Untitled Document
Bitter orange (Citrus aurantium) is the type of orange often used to make orange marmalade. Also known as Seville orange or bigarade orange, bitter orange lives up to its name as one of the most tart and pungent citrus fruits. Bitter orange is popular as an essential oil and athletic supplement, but certain side effects may have you wondering whether it's safe for consumption on its own. Here's some background on this unique food item.
Bitter Orange Nutrition Facts
The nutrition information on bitter orange is scarce and not currently available from the USDA. The following is provided by the most recent data from Purdue University's Horticulture Department for 100 grams of raw bitter orange.
- Calories: 37–66
- Carbohydrates: 9.7–15.2g
- Fiber: 0.4g
- Protein: 0.6–1g
Carbs
In 100 grams of bitter orange (which is about the size of a small orange), there are about 10–15 grams of carbohydrate. This includes just under 1/2 gram of fiber. Information on sugar content is not readily available for bitter orange, but it's safe to assume that it contains some natural fructose (as do most fruits).
Protein
There is under 1 gram of protein in 100 grams of bitter orange.
Vitamins and Minerals
Bitter orange is high in vitamin C, with 45–90 milligrams per serving. Bitter orange also provides some calcium and vitamin A.
Health Benefits
Bitter orange oils, extracts, and supplements are used by alternative practitioners for a variety of health purposes. Here are the benefits supported by research.
Treats Fungal Infections
Bitter orange is considered to be effective for several skin issues, including ringworm and athlete's foot. Older studies have demonstrated bitter orange oil as a fungicide when applied topically, fighting against conditions that are otherwise resistant to treatment. As an added bonus, there are very few (if any) noted negative side effects to the external application of bitter orange, suggesting that it can be used with little risk.
Aids Wound Healing
In alternative medicine, bitter orange is also sometimes applied topically in an effort to speed the healing of bedsores. Although this effect isn't necessarily common practice, oral intake of bitter orange provides a fair amount of vitamin C. Vitamin C is a precursor to collagen, making it essential for skin integrity and repairs. With 45–90 milligrams, a serving of fresh bitter orange offers 50% to 100% of the daily requirements for vitamin C.
May Help Support Weight Loss
Bitter orange has shown promising effects for weight loss when combined with caffeine in both human and rat studies. The active ingredient, p-synephrine is a known stimulant. In humans, bitter orange has demonstrated increases in metabolic rate and energy expenditure over a 6–12 week period. In rats, bitter orange extract produced a 30% decline in visceral fat during a 13-week trial period.
May Support Diabetes Management
There's some limited evidence for the use of bitter orange in reducing blood glucose. A 2017 study from Nigeria showed that citrus essential oil effectively inhibits the enzymes α-amylase and α-glucosidase, both of which are linked to diabetes and hypertension. This effect is not limited to just bitter orange, as lemon and grapefruit peels show similar results.
May Help Prevent Some Cancers
Bitter orange also contains several flavonoid compounds with antioxidant effects, including hesperidin and limonene. By inducing apoptosis, hesperidin inhibits the viability of ovarian cancer cells. Limonene demonstrates anticancer effects on the liver by modulating the genes that contribute to liver cancer development. Although not a substitute for evidence-based cancer therapy, further studies on bitter orange may produce innovative supplementary treatment options.
Allergies
Allergies to citrus fruits like bitter orange can involve a cross-reactivity with pollen or other plants. Symptoms of orange allergies may include vomiting, abdominal pain, or diarrhea. If you have a known allergy to citrus foods, it's probably best to avoid bitter orange products altogether. See an allergist for testing if you suspect that you have a food allergy.
Adverse Effects
Bitter orange juice is considered as safe to drink as any other citrus fruit juice (as long as it is not consumed in excess). Far less is known about the long-term safety of bitter orange extracts and supplements.
Because the synephrine in bitter orange acts as a mild stimulant, combining it with other stimulants, like caffeine, may trigger dangerous side effects. These can include:
- • Jitters
- • Headache
- • Increased heart rate
- • Increased blood pressure
- • Sun sensitivity (including increased sunburn risk)
The overuse of these supplements, whether for weight loss or athletic performance, may trigger abnormal heart rhythms (arrhythmias), lightheadedness, fainting, and other potentially severe symptoms. Bitter orange is banned by the National Collegiate Athletic Association (NCAA).
Bitter orange may interact with monoamine oxidase inhibitors (MAOIs), a class of antidepressants that includes medications like Emsam (selegiline), Marplan (isocarboxazid), Nardil (phenelzine), and Parnate (tranylcypromine). Bitter orange may increase the concentration of MAOIs in the blood and, with it, the risk of side effects. Bitter orange also appears to break down benzodiazepine sedatives like Versed (midazolam) and Halcion (triazolam), making them far less effective.
While some experts have suggested that bitter orange may have as many drug interactions as grapefruit, its effects don't appear to be as strong. Check with your doctor to be sure. Pregnant and breastfeeding women should avoid bitter orange products because their effects are unknown and have not been proven safe.
Varieties
There are several varieties of bitter orange, including the "normal" group, "aberrant" group, and the "bittersweet" group. The normal group describes large and seedy fruits that are high in pectin. Specifically, the Oklawaha originated in the U.S. and is commonly used to make marmalade.
Within the aberrant group is the Daidai, or Taitai, a popular variety in China and Japan. This acidic fruit has a thick peel and lots of seeds. Darker and sweeter varieties are found in the bittersweet group, such as the Paraguay and Karna.
For medicinal purposes, bitter orange is typically sold as a tablet, gelcap, or extract. Herbalists will often sell powdered bitter orange peel to mix in topical creams and ointments. Zhi shi is also available in powdered form.
There are no standardized prescribing recommendations for bitter orange. As a rule of thumb, if you decide to use a bitter orange supplement, do not exceed the recommended dose on the product label.
When It's Best
Bitter oranges can be bought fresh in grocery stores (usually as Seville oranges). If you cannot find them locally, there are online suppliers who offer to ship. Seville orange juice is also sometimes sold, either in fresh or pasteurized forms.
Bitter orange extracts and supplements can be found a many health food and vitamin supplement stores, as well as online. Bitter orange essential oils can be purchased at many of the same outlets.
Storage and Food Safety
Bitter orange supplements should be stored according to the instructions listed on the particular product. Be mindful of expiration dates. If you purchase fresh bitter oranges, treat them as you would other fresh produce. Wash fruit under running water before cutting into it. Once cut, store bitter orange slices in the refrigerator in an airtight container and use within a few days.
How to Prepare
Bitter orange has had many versatile uses in global cuisine. Although it's not typically consumed fresh like other citrus fruits because it is very sour, in Mexico, bitter orange is sliced in half and served with salt and a slice of chili pepper. Bitter orange juice is used to flavor fish and meat in Spain, with vinegar-like uses in the Yucatan.
Egyptians even ferment bitter orange to make wine. In England, Scotland, and South Africa, marmalade is made from bitter orange. Bitter orange oil is used all over the world to flavor liqueur, chewing gum, ice cream, gelatin, and candy. Even if you don't prepare it yourself, there's a chance you'll come across bitter orange in products you already purchase.