By Summer Banks on Jun 02, 2017

Bitter orange is an ingredient in many supplements.

It can also be used as a flavoring agent for many foods and beverages. [1]

It can also be found in various medications.

This content takes a closer look at the perks and drawbacks of this stimulant in regards to your health.

What is Bitter Orange?

Bitter orange is a plant that is used primarily for weight-loss products. [2]

It is cultivated in warm areas of tropical Asia. [3]. It can also grow in the Mediterranean, California, and Florida.

In ancient times, certain compounds were extracted from the fruit to be used for Traditional Chinese Medicine (TCM). [4]

TCM is used as an alternative health option. [5]

Other common names for bitter orange include Seville orange, sour orange, zhi shi and citrus aurantium [6] [7]

However, it is most commonly known as synephrine because it contains large amounts of the chemical.

Bottom Line: Bitter orange is a common ingredient in many dietary supplements. It is grown and cultivated in many different areas of the world, but mainly warm and tropical areas. It is known for containing synephrine.

Is Bitter Orange Safe?

A research study published in Phytotherapy Research determined that bitter orange was safe for human consumption and caused no seriously adverse issues. [8]

It was also determined that its primary alkaloid is safe for consumption.

Fortunately, it has been tested on human subjects, which only adds to its reliability. [9]

According to a study published in Food and Chemical: An International Journal Published for the British Industrial Biological Research Association, “Bitter orange extract and p-synephrine appear to be without adverse effects at a dose of up to 98mg daily for 60days based on the parameters measured”. [10]

In this research, there was only changed in the participant’s heart rates, which was caused by an increase in synephrine.

Another study suggests that Nature’s Way Bitter Orange supplements may cause a false positive for amphetamine drug tests. [11]

Bottom Line: Bitter orange is generally safe to consume in moderation, according to various studies. However, certain extracts derived from bitter orange contain a large amount of synephrine, which has been found to cause an increase in an individual’s heart rate. An increase in a heartrate may cause high blood pressure, which can lead to other medical issues.

Is It Good for Weight-Loss?

According to the University of Michigan Health System, bitter orange might be able to promote weight-loss because it contains synephrine. Additionally, it is included in many different supplements because it is chemically similar to ephedrine, which used to be a popular ingredient in anti-obesity products. [12]

In an informational article written by the National Institutes of Health, bitter orange was said to be supported for weight-loss only by small clinical traits. [13]

This same article mentioned it might have an effect on the resting metabolic rate and energy expenditure. [13]

In one study, bitter orange was determined to increase the metabolic resting rate. [14]

The metabolic rate is the amount of energy expended while the heart is at a resting rate. [2]

Increasing this may be able to cause accelerated weight-loss. [15]

This effect was seen primarily in the rat liver. [16]

Bitter orange is also thought to have a thermogenic effect, according to a study published in the International Journal of Medical Sciences. [17]

When mixed with the extracts of green tea and guarana, bitter orange is thought to help increase oxidation rates in resting overweight males after an intense exercise performed on a treadmill. [18]

In a 2004 cited by the National Institutes of Health, supplements containing bitter orange extract have been found to lack efficiency in terms of actual weight-loss. [19]

Additionally, the institute noted that not many studies have been published testing bitter orange for its weight-loss effects, which can make it quite hard to determine its ability to affect weight at all.

Bitter orange is also thought to be ineffective with weight-loss, even though it is said to have certain side effects. [20]

However, the Office of Dietary Supplements claims that bitter orange might increase the number of calories one burns during the day, as well as reducing one’s appetite, which can have a significant effect of an individual’s weight-loss journey. [21]

Bottom Line: Many studies have suggested that bitter orange is not an effective solution for weight-loss. Others say that this ingredient can help weight-loss indirectly by increasing the heart rate, improve oxidation rates, and even help an individual burn more calories while resting.

Bitter Orange and Fungal Infections

Many sources have claimed that bitter orange oil can be an effective treatment for fungal infections.

According to a study published in Mycoses, many different types of oils have been tested for the treatment of such infections, with only a few being effective. [22]

These include tea tree oil preparations, solanum species oil, and bitter orange oil. However, tea tree oil is one that is the most thoroughly tested, having four clinical trials.

Other oils have also been tested for yeast infections, like lemon, Avicenna, and general aroma essential oils.

One study, specifically concerning the oil of bitter orange, found that “OBO (natural product) exerts fungistatic and fungicidal activity against a variety of pathogenic dermatophyte species. It is a promising, cheap, and available topical antifungal therapeutic agent”. [23]

This study was published in The International Journal of Dermatology.

Bottom Line: Although bitter orange is most commonly known for being a part of dietary supplements, it has shown to be quite effective for fungal infections as an oil. However, consult a physician before using any type of herbal treatment for any medical issue.

Health Benefits of Bitter Orange

Bitter orange usually refers to the extract found in supplements.

This synephrine-heavy extract is found in fruit; whose scientific name is Citrus uranium. [24]

However, the fruit is scientifically named Citrus aurantium [25]

Although it is cultivated in other areas, it is naturally grown in Eastern Africa. [24]

According to the Iranian Journal of Pharmaceutical Research, “he findings of the study revealed that aromatherapy using C. aurantium distillated water alleviates labor pain”. [2]

Another study published in Molecules mentioned another health benefit, stating, “The results of the present work reveal that the metabolic action of the C. aurantium extract on liver metabolism and portal perfusion pressure is similar to the actions of other adrenergic agents”. [26]

One research study, published in the World of Gastroenterology, unripe bitter orange is thought to have a beneficial effect on pancreatitis, specifically regarding the enzyme secretions and a decrease in the exudation into the pancreatic substance, abdominal cavity, and retroperitoneal space. [27]

In the text, it specifically states, “…Unripe bitter orange…and Refined mirabilite enhances the small intestinal propulsive function…”. [27]

One study suggested that bitter orange can act as an antibiotic and an antiseptic, if combined with caraway, cedarwood, chamomile, geranium, grapefruit, lemon, marjoram, patchouli, rosemary, sage, sweet orange, ylang-ylang, and English lavender. [28]

In Germany, bitter orange peel, chamomile flower, meadow-sweet flower, willow bark, and linden flower are all combined to make a tea that effectively treats influenza. [29]

Bitter orange tree flowers have been found to contain gallic acid, which can be used in pharmaceuticals. [30] [28]

Bitter orange tree flowers also contain quercetin, which has some anti-bacterial properties. [28]

A study noted that citrus fruit could improve one’s health, like anti-oxidative, anti-inflammatory, anti-cancer, anti-microbial, and anti-allergy effects. [31]

Since bitter orange is a part of the citrus family, by proxy, it has these effects.

Bitter orange is thought to have antioxidant effects as well, according to BioMed Research International. [32]

Bottom Line: Consuming bitter orange has been found to improve general health in many ways. Some of the organs the ingredient effects include the uterus, liver, pancreas, and the intestines. Additionally, bitter orange is thought to improve allergies, influenza, and the function of the immune system. These health improvements are derived from various parts of the bitter orange, including the extract, oil, peel, synephrine extract, and their tree flowers.

What Are the Side Effects?

As with many different products, bitter orange is bound to cause various side effects.

The International Journal of Medical Sciences states that this product does cause side effects, even if they don’t happen to be serious. [33]

The excessive use of bitter orange has been linked to an increased heart rate and high blood pressure. [34] [35]

Some other issues that could arise, but are not likely to occur may include a stroke, heart attack, and fainting. [36]

The Office of Dietary Supplements stated that possible side effects of bitter orange might include chest pain, anxiety, fast heart rate, and high blood pressure. [19]

In some cases, an overconsumption of the stimulant may lead to nausea and vomiting. [37]

The National Institutes of Health reported that some adverse effects could include chest pain and anxiety. [13]

Some possible treatments for high blood pressure may include medication, surgery, and decreasing stress.

If you are experiencing these symptoms, it is important to stay hydrated, increase electrolyte consumption, and eating smaller meals slower. [37] [38]

If you are suffering from any severe symptoms while using bitter orange or supplements that contain it, it is important to consult a physician immediately. [39]

Bottom Line: Bitter orange can cause some side effects if it is used poorly or overconsumed. Some common issues may include high blood pressure, increased heart rate, nausea and vomiting. Its full effect on the human body may be harmful though, so it is important to use caution before and while consuming. [20]

The Bottom Line on Bitter Orange

Bitter orange is a fruit that is often used in the dietary supplement. It is safe for consumption, but too much can lead to a stimulant overdose, which can be detrimental to overall health.

Companies claim it can improve weight-loss, but various studies have suggested that bitter orange is not effective in increasing weight-loss or improving exercise function.

However, it has been proven that it can have many health benefits, including aiding in the function of the immune, reproductive, and gastrointestinal system.

It has also been proven to help treat fungal infections, even though more research is needed to support this claim.

Despite their benefits, there are some significant side effects to using bitter orange, like an increased heart rate, nausea, vomiting, and high blood pressure.

Before starting to use any dietary supplement, it is important so consult your physician to determine its safety, especially if you are under the age of 18, pregnant, breastfeeding, or if you suffer from any kind of health condition.

Additionally, it is important to conduct your research to see if consuming bitter orange is the right think for your weight-loss journey.


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About the Author:

Summer Banks, Director of Content at Dietspotlight, has researched over 5000 weight-loss programs, pills, shakes and diet plans. Previously, she managed 15 supplement brands, worked with doctors specializing in weight loss and completed coursework in nutrition at Stanford University. full bio.