Essential Oils

What are essential oils?

An essential oil is the natural fragrant essence extracted from flowers, leaves, bark, roots, fruit peel and berries. The most concentrated and potent of plant extracts, essential oils are approximately 75-100 times more concentrated than dried herbs, which is why such low concentrations are used in massage and skincare.

Often referred to as the soul of the plant, an essential oil contains the life force of the plant from which it comes, and is part of the plant’s immune system; the plant produces more essence when under stress.

A single essential oil is made up of hundreds of different chemical constituents, with each individual constituent bringing its own set of properties to the oil, resulting in a highly complex substance.

European manufacturers of skincare products containing essential oils are required to list some of these constituents on the labels of their products – you can see these listed in italics on our skincare labels – these are naturally occurring and not added to the product.

The chemical constituents of an essential oil generally occur as a combination of major, minor and trace elements, some of which are present in such minute quantities that they can’t be analyzed. This complexity is the reason why most essential oils can’t be recreated synthetically; the subtlety of these trace constituents is missing.

An example of a major constituent is menthol, which makes up about 40% of peppermint oil, and gives the oil its characteristic properties and aroma. Some constituents are so strong-smelling that even if they are not a major component of the oil, they contribute greatly to the aroma.

The constituents of essential oils vary widely, from crop to crop and season to season, which is why it’s not possible to have a ‘standard’ for an essential oil. With more than 40 years of experience in sourcing and selling essential oils, we have an incredible understanding of the complexities and vagaries of essential oils. For example, lavender grows just about everywhere in the world – we even have it in our own back yards. If we distilled lavender essential oil from our backyard plants, it would have a very different profile (and therapeutic activity) from lavender oil distilled from plants grown in Provence, in the south of France, or Hampshire in the south of England. Provence, for example, is around 3000 ft above sea level, the climate and soil conditions are perfect for growing lavender that produces an essential oil with the ideal combination of constituents to give us the therapeutic properties we are looking for.

Wherever possible we choose essential oils certified organic by the UK's Soil Association, as this ensures that cultivation is managed under the highest possible, independently-audited ethical and environmental standards, and that the plants are grown free from synthetic chemical herbicides and insecticides. The Soil Association is widely regarded as one of the world’s strictest organic certification bodies. For the essential oils that aren’t organic, wherever possible they’re wild-crafted, grown in their natural habitat. In addition to this, we actively support fair trade and the ethical, sustainable sourcing of ingredients.

How are essential oils produced?

Steam Distilled

One of the most common and popular ways of extracting essential oil is through steam distillation, which is especially suitable for robust plants such as lavender. The plant material is placed in a still or container and pressurized steam is passed through it. The steam causes the plant matter to release its precious essential oils. These are carried away in the steam, which is then cooled, leaving a pure essential oil and distilled plant water – as oil and water don’t mix.

Absolute extraction

The essence of delicate flowers such as jasmine and rose which are too fragile (or cost prohibitive due to low yields) to be steam-distilled, are solvent extracted. The solvent is mixed with the plant material to draw out the precious essence and waxes to form a concrete. The concrete is then washed with ethanol to separate out the fragrant molecules from the plant waxes. The ethanol is then evaporated off to leave the absolute.


For citrus fruits like lemon and grapefruit, the essential oils are expressed. This simply means the peel is pressed to release the essential oil.

How should essential oils be applied to the skin?

As essential oils are highly concentrated, they need to be blended into a carrier oil, lotion, bath oil or shower gel before being used on the skin.


Massage is a wonderful way to ease aching muscles and relax or energize the body.
Place the required quantity of massage base, such as almond oil or a lotion, into a saucer (a typical full body massage uses 2tbsp of base product) then add the drops of essential oil(s) based on the required effects of the massage and stir thoroughly.

See the table below for guidance. Be careful not to exceed the recommended total number of drops.

Baths & showers:

Bathing with pure essential oils is one of the most luxurious ways to enjoy their benefits; the essential oils are inhaled through the aromatic steam, as well as being beneficial for the skin. Add the recommended drops of essential oil to the base oil, bath oil or shower gel, then add to a full bath (don’t add to running water). Try to stay in the bath for 15 minutes (not normally too difficult) to really benefit from the essential oil’s properties.

Soto Aroma Diffuser


Essential oils make fantastic natural air fresheners, fragrancing a room as well as setting a mood. Simply add a few drops of your chosen essential oils to a diffuser or vaporizer, always making sure to follow the manufacturer’s instructions.


Help clear the head and nose with 4-6 drops of essential oil added to a bowl of steaming water. Place a towel over your head and lean over the bowl – creating a tent effect to trap the steam – and inhale the vapor for a few minutes. NOTE: Not suitable for children or those with asthma – instead place a bowl of hot water with added essential oils nearby.

Blending Table
Amount of base oil/lotion/bath oil/shower gel 10ml 20ml 25ml 30ml 50ml
  1 tbsp 2 tbsp 2.5 tbsp 3 tbsp 5 tbsp
Maximum number of essential oil drops          
Children over 2 years, adults with delicate skin or applying to face 2 4 5 6 10
Adults with no skin sensitivities 5 10 12 15 25

How do essential oils benefit us?

Our sense of smell is one of our most powerful yet under-used senses; researchers have revealed that we respond strongly to smell in the limbic brain, the part that deals with emotions and memories.

This explains why certain smells can trigger powerful emotions or physical reactions – such as becoming more relaxed or being able to sleep. Alongside the emotional response, essential oils are often very beneficial for the skin.

Can essential oils be taken internally?

At Neal’s Yard Remedies we don’t advise taking essential oils internally. We are a member of the UK’s Aromatherapy Trade Council (ATC), and their safety guidelines also advise against the internal use of essential oils. Even certified aromatherapists aren’t allowed to recommend their use this way.

If essential oils are taken internally, apart from the potential for irritation of the sensitive mucosal lining of the gut, the entire dose is released at once into the bloodstream, and then to the liver. MedLine lists the toxic dose of eucalyptus oil as just 3.5ml (less than one teaspoon) if taken internally. Application to the skin, as described above, is much more suitable because the skin acts as a kind of time-release system so that the constituents of the oils are released gradually.

How can some essential oils be listed as both relaxing and stimulating?

Many essential oils such as lavender, marjoram and eucalyptus have what is known as a balancing effect. They tend to bring you back to a ‘median’ point at which you normally function. For instance, if your energy is low the essential oil may invigorate you, bringing you back to a normal state. If your energy is high, the same oils may calm you. The amount of essential oil used is also important. A few drops might be calming, but using more can be stimulating.

Why is there such a variation in the cost of essential oils?

The concentration of essential oils in the plant and the process of distillation dictate the price.
For instance, eucalyptus is quite inexpensive (an abundance of oil is found in the leaves and distillation is easy) and rose is very expensive (there’s very little oil in the flower and it’s quite costly to process). It takes approximately 3000 organic roses to make just 0.08 fl.oz of exquisite Rose Otto essential oil.

Other factors that affect the cost are the ease of distillation, modern vs. traditional equipment, climate and world demand. The essential oil of Melissa (lemon balm) is very expensive, despite it growing abundantly, as it’s difficult to extract.

What is the shelf life of essential oils and how should they be stored?

Essential oils don't really expire. The optimum shelf life of an essential oil is approximately 1-3 years, with citrus oils lasting about a year, and resinous oils such as frankincense lasting 2-3 years. After this time, while the aroma may still be good, the oil will have lost some of its potency and therapeutic effects, as the individual constituents start to evaporate. They don't go ‘bad’ or ‘rancid’.

Labeling essential oils

As with skincare labeling, the information we are required to put on our essential oil labels is specified by law in Europe.

These laws include a requirement to put a batch number on our oils; we also specify the botanical name, the part of the plant used, and the method of extraction. However, Essential oils are sensitive to UV light, heat, and oxygen, so should be stored in a cool, dark cupboard, with the tops secured tightly. The labelling laws also require that oils are labelled ‘for external use only’.

How do essential oils differ in quality?

Essential oils can differ in quality depending upon several factors. How was the plant grown, is it organic? How has it been handled? How skilled was the farmer? What type of equipment was used? Was the right amount of steam and pressure used in its distillation? Have solvents been used in the distillation process? Has the plant been distilled for the correct amount of time? (The requirements for each plant vary.)

The experienced aromatherapist will be able to tell a lot just by smelling the oil. The same species of plant grown in different countries under different soil and altitude conditions will produce oils that differ in their therapeutic properties.

Neal’s Yard Remedies uses ‘single species’ essential oils. We do not blend oils from similar species. Some companies add essential oils to enhance the fragrance of a cheap or synthetic oil, so it’s always important to buy from a company that has experience of sourcing and selling pure essential oils.

Essential Oil ‘standards’

In the absence of any internationally recognized standards for essential oils, some companies have created their own standards, however these don’t really have any meaning beyond the individual company.

Being certified by an independent, internationally recognized organic certification body like the UK’s Soil Association guarantees that our organic essential oils are grown free from synthetic chemical herbicides and insecticides, and independently audited to ensure they are produced to recognized organic standards.

Essential oil blends

When you mix something together and the combination is more than the sum of the parts, there is a synergistic effect. By mixing together two or more essential oils, you are creating a blend that is different to the component parts. An increased potency can be achieved with synergistic blends without increasing the dosage. For example, the soothing action of chamomile essential oil is greatly increased by adding lavender in the correct proportion.

Neal’s Yard Remedies Aromatherapy Blends are created by qualified aromatherapists, and are a fantastic way for customers new to aromatherapy to experience the wonderful benefits of blending essential oils.

Essential oils in household products

Many household products now list ‘essential oils’ as ingredients. Essential oils used in this way, lemon and pine for instance, are usually synthesized in a laboratory, so they may smell like the real essential oil, but will have none of the therapeutic properties of the true oil.

It is simply not cost-effective for the manufacturers of detergents to use pure essential oils. The downside is that people who have experienced these ‘synthetic’ versions of an essential oil, and didn’t care for the smell, probably don’t realize how different the true oil really is.

Pioneers of essential oils from day one

When the first Neal’s Yard Remedies store opened back in 1981, in Neal’s Yard, London, we sold pure essential oils, herbs, and homoeopathic remedies. In fact we were the first main street retailer in the UK to sell certified organic essential oils. Today, essential oils are still very much at the heart of our business, both as pure single Essential Oils and Aromatherapy Blends, and in our skincare, where they are selected for their beneficial effects on the skin and emotions.

Like any company serious about the quality of their oils we include the following information on our labels:

Common name
Botanical name
Part of plant used (flower, leaf, berry, peel etc.)
Country of origin
Method of extraction
Batch number

We believe that one of the key factors in ensuring consistently high quality essential oils is building strong relationships with our suppliers. We have worked with some of our suppliers for decades, and buy the entire crop of many of the growers we work with (for example: lavender, frankincense, neroli).

A final note – there are some good companies selling nice quality oils, however there are not many that have the experience that we do. The supplier relationships and experience with quality that we have accumulated over more than 40 years is pretty much unsurpassed.


Neal’s Yard Remedies Essential Oils, Susan Curtis, especially pp.138-139
Aromatherapy: An A-Z, Patricia Davis
Fragrant Pharmacy, Valerie Worwood