Everything about Lavender

Common Name: Lavender, English Lavender

Scientific Name: Lavandula angustifolia Mill

History and Origin

The Lavandula genus belongs to the Lamiaceae family and includes 39 species, with about 400 registered cultivars. They are worldwide plants that occur over the Mediterranean, Europe, North Africa, and southwest Asia to southeast India.⁽¹⁾ Although lavender originated in the Mediterranean region (Spain, France, Italy, and Andorra), it is cultivated in many other countries, including Poland. The name lavender is derived from “lavo, lavare” (a Latin verb) meaning to wash or to clean. ⁽²⁾

Lavender Plant Structure

Lavender is an evergreen perennial plant, which grows to a height of 40–60 cm and forms compact, regular clumps. The lower part of its stem is woody, and the upper part is green. Lavender has linear or lanceolate leaves with curled edges and a highly branched fibrous root system. Its silver-green leaves are covered with tomentum, which protects them from strong sunshine, wind, and excessive water loss. Lavender's violet flowers grow in spikes, arranged in circles (3–5 flowers per circle) in the top part of the stem. There are also some varieties with white flowers (Alba and Nana Alba) and pink flowers (Rosea). Lavender grows on well-drained, fertile, and lime soils. It grows best in full sun with wind protection. ⁽²⁾

alt text

Fig. 1 The photo of Lavandula angustifolia Fig. 2 The photo of lavender flowers

Lavender Health Benefits

1. Improving Sleep Quality

Lavender has a reputation for being an excellent natural remedy for improving sleep quality and treating insomnia. ⁽³⁾

In 2017, they carried out a study in New Delhi-India, to check the effectiveness of lavender tea out in reducing fatigue, increasing sleep quality, and improving maternal-infant attachment during the postpartum period.

The researchers divided 60 Indian women who had recently given birth and had no history of allergy to herbal teas, foods, or medicines into two groups of 30: the experimental group and the control group.

The control group received only routine postpartum care, but the experimental group was asked to smell the aroma of one cup of lavender tea and drink it 1 hour before bedtime (for 2 weeks).

(Every cup was one lavender black teabag steeped for 10–15 minutes in 300 mL of hot water.)

According to the findings, the mean post fatigue score, the mean post sleep quality level, and the mean post maternal-infant attachment of postnatal mothers in the control group were higher than the experimental group.

It indicates that consuming lavender tea for 14 consecutive days was useful for decreasing fatigue, enhancing sleep quality, and ameliorating maternal infant attachment of postnatal mothers, but regular postpartum care in the control group was not effective in improving maternal infant attachment.

In conclusion, this study supports the popular claim for lavender tea’s beneficial effects on sleep quality, fatigue, and maternal-infant attachment in women who have recently given birth. Furthermore, the lack of reported side effects also supports the claim that lavender tea consumption is a safe, cost-effective, and viable alternative for all clients. ⁽⁴⁾

2. Calming Anxiety and Stress

A study was conducted to investigate the possible anxiolytic property of oral lavender’s flower aqueous extract (LAE) in the chronic mild stress (CMS) rats.

The researchers randomly divided 48 adult male rats into CMS and unstressed groups. The unstressed group was kept under normal conditions. During the stress procedure, the CMS group was housed separately in a different room. Then, they subdivided each group into three groups of 8 rats: the first group received distilled water, the second received LAE (200 mg/kg), and the third received LAE (400 mg/kg).

The treatment lasted for 5 weeks. Every day, the rats were orally fed with distilled water or respective dose of LAE (200 or 400 mg/kg) 1 hour before exposure to CMS procedure. In sum, oral lavender aqueous extracts relieved the anxiety-related behavior in the rats.

This research showed that LAE, regardless of the dose, possessed remarkable anxiolytic property. ⁽⁵⁾

3. Antidepressant Properties

In 2012, in a study, they examined the antidepressant-like effects of an aqueous lavender extract (LAE) in rats using the forced swimming test (FST). (FST is the most commonly used tool for assessing depression.)

When the rats were subjected to an unavoidable stress such as forced swimming, they became immobile. This immobility is considered as a state of despair, in which the animal has learned that escape is impossible. Besides, it has been shown that treatment with known antidepressant drugs will decrease the immobility time in the FST.

LAE was orally administered to the rats three times, i.e., 24, 5, and 1 hour before the FST. LAE (3428 mg/kg body weight) significantly decreased the immobility time in the FST; we can compare it to the effect of the synthetic antidepressant, imipramine (30 mg/kg). The specific constituents responsible for the antidepressant-like effects of LAE are still unclear.

In the present study, linalool, the main constituent of lavender, was completely removed. So, the antidepressant-like effects of LAE can be attributed to its non-volatile constituents.

Lavender has been reported to contain non-volatile phenolic compounds such as hydroxycinnamic acids and flavone glycosides, which can be extracted by hot water and were possibly present in the LAE used in this study. Among the phenolic compounds previously found in lavender, apigenin and rosmarinic acid have been revealed to have an antidepressant-like activity in the FST. ⁽⁶⁾

4. Anti-Microbial

Widespread and indiscriminate use of antimicrobial drugs has led to microorganisms’ resistance against many antibiotics. Therefore, we need to develop natural antimicrobial drugs. We can use medicinal plants, rich sources of antimicrobial agents, as an alternative to antimicrobial drugs.

A study was conducted to investigate the antibacterial effects of different concentrations of lavender aqueous extract on some pathogenic bacteria, including Bacillus subtilis, Streptococcus mutans, Listeria monocytogenes, Yersinia enterocolitica, and Salmonella enteritidis.

The findings showed that lavender aqueous extract has a significant inhibitory effect against all bacteria tested. Its inhibitory effect was higher at higher concentrations studied. Also, the effect of lavender aqueous extracts on Gram-positive bacteria was higher, as compared to Gram-negative bacteria. The extracts had the greatest and the least impact on Bacillus subtilis and Salmonella enteritidis, respectively.

5. Increasing Antioxidant Activity

The antioxidant properties of lavender extracts are mainly attributed to the content of flavonoids and phenolic acid compounds, and to a lesser extent, to certain isoprenoids. However, in comparison with other plants such as green tea, clove, and thyme, lavenders generally possess lower antioxidant activities as measured by their DPPH radical scavenging activity. The reason might be the low content of phenolics; the main phenolic compounds of lavender are rosmarinic acid and caffeic acid, both present in low concentrations.

The extraction technique also affects the overall antioxidant properties of lavender extracts. ⁽⁷⁾

6. Improving Brain Function

In order to examine the effects of lavender aqueous extract (Lavandula angustifolia) on the spatial performance of rats suffering from Alzheimer's disease, a study was carried out. They divided 80 male rats into two groups of control and AD. Then, both groups were introduced to 2 stages of task learning (with an interval of 20 days).

(The basic procedure for the task learning is that the rat is placed in a large circular pool and is required to find an invisible or visible platform that allows it to escape the water by using various cues (Morris water maze test)).

After the first stage of task learning, both groups received different doses of lavender extract or distilled water (50, 100, and 200 mg/kg) for 20 days. After that, they were introduced to the second stage, in the same protocol as that of the first one.

The results showed that in the first stage of the experiment, the time spent to find the hidden platform in the Alzheimer's group was significantly longer than the control group.

In the second stage, control rats that received lavender extract administration at doses of 50, 100, and 200 mg/kg and AD rats that received lavender extract administration at doses of 100 and 200 mg/kg located the platform sooner, as compared with the ones with distilled water treatment.

Based on the results, the lavender extract can effectively reverse spatial learning deficits in AD rats. ⁽⁸⁾

7. Improving Cardiovascular System Function

“Ischemic-reperfusion injury” means a reduction in blood donation to an organ for a short time, and reperfusion may cause damage. In the process of reperfusion, tissue cells produce oxygen free radicals in excess. Oxidative stress is an important factor involved in ischemic-reperfusion injury.

A study was carried out to evaluate the cardioprotective property of lavender flower aqueous extract (LFAE) against myocardial I/R injury in male rats.

According to this study, the pretreatment with LFAE remarkably decreased the myocardial injury degree and the oxidative stress degree, while it increased the myocardial function and the coronary artery flow.

Therefore, we can conclude that LFAE possesses obvious protective effects on myocardial I/R injury, which may be concerned with the improvement of myocardial oxidative stress states. ⁽⁹⁾

8. Anti-cancer

Many studies have confirmed that plants are good natural sources which should be studied as anti-cancer drugs with fewer side effects than chemotherapy and radiotherapy.

A study was conducted to evaluate the anti-cancer properties of lavender aqueous extract on lymphocytes derived from patients with Hodgkin's lymphoma. Findings showed that lavender inhibited cell proliferation in both lymphocytes and cell lines with different effects.

In addition, apoptosis (a form of programmed cell death) was the main mechanism the Hodgkin's lymphoma cell encountered when exposed to the aqueous extract of lavender.

This experiment proposes that lavender aqueous extract can be regarded as a potential anti-cancer agent in future studies.

In vivo studies are vital in order to identify and confirm the exact cytotoxic effect of this extract. Moreover, identifying the effective agent of this extract is necessary for achieving the most successful results. ⁽¹⁰⁾

What Are Lavender Side Effects?

No health hazards or side effects are known in conjunction with the proper administration of designated therapeutic dosages.⁽¹¹⁾

1. When taken by mouth

Lavender is LIKELY SAFE for most adults in amounts commonly found in foods. When consumed orally, lavender may cause constipation, headache, and increased appetite.

2. Pregnancy and breast-feeding

There is not enough information to make sure whether lavender is safe for pregnant or breastfeeding women.

So, stay on the safe side and avoid use.

3. Surgery

Lavender might slow down the central nervous system. If you use it along with anesthesia or other medications given during and after surgery, the central nervous system might become too slow.

So, stop using lavender at least 2 weeks before a scheduled surgery. ⁽¹²⁾

4. Diabetes

In a study, lavender extracts were injected intraperitoneally to experimental animals for 20 days, one dose per day. They observed that lavender flower extracts increased blood glucose levels.

Therefore, in long-term use of lavender, please consider its effect on the glucose level. ⁽¹³⁾

Nutritional Information

Lavender contains essential oil, anthocyanins, phytosterols, sugars, minerals, coumaric acid, glycolic acid, valeric acid, ursolic acid, herniarin, coumarin, and tannins. ⁽¹⁴⁾

Lavender Daily Dosage

To prepare lavender infusion, add 5 to 10 ml (1 to 2 tsp) of lavender herb to 150 ml of hot water, and strain after 10 minutes. You can take the above tea three times a day (each time, one cup). ^{(11, 15)}

In addition, the following doses have been studied in scientific research:

ADULTS (BY MOUTH) - Anxiety: They administered 500 mg of dried, powdered lavender flowers twice a day for 8 weeks.⁽¹²⁾

Bioactive Compounds

The most useful substance isolated from lavender is the essential oil, presented from 2% to 3%. The qualitative and quantitative composition of lavender essential oil is variable and depends on genotype, growing location, climatic conditions, propagation, and morphological features. ⁽²⁾

Best Time to Consume

1-2 hours before or after meals.

Possible Drug Interactions

1. Chloral Hydrate

Chloral hydrate causes sleepiness and drowsiness. It seems that Lavender can increase the effects of chloral hydrate. So, taking lavender along with chloral hydrate might cause too much sleepiness.

2. Sedative medications (Barbiturates)

Lavender might cause sleepiness and drowsiness. Taking lavender along with sedatives (medications that cause sleepiness) might increase their side effects and cause too much sleepiness.

Some sedative medications include amobarbital (Amytal), butabarbital (Butisol), mephobarbital (Mebaral), pentobarbital (Nembutal), phenobarbital (Luminal), secobarbital (Seconal), and so on.

3. Sedative medications (CNS depressants)

Lavender might cause sleepiness and drowsiness. Taking lavender along with sedative medications might cause too much sleepiness.

Some sedative medications include clonazepam (Klonopin), lorazepam (Ativan), phenobarbital (Donnatal), zolpidem (Ambien), and others. ⁽¹²⁾

Use lavender along with CNS depressants and anticonvulsants with caution because it may result in synergistic narcotic and sedative effects. ⁽¹⁶⁾

4. Anticoagulants

Taking anticoagulants along with lavender may increase the risk of bleeding. ⁽¹⁵⁾

Caution is also advised in regard to coumarin, a lavender constituent, theoretically causing bleeding in combination with anticoagulant therapy. ⁽¹⁶⁾

5. Medications used for lowering cholesterol

Taking lavender along with other drugs that lower cholesterol may significantly increase cholesterol-lowering effects.

Some of these drugs are statins, nicotinic acid, fibric acid derivatives.⁽¹⁵⁾

In animal studies, they have observed that 1,8-Cineole lowers cholesterol, which may indicate additive effects with cholesterol-reducing agents. ⁽¹⁶⁾

6. Medications for high blood pressure (Antihypertensive drugs)

Lavender might decrease blood pressure in some people. So, it may interact with medications used for lowering high blood pressure and cause your blood pressure to go too low.

Therefore, do not take too much lavender if you are taking medications for high blood pressure.

Some medications for high blood pressure include captopril (Capoten), enalapril (Vasotec), losartan (Cozaar), valsartan (Diovan), diltiazem (Cardizem), Amlodipine (Norvasc), hydrochlorothiazide (HydroDIURIL), furosemide (Lasix), and many others. ⁽¹⁷⁾

Traditional Use

Lavender is traditionally used orally as an infusion or decoction for relief of a variety of conditions. ⁽¹⁵⁾

Some medieval physicians such as Ibn-e-Sina and Razi have prescribed lavender for treatment of epilepsy and migraine attacks. ⁽³⁾

Uses of English lavender in folk medicine include treating migraine, cramps, and bronchial asthma. ⁽¹⁵⁾

Iran traditional medicine has reported several properties for lavender, including being carminative, diuretic, anti-epileptic, anti-rheumatic, pain reliever especially in nervous headache and migraine. ⁽¹⁸⁾

Some Questions about Lavender

Does lavender tea help you sleep?

Lavender tea is well-known for its calming properties; it can relax the mind and body. ⁽¹⁹⁾

Infusions and tinctures of lavender flowers have sedative and analgesic properties. ⁽²⁰⁾

Can you be allergic to lavender?

Within 5 to 10 minutes of coming into contact with lavender, some people may experience a skin reaction. It is the most common type of reaction. ⁽²¹⁾

Moreover, some people may have an allergic reaction to lavender tea. So, stay on the safe side and take a small amount the first time. If there is no problem, continue its use. ⁽²²⁾

What parts of lavender are edible?

Lavender (L. angustifolia) flowers, buds, and leaves are edible. ⁽²³⁾

What kind of lavender is used for tea?

English lavender (L. angustifolia) is the most common species of lavender used. However, other species such as Lavandula burnamii, L. dentate, L. dhofarensis, L. latifolia, and L. stoechas are used too. ⁽²⁴⁾

Is lavender safe for males?

According to the laboratory evidence, lavender has estrogenic (estrogen-like) properties and anti-androgenic (testosterone inhibiting-like) activities, meaning it competes or hinders the hormones that control male characteristics, which could affect puberty and growth. ⁽²⁵⁾

Also, a new study has new evidence that lends weight to a suspected link between abnormal breast growth in young boys - called prepubertal gynecomastia - and regular exposure to lavender oil. The findings show that lavender oil's key chemicals act as endocrine-disrupting ones. (An endocrine-disrupting chemical is a chemical in the environment that interferes with hormones and their actions in the body.)

Prepubertal gynecomastia is relatively rare, but a growing amount of cases have been reported to coincide with topical exposure to lavender oil, and the condition went away after the boys stopped using the oil-containing products.

Does lavender cause hormone imbalance and increase breast size?

A 7-year study was conducted by clinicians at Nicklaus Children's hospital in Miami, Florida. They examined 24 patients who presented with either prepubertal gynecomastia or premature thelarche. Among the cases, they found that five girls with transient thelarche had been exposed to lavender-containing products. In each case, after the girl discontinued lavender exposure, the issue was resolved.

Besides, 11 of the 19 boys treated for prepubertal gynecomastia were also exposed to lavender-containing products. ⁽²⁶⁾