How Scent Affects a Horse's Wellbeing

April 2, 2025

A horse in a stable, illustrating how scent affects equine wellbeing

How Scent Affects a Horse's Wellbeing

One of the more interesting subjects we are currently digging into at LISS Products is the influence of scent on equine wellbeing. In this piece I want to take you through what we have learned about the relationship between smell and emotion in horses.

Just as in people, scent can influence emotion and overall mood. Horses have an exceptionally well developed sense of smell, far more sensitive than ours, which means odours can carry considerably more meaning for them than they do for us. Below we work through the questions we get asked most often, and explain why it is worth understanding which smells your horse finds pleasant and which he does not.

Do certain smells influence a horse's emotions and mood, the way they do in people?

Yes. Horses use their sense of smell to make sense of their surroundings, to communicate with other horses, and to detect threats. Smells that are familiar can be reassuring and calming. Unfamiliar smells, or smells associated with danger, can cause stress or fear.

Scent plays a real role in emotional wellbeing. The smell of familiar horses or of a familiar environment tends to have a settling effect, while stressful smells, such as those of unknown animals or an unfamiliar yard, can provoke anxiety.

Can a smell make a horse happier?

Scent can contribute to a horse's comfort and wellbeing. When a horse smells something he associates with positive experiences, such as his owner or horses he knows well, it can produce a sense of safety and calm. That matters most in stressful situations: during transport, in a new environment, or in the build-up to a competition.

Natural scents such as lavender, chamomile and eucalyptus have a reputation for calming effects. Research into how specific scents affect horses is still developing, but work in other species suggests aromatic plants can positively influence mood and behaviour. Used thoughtfully, scent may well contribute to a calmer, more settled horse.

If their sense of smell is stronger than ours, when is a scent too strong for a horse?

A horse's olfactory system is substantially larger and more sensitive than a human's. What seems mild or subtle to us can be far more intense to a horse. A fragrance we find pleasant may be overwhelming to him, which can lead to discomfort or stress.

When a scent is too strong, a horse may shake his head, avoid certain areas, or become noticeably more nervous. Scent should therefore be applied subtly and in a controlled way, so it does not overwhelm. Fragrances that are sharp or obviously artificial can work against a horse's wellbeing rather than for it.

Can horses be irritated or overwhelmed by certain smells?

Yes. Because a horse's sense of smell is so acute, some odours are far more intense for him than for us. That can cause stress or discomfort, particularly where the fragrance is synthetic or sharp. Artificial scents are often the worst offenders, because they read as intense and unnatural to a horse.

A horse repeatedly exposed to a smell he finds unpleasant may withdraw or show changes in behaviour. That unsettles him, and it can affect his performance, his wellbeing and his general mood.

Can you use scented products before a competition, or does that count as doping?

This is the question where the answer is more complicated than most people expect, and it is worth reading carefully.

The FEI position is unambiguous: any substance that affects a horse's performance in a calming or energising manner and contains a Prohibited Substance is forbidden. The FEI also warns explicitly against herbal and natural products whose ingredients and quantitative analysis are not fully known, and it does not test or approve such products.

Crucially, being plant-derived offers no protection. Several of the botanicals most associated with calming horses are on the prohibited lists, including valerian, and both chamomile and lavender are prohibited in FEI and USEF competition. A product marketed as natural can still produce a positive test.

So the honest answer is this. A grooming or care product used for cleaning and conditioning, with no pharmacologically active calming ingredient, is not doping. But the moment a product is intended to calm the horse, or contains a botanical on the prohibited list, you are in regulated territory, and responsibility sits with the rider.

If you compete, check the ingredients of anything you use against the current FEI Equine Prohibited Substances List, and speak to your vet if you are unsure. Do not rely on a manufacturer's claim that a product is natural and therefore safe.

What about artificial fragrances?

Synthetic fragrances are common in commercial products and are usually cheaper than natural ones. They are built from synthetic chemicals that imitate the smell of natural substances. A product can therefore appear to contain lavender, and sound natural as a result, while what has actually been added is a synthetic lavender note. That does not make the product natural.

Artificial fragrances can also be too intense, unnatural, and in some cases harmful to people and animals alike. Prolonged exposure can contribute to allergic reactions, respiratory problems or skin irritation in horses.

There is a further problem. Horses use scent to gather information about their environment, about other horses and about potential threats. Artificial fragrances can interfere with that, causing confusion and putting the horse into a stressful situation. It is one reason there is growing appreciation for products built on natural scent profiles that support rather than disrupt the animal.

Are natural scents better for horses?

Natural aromatics such as lavender, chamomile and eucalyptus carry the complex aroma profiles found in nature, and are often associated with calming, settling properties. Because they are subtler and less obviously chemical, they sit more comfortably with a horse's senses.

They are also generally milder and gentler, which reduces the risk of irritation or overstimulation. Used well, natural scent can contribute to a calmer and more comfortable horse.

The caveat from the competition section still applies: milder does not mean permitted. Natural and competition-legal are two different questions.

In closing

Scent plays a genuine role in equine wellbeing. Because a horse's sense of smell is so highly developed, odours can affect mood and behaviour in both directions. Natural scents have real potential to calm and reassure; artificial ones are frequently too intense, and sometimes actively unhelpful.

It is worth thinking carefully about which smells you introduce into your horse's environment. Choosing natural, subtle scent profiles is a small decision that can make a horse more comfortable in his own surroundings.

We are busy behind the scenes developing new products, and we want to account for everything that contributes to a horse's overall wellbeing. Scent has a central place in that work.