Educational information, not medical advice — ask your doctor or midwife.
Naranja agria is the sour orange, Citrus x aurantium. It is a sharp, bitter citrus fruit. In Latin America it is mostly a kitchen ingredient.
Cooks use the juice in marinades such as Cuban mojo and Yucatán cochinita pibil. Home remedies use the peel, the leaves and the flowers. Flower water, called agua de azahar, is a common calming drink.
Supplement makers sell something quite different. It is a strong peel extract, rich in p-synephrine. That is a stimulant-like compound.
Here is the short verdict. Food amounts suit most people. The concentrated extract has weak proof of benefit and real heart risks.
Long use in a tradition is not proof that something works. It is not proof that it is safe either. Both points matter for this fruit, because the food and the supplement behave very differently.
The clearest effect in people is a drug interaction, not a health benefit.
Sour orange juice contains furanocoumarins. In human studies these block CYP3A4, a gut enzyme that breaks down many drugs. Blocking it can push drug levels in the blood higher, much like grapefruit juice does.
p-Synephrine is the compound in peel extracts. In lab and animal studies it acts on adrenaline-type receptors. That may raise heart rate, blood pressure and calorie burn a little.
Small human studies show modest shifts in heart rate and blood pressure. These show up most when synephrine is paired with caffeine. Whether it burns enough fat to change your weight is not established.
Bitter flavonoids are the traditional reason for peel tea after a heavy meal. The idea is that a bitter taste prompts saliva and digestive juices. That idea has not been tested well for this fruit.
Orange blossom tea is used for nerves. Animal work on the flower and its oil hints at a calming effect. Good human trials are lacking.
You will meet this fruit in very different forms. The food forms and the supplement forms are not the same risk.
- Fresh fruit and fresh-squeezed juice, used in marinades and dressings. - Bottled sour orange juice, sold in Latin American groceries. - Dried peel, brewed as a tea.
- Marmalade and candied peel. - Agua de azahar, orange blossom water, and flower tea. - Essential oils: neroli from the flowers, petitgrain from the leaves, bitter orange oil from the peel.
- Capsules and tablets of peel extract, standardised to p-synephrine. - Pre-workout, fat-burner and "thermogenic" blends, usually with caffeine.
The blends are the main source of reported harm. Read the full ingredient list, not just the front of the tub.
Spanish and Portuguese settlers brought the sour orange to the Americas in the 1500s. The tree had travelled from Asia through the Arab world and the Mediterranean. It took hold quickly in the Caribbean, Mexico and Central America.
In home tradition the fruit had set jobs: - Peel tea after heavy food, for gas and a full stomach.
- Agua de azahar for nerves, fright and restless children. - Juice with honey for coughs and colds. - Juice as a meat marinade and a kitchen rinse.
The fruit has a long record outside Latin America too. Chinese medicine used the unripe fruit as zhi shi. European pharmacies sold the dried peel as a bitter tonic.
The weight-loss use is recent. It grew in the early 2000s, after ephedra was pulled from supplements. Makers needed a legal stimulant, and synephrine filled the gap.
Call emergency services now if you get chest pain, a pounding or irregular heartbeat that will not settle, fainting, sudden severe headache, one-sided weakness, or slurred speech.
Stop the product and see your doctor if you notice a steady rise in blood pressure, ongoing palpitations, bad anxiety, or sleep that will not return.
Tell your doctor or pharmacist before you start if you take any daily medicine. Bring the label, since blends often hide caffeine.
In the United States the fruit and juice are ordinary foods, while peel extracts are sold as dietary supplements and are not tested for effect before sale. Health Canada limits synephrine in licensed products, and the FDA has warned about weight-loss blends that combine synephrine with caffeine. Competing athletes should note that synephrine sits on the World Anti-Doping Agency monitoring list and octopamine is banned.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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