice.
Show list of sources (7)
- Merck Veterinary Manual: Nutritional Requirements of Horses and Other EquidsSummary of the NRC recommendations: water requirement 5 litres per 100 kg body mass per day at maintenance, sweat losses of around 3.1 g sodium, 5.3 g chloride and 1.6 g potassium per litre, salt recommendation 1.6–1.8 g per kg feed dry matter at a maximum of 6% of the ration; from a 50% forage share potassium is adequately covered. Also covers the selenium requirement (0.1 mg/kg feed dry matter or at least 1 mg/day for a 500 kg horse, selenium as a component of glutathione peroxidase together with vitamin E) and the strong location-dependent variation of selenium in forage (grass forage on average 0.194 ppm, range 0–1.2 ppm); some regions are markedly low in selenium and may need supplementation. Also gives the iodine requirement (0.35 mg/kg feed dry matter, mares in late pregnancy 0.4), iodine poisoning of pregnant mares from around 40 mg/day, documented goitre cases in mares and their foals associated with large amounts of dried seaweed (kelp), that iodised salt easily covers the requirement, and that iodine supplementation is usually unnecessary except in severely iodine-deficient regions
- Kazaz S, Baydar H, Erbas S (2009): Variations in chemical compositions of Rosa damascena Mill. and Rosa canina L. fruits. Czech Journal of Food Sciences 27(3):178–184Rosa canina: ascorbic acid 411 mg/100 g in the whole fruit, 2,200 mg/100 g in the flesh, 306 mg/100 g in the seeds (Table 2; fresh or dry matter basis not stated). According to cited literature 106–2,712 mg/100 g depending on species, variety, altitude and harvest time
- FN – Anti-Doping und Medikation (ADMR-Suchmaschine)Official database of the FN (German Equestrian Federation) on substances and withdrawal periods in competitive sport
- Winther K, Vinther Hansen AS, Campbell-Tofte J (2016): Bioactive ingredients of rose hips (Rosa canina L) with special reference to antioxidative and anti-inflammatory properties: in vitro studies. Botanics: Targets and Therapy 6:11–23Overview of in vitro data. The galactolipid GOPO was isolated from Rosa canina by Larsen et al. and inhibited the chemotaxis of human immune cells in vitro; according to Schwager et al. it is found mainly in the shells. Some constituents are heat-labile. Conflict of interest: K. Winther was a consultant to Hyben Vital for animal products. No horse studies
- Winther K, Kharazmi A, Hansen ASV, Falk-Rønne J (2012): The absorption of natural vitamin C in horses and anti-oxidative capacity: a randomised, controlled study on trotters during a three-month intervention period. Comparative Exercise Physiology 8(3–4):195–20116 Standardbred trotters, 84 days of 25 g (approx. 125 mg vitamin C) or 50 g (approx. 250 mg) rosehip powder daily. Serum vitamin C significantly raised only at 50 g (from day 14), plus lower release of oxidative anions from leucocytes. No placebo without rosehip (two dose groups). The first author was a consultant to the manufacturer Hyben Vital (see Winther 2016)
- FEI (2024): 2025 Equine Prohibited Substances List. Fédération Équestre Internationale, Lausanne, Stand 25.11.2024Version checked: 2025 (the 2026 version could not be accessed on 18 October 2026). Harpagoside is listed as CONTROLLED (analgesic), valerenic acid as CONTROLLED, capsaicin as BANNED. Silibinin/silymarin, Vitex constituents (agnuside, casticin), nettle, rosehip and ascorbic acid are not listed by name. Catch-all clause: substances with a similar chemical structure or similar biological effect are also prohibited. The list is revised annually; the current version always applies
- Deutsche Reiterliche Vereinigung (FN): Anti-Doping- und Medikamentenkontroll-Regeln für den Pferdesport (ADMR) mit Verbotsliste Anhang I–IIIRulebook with its own FN prohibited list (Art. 4.1). Annex II (prohibited medication, banned in competition) explicitly names “Harpagophytum Procumbens (Teufelskralle)” (devil's claw) under the musculoskeletal system and, under “Darüber hinaus sind verboten” (also prohibited), lists in general terms “Phytotherapeutika, wie z.B. Arnika, Ingwer” (phytotherapeutics such as arnica, ginger). Catch-all clause for substances with a similar structure or effect. Responsible persons are personally liable for everything administered to the horse (Art. 2.1.1), including with contaminated feed supplements (commentary on Art. 10.4). The document bears no date