Bitter orange weight-loss supplements: Do they work?

There's no definitive evidence that bitter orange (Citrus aurantium) is effective for weight loss. After ephedra was taken off the market due to its health concerns, many consumers — and weight-loss supplement manufacturers — began looking for alternatives. One such alternative is bitter orange, which has become a common ingredient in many weight-loss supplements marketed as "ephedra-free." Unfortunately, many of the health problems associated with ephedra seem likely to also occur with bitter orange.

Bitter orange contains synephrine and octopamine — chemicals that are similar to ephedrine in ephedra. These chemicals may cause high blood pressure (hypertension) and heart rhythm disturbances (arrhythmias), which can lead to heart attack, stroke and even death — as may occur with ephedra. Also, bitter orange juice — like ephedra — can inhibit metabolism of many drugs, increasing the amount of the drug in your body and the risk of adverse effects.

Because dietary supplements are subject to far less rigorous regulatory oversight than are pharmaceutical drugs, they may contain higher amounts of bitter orange than is listed on the label. This further increases the risk of adverse effects. People with existing heart disease, high blood pressure or other cardiovascular problems should avoid bitter orange. People who take medications, such as monoamine oxidase inhibitors (MAOIs), that speed up the heart rate also should avoid bitter orange.  Eating less and exercising more still appears to be the safest and most effective approach to losing weight.