What Are Essential Oils and How and Why Do They Work?

Essential oils are used in natural medicine because of their physical and mental health properties. Today, we'll take a look at their main uses.
What Are Essential Oils and How and Why Do They Work?
Franciele Rohor de Souza

Reviewed and approved by the pharmacist Franciele Rohor de Souza.

Last update: 28 July, 2022

Have you ever wondered what essential oils are? Since ancient times, essential oils have been present in many cultures around the world. There are records that suggest their application in ancient Egypt, so it’s estimated that they’ve been used since 3,500 years B.C.

In general, they’re valued for their aromatic power and their interesting medicinal properties. Due to their composition, they’re often used as adjuvants to reduce stress, soothe ailments, and reduce the risk of infections, among other things.

Of course, like many natural products, you should use them with caution and in moderation. While it’s true that their properties benefit health, they’re not free of contraindications and unwanted effects. In the following article, we’ll tell you what they’re used for and which are the most recommended.

What are essential oils?

It’s likely that you’ve wondered what essential oils are. These ingredients have been used in natural medicine for thousands of years. In particular, they’re volatile essences that are extracted from aromatic trees and plants through a process of distillation or cold pressing.

They shouldn’t be confused with commercial oils that are obtained through chemical methods, as their composition is different. Often, the pure essential oil is combined with a carrier oil to make it suitable for use.

As discussed in an article reported in Evidence-Based Complementary and Alternative Medicine, essential oils are often used as disinfectant allies and stimulants. They have also been found to act as anti-inflammatories, analgesics, antimicrobials, and pain relievers.

We think you may also enjoy reading this article: Bergamot Essential Oil: Benefits and Possible Side Effects

How and why do essential oils work?

Essential oils are not suitable for consumption; their properties are used through inhalation or applied topically (combined with a carrier oil). According to research shared in the International Journal of Molecular Sciences, three possible mechanisms explain their effects.

The first involves the activation of nasal olfactory chemoreceptors which then send olfactory signals to the brain. Specifically, they effects the limbic system this way, which is a brain region involved in the regulation of emotions, behaviors, and long-term memory.

The other two possible mechanisms involve the direct penetration of their molecules through the olfactory nerve into brain areas and the alveolar absorption of their compounds into the bloodstream, which appear to cross the blood-brain barrier to generate the stimulus.

However, when applied to the skin, phytochemicals that are beneficial to health are absorbed. In this regard, research in Pharmazie states that there’s no doubt that the components of oils can penetrate human skin.

Aceite esencial para colocar en la piel.
Essential oils can be placed on the skin so that they penetrate it and their molecules then act.

The main properties of essential oils

The effects of essential oils vary depending on the plant of origin and the extraction process used during their production. However, on a general level, they’re characterized by the following properties:

  • Antiviral
  • Antibiotic
  • Antimicrobial
  • Anti-inflammatory
  • Regenerating and healing
  • Antioxidants
  • Adaptogenic
  • Sedative

In most cases, these effects are exploited in aromatherapy sessions. Inhalation of the products stimulates respiration, cell regeneration, the nervous system, and blood circulation. Thus, it generates a feeling of physical and mental well-being.

The most commonly used essential oils

It’s estimated that there are more than 90 varieties of essential oils. Most of them are used in aromatherapy, but also in cosmetics and in the food industry.

Here are the most commonly used and their general properties:

Recommendations for choosing essential oils

There are several aspects to consider when purchasing essential oils. Right now, many stores sell various presentations that are not always of the best quality.

Some are not pure and come mixed with other oils. And while they may have pleasant aromas, they don’tt produce the desired effects.

Therefore, it’s worth bearing in mind the following:

  • Choose high purity oils: They usually have the botanical name of the plant on the label. They don’t contain any additives.
  • Verify the extraction process: Is it distillation or cold pressing? If it involves other procedures, the essential oil is probably not pure.
  • Choose a trusted brand: Some have a long history as manufacturers.
Comprar aceites esenciales.
When buying an essential oil, the process by which it was obtained should be checked to ensure its purity.

The risks and side effects of essential oils

Just because a product is natural does not mean it’s safe.

Essential oils are no exception. In fact, misuse can lead to various side effects ranging from mild to serious. The most common are the following:

  • Eruptions
  • Photosensitivity
  • Headaches
  • Breathing difficulties

As with their beneficial properties, these reactions vary according to the composition of each type of oil. In any case, caution is recommended in special cases:

  • Infants and children
  • Pregnancy and lactation
  • Renal, hepatic, or cardiac insufficiency
  • People undergoing pharmacological treatments

The above cases should first be consulted with the doctor. The professional will determine if their use is safe or if they pose any risk. They can also provide guidance on how to use them.

Like this article? You may also like to read: The Incredible Benefits of Frankincense Essential Oil

How to use them safely

The most common way to use essential oils is through diffusers. These dissipate the aromas and allow you to enjoy a pleasant experience. Some people also add them to hot water to inhale the vapors and obtain similar effects.

Their topical use is more delicate. It’s essential to combine a few drops of the oil (5 or 6) with a spoonful of carrier oil (15 ml), which can be coconut, almond, avocado, or olive oil. This is applied through massages on various parts of the body.

However, be careful in case of oily or acne-prone skin, as the application of comedogenic oils can worsen it. Another alternative way is to add a few drops in the bathtub or in preparations for applying compresses.

It’s always a good iea to do a patch test to rule out possible reactions. To do this, apply a small amount of the productto an area of the skin and leave it to act for 6 to 12 hours. If there’s no irritation or discomfort, it can be used without any problem.

Finally, 3 to 5 drops of the chosen oil can be added to shampoo, bath gels, lotions, and other regular care products. Of course, it’s always first necessary to find out if they’re compatible.

What is there to remember about these products?

There’s a wide variety of essential oils on the market with interesting properties. Most are used in aromatherapy to promote relaxation, reduce stress, and soothe certain ailments. However, they can have other positive effects on the nervous, cardiovascular, and circulatory systems.

However, it’s important to use them with caution, as they can have undesirable effects when used in excessive amounts or under certain conditions. In this regard, it’s advisable to read the labels and follow the manufacturer’s recommendations.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

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This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.