Some research has even reported that caffeine and ephedrine individually had no effects on weight loss, while the combination of the two did produce weight loss Over 12 weeks, ingesting a combination of ephedra and caffeine 3 times per day led to a reduction of 7.
Another 6-month study in overweight and obese people compared a supplement containing ephedrine and caffeine to a placebo during a weight loss program The group taking ephedrine lost 9. The ephedrine group also decreased body weight and LDL bad cholesterol more than the placebo group.
Overall, the available evidence indicates that ephedrine-containing products — particularly when paired with caffeine — may increase weight and fat loss. Ephedrine plus caffeine may increase metabolic rate and fat loss more than either ingredient alone. Studies show the combination of ephedrine and caffeine produces greater weight and fat loss than a placebo. Doses of ephedrine used in research vary, with intakes of less than 20 mg per day considered low, 40—90 mg daily considered moderate, and doses of — mg per day considered high.
Although some positive effects on metabolism and body weight have been seen across a variety of doses, many have questioned the safety of ephedrine. Individual studies have shown mixed results regarding the safety and side effects of this substance across a variety of doses.
Some have reported no significant side effects, while others indicate a variety of side effects that even caused participants to withdraw from the studies 10 , 17 , In-depth reports have combined the results of multiple studies to better understand concerns associated with ephedrine consumption.
One analysis of 52 different clinical trials found no serious adverse events such as death or heart attack in studies on ephedrine — with or without caffeine Yet, the same analysis found these products were associated with a two- to threefold increased risk of nausea , vomiting, heart palpitations, and psychiatric problems. Additionally, when individual cases were examined, several deaths, heart attacks, and psychiatric episodes were potentially linked to ephedra Based on the evidence, potential safety concerns were significant enough to prompt legal action in the United States and elsewhere 1.
While some individual studies did not demonstrate serious side effects of ephedra or ephedrine consumption, mild to highly concerning side effects became apparent upon examination of all available research. While the ephedra herb and products like ma huang tea are available for purchase, dietary supplements containing ephedrine alkaloids are not.
Some ephedrine-containing medications are still available over the counter, though regulations on the purchase of these products can vary by state. For this reason, some dietary supplement manufacturers will market weight loss products that contain other compounds found in ephedra, but not ephedrine alkaloids.
These products may not have the safety concerns observed for products containing ephedrine — but they may also be less effective. While some countries outside of the United States have also banned ephedrine-containing products, the specific regulations vary.
Dietary supplements containing ephedrine alkaloids were banned by the FDA in Medications containing ephedrine and the ephedra plant are still available for purchase, though regulations may vary by location. Ephedrine, one of the main components in ephedra, can boost metabolism and cause weight loss — especially in combination with caffeine. Still, due to safety concerns, dietary supplements containing ephedrine — but not necessarily other compounds in ephedra — are currently banned in the United States and elsewhere.
Your metabolism determines how many calories you burn each day. This is not surprising, considering that the occurrence of such events is likely to be quite rare less than one in a thousand users and the clinical trials included only a few thousand people. However, we found a two- to threefold increase in the occurrence of nausea, vomiting, anxiety, autonomic hyperactivity, and palpitations, and a trend toward an increase in headaches.
We also reviewed descriptions of medical cases published in peer-reviewed journals. This review identified 70 reports of adverse events, including heart attacks, strokes, and serious psychiatric problems. We then obtained all adverse-event reports submitted to the FDA prior to September that were associated with the use of ephedraor ephedrine-containing products and for which records existed: more than 1, adverse-event reports on ephedra and on products containing ephedrine.
Finally, we analyzed more than 18, adverse-event reports received by one of the largest U. These reports had been turned over to the FDA at the request of the U. Deptartment of Justice. Based on the available evidence, these reports were classified as "sentinel events," "possible sentinel events," or lacking in sufficient evidence see Table 1. NOTE: The hour requirement was applied to reports of psychiatric events because these events are believed to result from prolonged use.
The majority of the adverse-event reports lacked sufficient information to demonstrate a connection between the event and use of ephedra or ephedrine. Of particular concern is that half the sentinel events occurred in apparently healthy people under the age of The studies we reviewed suggest that ephedra- and ephedrine-containing products may be modestly effective in promoting weight loss, but the evidence on enhancing athletic performance is not definitive.
However, the use of ephedra or ephedrine does cause an increase in jitteriness, mood changes, palpitations, nausea, and vomiting. Moreover, the adverse-event reports raise serious concerns about the safety of ephedra and ephedrine products. In response to our report, the federal government quickly moved to propose stricter labeling of ephedra products and solicited public comment on whether the safety evidence thus far warrants further restrictions.
By itself, the existing evidence is insufficient to link these products conclusively with death and other serious health problems. However, our analysis of the existing studies and their shortcomings suggests that a more definitive answer to questions about ephedra's safety could be obtained by doing what is called a "case-control" study. Such a study would compare ephedra use by individuals who suffered death or another illness with use by similar individuals who have not suffered severe health problems.
A study of this type could also be used to compare the safety of ephedra-containing supplements and products containing ephedrine. Finally, a case-control study could help answer safety questions quickly, thus avoiding the expense and time that would be needed to conduct a large-scale randomized controlled trial and potentially saving lives.
Paul G. Morton , et al. Shekelle , Mary L. Hardy , et al. RAND research briefs present policy-oriented summaries of individual published, peer-reviewed documents or of a body of published work. Permission is given to duplicate this electronic document for personal use only, as long as it is unaltered and complete. Copies may not be duplicated for commercial purposes.
The RAND Corporation is a nonprofit institution that helps improve policy and decisionmaking through research and analysis. RAND's publications do not necessarily reflect the opinions of its research clients and sponsors. Research Brief Key Findings Ephedra and ephedrine promote modest shortterm weight loss; their long-term effect is unknown.
Ephedrine plus caffeine boosts immediate physical performance for fit young men; there is no evidence that ephedra or ephedrine improves long-term physical performance of athletes or would work for the general public. The authors of one analysis concluded that supplements containing ephedra and ephedrine trigger modest short-term weight loss about 2 pounds per month more than placebo. But none of the 52 trials they looked at lasted more than six months, so there is no evidence to support ephedra use for long-term weight loss.
And no studies were found that evaluated ephedra use for enhancing athletic performance. Data from 50 trials did show, however, that ephedra and ephedrine are associated with 2- to 3-fold increases in psychiatric symptoms such as irritability and anxiety , autonomic symptoms jitteriness, trouble sleeping , upset stomach, and heart palpitations. Study results dashed any claims that dietary supplements containing ephedra or ephedrine can help with long-term weight loss or enhance athletic performance.
It was also been banned from U. As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.
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