Bitter orange (Citrus aurantium) comes from a flowering, fruit-bearing evergreen tree native to tropical Asia, but is now widely cultivated in the Mediterranean region and elsewhere. Bitter orange contains synephrine, an alkaloid with similarities to ephedrine.
Over the centuries, bitter oranges were highly valued for their food and medicinal properties. In ancient China, unripe bitter oranges were used to make zhi shi, an herbal extract used to treat constipation, improve energy (chi) and to calm nerves in cases of insomnia and shock. In the Amazon rainforest, indigenous tribes used bitter orange tea as a laxative and to relieve nausea, stomach pains, indigestion, gas and constipation.
It is claimed that bitter orange is an effective aid to weight loss and a safe alternative to ephedra. However, evidence shows some increase in heart rate and short-term calorie burn, and it may raise blood pressure and exacerbate existing heart problems. Weight loss benefits are unproven and safety questions remain. The U.S. Food and Drug Administration (FDA) banned the sale of ephedrine-containing dietary supplements. Some products previously containing ephedrine have been reformulated to include Citrus aurantium.
Aurantii pericarpium, auraptene, bergamot aromatherapy oil, bergamot orange, bergapten, beta-daucosterol(XI), beta-sitosterol, bigaradier, chisil, Citri aurantii fructus (CAF), Citri grandis pericarpium (CGP), Citrus amara, Citrus aurantium, Citrus aurantium dulcis, Citrus aurantium extract (CAE), Citrus aurantium L., Citrus aurantium L. var. amara, Citrus aurantium sinensis (CAS), Citrus aurantium ssp bergamia, Citrus aurantium var. amara, Citrus aurantium var. dulcis (sweet orange), Citrus bigarradia, citrus essential oils (EOs), citrus extract, Citrus L. Rutaceae, citrus peel extract, Citrus silension (CS), Citrus vulgaris, Citrus xaurantium, corteza de, Cyathifera Y. Tanaka, Daidai, Fructus aurantii, Goutou orange, Goutou sour orange, green orange, hesperidin, Kijitsu, limonene, marmalade, marmin, m-synephrine, naranja amarga, naringin, N-methyltyramine, neohesperidin, neroli oil, nobiretin, non-volatile fraction, octopamine, oil of bergamot, oxedrine, oxypeucedanin, pericarps of Citrus grandis, phenylephrine, pomeranze, Poncirus trifoliate x C. aurantiumsour orange, Rutaceae (family), Seville orange, Shangzhou Zhiqiao, sour orange, sour orange flower, sour orange leaf, sweet orange, synephrine, tangeretin, volatile oil, Xiangcheng, Xiucheng, Zhiqino, Zhi Qiao, Zhi Shi.
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
One low quality study indicates that a combination product including immature bitter orange may improve symptoms of aging. However, more, higher-quality studies are needed.
Preliminary study shows promising results using oil of bitter orange as an antifungal agent. However, further evidence is needed to confirm these results.
Since the ban on ephedra, some weight loss products previously containing ephedrine have been reformulated to include bitter orange. Although bitter orange is popularly used for weight loss, the effects of bitter orange are largely unknown, and more study is needed to make a strong recommendation.
Dementia (behavior challenges)
Bitter orange has been used in aromatherapy, although it does not appear to reduce combative, resistive behaviors in individuals with dementia. Currently, there is no evidence supporting the use of bitter orange for dementia and behavioral challenges.