History and Origin
Bitter orange is native to Eastern Africa and the tropical regions of Asia. Today this tree grows across the Mediterranean region and some parts of the United States; orchards of bitter orange are found along the Mediterranean coast, particularly in Spain. It is thought to be introduced into Europe around the year 1200 by Arab tradesmen. During the 17th century, the Italians, the Spaniards, and the French used this plant extensively. The application of this plant dates back to ancient times. Ancient Greeks used it for disinfection in Aromatherapy (smell therapy) and herbal therapy.
Bitter Orange Plant Structure
Bitter orange, also called Seville orange, marmalade orange, bigarade orange, and sour orange, refers to a citrus tree (Citrus × aurantium) and its fruit. It belongs to the order Geraniales and the Rutaceae family.
A tree or rarely a shrub that its young shoots are glabrous and greenish-white:
The leaflets are 7.5 – 15 cm, long, elliptic or ovate, obtuse, acute or acuminate. The petioles are naked or winged; the wings are often obovate and nearly as large as the blade.
The flowers are bisexual and pure white, with 20-30 stamens.
The fruit is globose, generally oblate, not mammillate, usually orange-colored, rind loose, or adherent; the pulp is sweet, yellow, and rarely red. (1)
The photo of Citrus × aurantium L. The photo of bitter orange blossom
Bitter Orange Health Benefits
1. Regulating Irregular Heartbeat
In a research, they studied the effect of various concentrations of Citrus aurantium essence on the electrophysiological properties of isolated heart with the help of the atrioventricular node model as well as the protective role of Citrus aurantium essence on arrhythmia (irregular heartbeat) in rabbits. (After passing through the corridors and reaching the ventricles, the electrical current in the heart must pass through a structure called an atrioventricular node).
They examined three groups of rabbits (6 rabbits in each group and 18 rabbits in total).
The results indicated depressant effects of various concentrations of the extract on increasing electrophysiological parameters (AV Conduction Time, Effective, and Functional Refractory Periods (ERP & FRP)); AV Conduction Time significantly increased from 32.6±3.6 millisecond (ms) to 40±6.08 ms and FRP from 147.5±5.1 ms to 166.6±3.6 ms.
As a result, the research has suggested that Citrus aurantium might help to regulate heartbeat.
2. Calming Anxiety and Stress
In a clinical study, the bitter orange blossom effect on stress was investigated in nulliparous women. The results of this experiment showed that smell therapy with bitter orange blossom reduces the anxiety of childbirth. The oily extracts improve the mood and reduce the level of anxiety during childbirth by stimulating the routes in the limbic system of the brain. These extracts are absorbed through respiration; they can affect enzymes, ion channels, and receptors and can lead to brain stimulation, anxiety relief, and cerebral blood flow increase. Also, they have anti-depressant effects. These oily extracts can pass from the blood-brain barrier through breathing and interact with receptors in the central nervous system.
Akhlaghi et al compared the effects of Citrus aurantium to the effects of Diazepam in reducing anxiety before surgery. In this study, they selected 60 patients referring for surgery, aged 14 to 48 years, and randomly divided them into two groups of thirty people. Two hours before surgery, they gave 100 cc Citrus aurantium to group 1, and oral solution of a 5 mg Diazepam pill in 100 cc water to group 2; and measured their anxiety and vital signs before medication and two hours after medication. The results showed that the amount of anxiety reduced in both groups; they both experienced lower levels of stress after taking the drug. As a result, Citrus aurantium can be an effective premedication for reducing the patients’ anxiety before surgery.
3. Regulating Blood Pressure
In a research published in Evidence-Based Complementary and Alternative Medicine journal, they investigated the effects of inhalation of bitter orange blossom essential oil on high blood pressure and salivary cortisol levels in 83 people with high blood pressure for 24 hours.
Based on this study, inhalation of neroli essential oil significantly reduces systolic and diastolic blood pressure and the density of salivary cortisol (cortisol hormone secrets in response to stress). This study showed that smelling bitter orange blossom essential oil has positive effects on blood pressure and decreasing stress. (3)
4. Anti-Microbial
According to researches, the Citrus aurantium L. flowers essential oil (neroli oil) has anti-microbial and anti-oxidant properties. A research published in Pakistan Journal of Biological Sciences suggests that neroli oil has anti-microbial properties against all bacteria tested (especially pseudomonas aeruginosa bacteria, except for Staphylococcus aureus), two types of yeast, and three types of fungus tested. The results showed the strong antifungal activity of neroli oil in comparison with the standard antibiotic (Nystatin). (4)
What Are Bitter Orange Side Effects?
No health hazards or side effects have been known in conjunction with the proper administration of designated therapeutic dosages but to be on the safe side, note the following: (5)
1. Pregnancy and Breast-Feeding
Bitter orange is Likely SAFE during pregnancy when used in reasonable amounts found in food. However, it is POSSIBLY UNSAFE and NOT RECOMMENDED when taken orally in medicinal amounts. The effects of bitter orange on breast-feeding infants are not known.
Thus, stay on the safe side and do NOT use bitter orange during pregnancy or breast-feeding.
2. Diabetes
Some evidence shows that bitter orange may interfere with blood sugar control in patients with type 2 diabetes.
Diabetic patients should use it with caution and monitor their blood sugar levels closely.
3. High Blood Pressure
Some studies suggest that bitter orange can increase blood pressure in healthy people, especially when taken with caffeine. However, other studies have found no such blood pressure elevation. Furthermore, to date, there have not been any studies looking at the effect of taking bitter orange orally in people with high blood pressure.
If you have high blood pressure, avoid using bitter orange, especially in combination with stimulants such as caffeine.
4. Glaucoma
Bitter orange might worsen glaucoma. Avoid using it if you have this condition.
5. Heart Disease
Consumption of bitter orange, especially in combination with caffeine or other stimulants, might increase the risk of serious side effects in people with long QT syndrome, a particular heart disorder.
6. Irregular Heartbeat (Heart Arrhythmia)
Some studies suggest that bitter orange, especially when taken with caffeine, may increase heart rate in healthy people. Other studies have found no evidence of such an effect on heart rate.
There have been no studies on the effects of bitter orange on people, who have an irregular heartbeat.
Avoid using bitter orange, if you have an irregular heartbeat, especially in combination with stimulants such as caffeine.
7. Surgery
Bitter orange acts like a stimulant. Thus, it may interfere with surgery by increasing heart rate and blood pressure. Stop the consumption of bitter orange at least 2 weeks prior to a scheduled surgery. (6)
Nutritional Information
Food value per 100 g of the edible portion of bitter orange is moisture, protein, fat, carbohydrates, fiber, ash, calcium, iron, phosphorus, vitamin A, thiamine, riboflavin, niacin, ascorbic acid. (7)
Bitter Orange Daily Dosage
Follow the manufacturer's dosage guidelines because synephrine content may vary in supplement formulations. (2)
Bioactive Compounds
The flower of Citrus aurantium contains some compounds like neohesperidin, synephrine, adenosine, asparagine, tyrosine, valine, isoleucine, alanine, beta-sitosterol, and beta-daucosterol.
Besides, the dried flowers contain Steroid- Desmosterol, Ergosterol, β-Sitosterol, Stigmasterol, and Saponins.
Alkaloid- caffeine was reported in dried flower extract.
Flower essential oil contains Monoterpene- b-limonene, Linalool, Linalool acetate.
Best Time to Consume
2 hours before or after meals.
Possible Drug Interactions
1. Medications for Depression (MAOIs)
Bitter orange contains chemicals that stimulate the body. Some anti-depression drugs, including phenelzine (Nardil) and tranylcypromine (Parnate), taken with bitter orange may increase these chemicals, which might cause serious side effects including fast heartbeat, high blood pressure, nervousness and even result in seizures.
2. Midazolam (Versed)
The body breaks down midazolam (Versed) very quickly in order to get rid of it. Bitter orange can slow down liver functionality to break down midazolam (Versed). Thus, taking bitter orange along with midazolam (Versed) might increase the effects and side effects of midazolam (Versed).
3. Caffeine (Excedrin, Anacin, Vivarin, and others)
Bitter orange is a stimulant like Caffeine. Their combination may result in higher blood pressure as well as increased heart rate, which can lead to some serious adverse side effects such as heart attack and stroke.
4. Dextromethorphan (Robitussin DM, and others)
The body breaks down dextromethorphan (Robitussin DM, others) very quickly in order to get rid of it. Bitter orange can slow down liver functionality to break down dextromethorphan (Robitussin DM, others). Thus, taking bitter orange along with dextromethorphan (Robitussin DM, others) might increase the effects and side effects of dextromethorphan (Robitussin DM, others).
5. Felodipine (Plendil)
Felodipine (Plendil) is used to lower blood pressure. The body breaks down felodipine (Plendil) very quickly in order to get rid of it. Bitter orange can slow down liver functionality to break down felodipine (Plendil). Thus, taking bitter orange along with felodipine (Plendil) might increase the effects and side effects of felodipine (Plendil).
6. Indinavir (Crixivan)
Indinavir (Crixivan) is used to treat HIV/AIDS. The body breaks down indinavir (Crixivan) very quickly in order to get rid of it. Bitter orange can slow down liver functionality to break down indinavir (Crixivan). Thus, taking bitter orange along with indinavir (Crixivan) might increase the effects and side effects of indinavir (Crixivan).
7. Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates)
Taking bitter orange along with some medications that are broken down by the liver can increase the effects and side effects of some medications. Before taking bitter orange, talk to your healthcare provider if you are taking any medications that are changed by the liver.
Some medications changed by the liver include lovastatin (Mevacor), ketoconazole (Nizoral), itraconazole (Sporanox), fexofenadine (Allegra) and triazolam (Halcion).
8. Stimulant drugs
Taking bitter orange along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure.
It is highly recommended NOT to consume stimulant drugs such as diethylpropion (Tenuate), epinephrine, phentermine (Ionamin), and pseudoephedrine (Sudafed) along with bitter orange. (9)
Traditional Use
In the Canary Islands, they used an infusion of dried flowers of C.aurantium var amara orally for influenza, insomnia, and as a tranquilizer.
Extract of dried flowers of C.aurantium var amara was taken orally as a cardiovascular analeptic in Tunisia.
Infusion of dried flowers was used orally for cold and antispasmodic in Brazil.
Infusion of flower and leaf was used orally as a sedative and digestive in Italy.
Infusion of dried flowers was used orally as a digestive in Spain.
Some Questions about Bitter Orange
Is bitter orange good for weight loss?
Clinical trials have examined the effects of bitter orange products alone or in combination with other ingredients on body weight and body composition.
The anti-obesity effect of bitter orange contains synephrine, which is a stimulant. Furthermore, bitter orange is believed to increase your basal metabolic rate, which results in weight loss and calorie burn while our body is at rest by stimulating fat breakdown and suppressing appetite.
Does bitter orange suppress appetite?
Bitter orange contains synephrine, a compound that may be effective in reducing appetite.
Is bitter orange dangerous?
Decoctions of bitter orange substantially increase blood levels of cyclosporine, causing toxicity. Bitter orange contains synephrine and octopamine; these chemicals may cause high blood pressure (hypertension) and heart rhythm disturbances (arrhythmias), which can lead to heart attack, stroke, and even death.
For more information on possible side effects of “Bitter Orange”, see the “What Are Bitter Orange Side Effects?” section.
Is bitter orange a stimulant?
Some sources recognize bitter orange as a stimulant. On the other hand, many sources suggest that it is not a stimulant if consumed in appropriate doses.
However, the National Collegiate Athletic Association (NCAA) has stated synephrine (bitter orange) in their list of banned drugs, which acts as a stimulant.
References
1. https://www.researchgate.net/
2. https://www.drugs.com/
3. https://draxe.com/
4. https://scialert.net/abstract/
5. (2000). PDR for herbal medicines. 2nd ed. Montvale, NJ: Medical Economics Company.
6. https://www.webmd.com/
7. https://hort.purdue.edu/
