Bitter Orange: The Metabolism Boosting Fruit

Did you know a specific fruit could help you drop some unwanted weight? There’s a type of orange that is growing in popularity for just that. It’s called a bitter orange and it contains an organic compound that stimulates fat oxidation. Not only that but bitter orange has been used as a treatment for anxiety, epilepsy, gastric disorders, and more. 

What’s Bitter Orange?

Citrus aurantium, known as bitter orange, is a citrus fruit native to East Africa, the Arabian Peninsula, Southeast Asia, and Syria. Although you can now find it in the Mediterranean region, Florida, and California. The other common names for bitter orange are sour orange, Seville orange, marmalade orange, and bigarade orange [1]. Originating in Traditional Chinese Medicine, the bitter orange provides a range of health and exercise benefits. That’s because of the many nutrients and compounds it contains. Those include:

• Synephrine
• Limonene
• Octopamine
• Vitamin C
• Flavonoids

These natural compounds are extracted from the fruit and peel of bitter oranges for higher potency. The primary proto-alkaloid, p-synephrine, is used in sports performance and weight loss supplements. [2].

How Does Bitter Orange Help You Lose Weight?

Bitter orange extract contains p-synephrine, which increases thermogenesis and fat oxidation, especially when combined with exercise. Several studies have shown that p-synephrine acts as a beta-3-adrenoceptor, meaning it binds to the beta-3 receptors in fat cells. They then activate the beta-3s which promote the breakdown of fat cells, relaxation, and increased bladder capacity [3]. 

One study recorded the effects of taking a bitter orange extract for 12 weeks. Some took the bitter orange extract alone, while others took that in combination with other ingredients. The results showed that both groups saw significant increases in resting metabolic rate [4]. Plus, when taking bitter orange/p-synephrine for up to 12 weeks can result in modest weight loss. 

Other studies found that bitter orange is beneficial to people trying to up their fat utilization during exercise rather than carbohydrate stores [5]. 

What’s the Best Dosage?

There’s a lot of discussion on whether p-synephrine makes bitter orange a stimulant. However, data shows that bitter orange didn’t increase blood pressure or cause significant changes in heart rate. Although that doesn’t mean it’s not a possibility. Research has determined that doses from 49mg to 98mg are optimal to prevent adverse effects [6]. And many bitter orange supplements on the market reflect those numbers. 

References:

1. U.S. Department of Health and Human Services. (n.d.). Bitter orange. National Center for Complementary and Integrative Health. Retrieved April 2, 2023, from https://www.nccih.nih.gov/health/bitter-orange  
2. The safety of bitter orange (citrus aurantium) and p-synephrine - american botanical council. (n.d.). Retrieved April 2, 2023, from https://www.herbalgram.org/resources/herbalgram/issues/89/table-of-contents/feat_bitterorange/
3. Beta-blockers: Types, uses and side effects. Cleveland Clinic. (n.d.). Retrieved April 2, 2023, from https://my.clevelandclinic.org/health/treatments/22318-beta-blockers#:~:text=Beta%2D3%20(B3)&text=Cause%20fat%20cells%20to%20break,for%20B3%20receptor%2Dtargeted%20medications.  
4. Stohs, S. J., Preuss, H. G., & Shara, M. (2012). A review of the human clinical studies involving citrus aurantium (bitter orange) extract and its primary protoalkaloid p-synephrine. International journal of medical sciences. Retrieved April 2, 2023, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3444973/  
5. Ruiz-Moreno, C., Del Coso, J., Giráldez-Costas, V., González-García, J., & Gutiérrez-Hellín, J. (2021, January 15). Effects of p-synephrine during exercise: A brief narrative review. Nutrients. Retrieved April 2, 2023, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7830131/  
6. SJ;, K. G. R. M. H. P. H. G. S. (n.d.). A 60day double-blind, placebo-controlled safety study involving citrus aurantium (bitter orange) extract. Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association. Retrieved April 2, 2023, from https://pubmed.ncbi.nlm.nih.gov/23354394/