As the famous April showers begin, I’m reminded of the distinct odor in the air before and after it rains. But rainwater is actually colorless and odorless. So what causes this smell?
The aroma occurs when rain “activates” nutrients in the plants and soil. In particular, rainwater releases oils that plants produce during dry, dormant periods. These oils are essential for inhibiting a plant’s growth and reducing its need to compete for limited moisture in the soil. But, when it rains, the plant no longer needs to inhibit its growth, so these intoxicating scents are released.
But these oils aren’t just powerful compounds for the plant—they also can also have effects on other living organisms, from insects, to animals, to humans. In fact, these aromatic oils are the basis of one of the biggest recent natural health trends: essential oil aromatherapy. But unlike some health trends, the use of essential oil aromatherapy has quite a bit of solid science to support it. Of course, there are a few guidelines you should follow in order to find a quality product. And I’ll tell you more about that in just a moment.
But first, let’s take a closer look at how aromatherapy works. And, of course, it all starts with our sense of smell.
You see, our olfactory nerves (which are a big contributor to our sense of smell) are connected directly into the brain. That means our brains are connected to smells like no other kind of sensory input. Which is likely why smells can conjure up such strong emotions and memories.
But a plant’s essential oils can do even more for our health. Studies show that many essential oils are naturally antibacterial, antimicrobial, and antifungal. Plus, there’s quite a bit of research showing that essential oil therapy can help lower stress, alleviate pain, reduce inflammation, and improve sleep.
A roadmap for how essential oils work in the body and brain
Pain, inflammation, and stress. Science shows that aromatherapy can alleviate pain symptoms and associated emotional distress by targeting hormonal and neural pathways that involve the “feel-good” neurochemicals—endorphins, dopamine, oxytocin, and serotonin.
Essential oils also influence the release of neurochemicals associated with inflammation and stress—specifically adrenalin and cortisol.
A variety of essential oils have these characteristics, including: chamomile, clove, eucalyptus, frankincense, geranium, ginger, grapefruit, jasmine, juniper, lavender, lemongrass, marjoram, pine, rose, rosemary, sage, spruce, thyme, vanilla, wintergreen, and ylang ylang.
Sleep and relaxation. Aromatherapy can provide an ideal, pill-free sleep solution. Research shows that lavender and chamomile essential oils help you to relax and ease you into sleep. They also help reduce cortisol levels to promote inner calm and reduce the effects of daily stress.
Orange and peppermint essential oils (and their botanical constituents called terpenes) can also promote relaxation and sleep.
How to use essential plant oils
While rain releases some plant oils, most commercially available essential oils are typically obtained by distillation of plant material.
Plant oils can be extracted from bark (cinnamon), blossoms (orange or neroli), bulbs (garlic, onion), dried flower buds (cloves), flowers (lavender, rose), fruits (lemon, orange), grasses (lemongrass), gums and resins (frankincense or boswellia), leaves (eucalyptus, peppermint), roots (calamus, ginger), or wood (camphor, sandalwood).
The amount of raw plant material to obtain usable amounts of oil varies, which is why essential oils fluctuate quite a bit in price. For example, when I was researching my book Fundamentals of Complementary & Integrative Medicine (now in its 6th edition), I discovered that it requires a whopping 220 pounds of fresh rose petals to extract just two ounces of rose oil.
Essential oils may be inhaled directly or applied to the skin. When they’re used topically, the oils are usually diluted in a carrier oil, like coconut oil. Otherwise, the oils are too potent and may cause skin irritation when used alone.
Essential oil mixtures can also be used as massage oils, mixed into topical ointments, applied in compresses, or rolled right onto the pulse points like perfume. When the oils are applied topically, some aroma is naturally inhaled, but the oil works mainly by being absorbed into the skin and then transported into the bloodstream.
In fact, research shows that lavender massage oil, for instance, penetrates the skin after 10 minutes and reaches maximum blood concentrations in just 20 minutes.
Finding the best essential oils
When shopping for essential oils, it’s important to note that there’s no standard definition for the purity or therapeutic benefits. But to help ensure you’re getting a high-quality oil, do some research—on the oil itself, and on the brand. Remember to be wary of big online retailers like Amazon (as I recently warned)! Instead, you’ll want to look for brands that stand behind each and every one of their products, perhaps with a 100% satisfaction guarantee.
To help ensure purity, choose organic or wild-crafted oils, which usually don’t contain pesticides. And check to see that the formula is 100 percent pure essential oil. Some manufacturers dilute pricey oils, like rose oil, with vegetable oils to create more volume.
Essential oils should also be sold in dark glass bottles. This helps prevent light from entering, which can cause the oil to spoil.
So always be sure to avoid plastic containers, which can degrade and contaminate the oil. Lastly, make sure the label contains a country of origin and an expiration date.