Xenadrine is a weight-loss supplement that has had several different formulas over the years in an effort to create a formula that is both safe and effective. There is limited and conflicting evidence on the weight-loss benefits of the current main ingredients in Xenadrine, however, so it may not greatly increase your weight-loss results without diet and exercise changes as well.
The original Xenadrine formula included ephedra, which was somewhat effective for weight loss but has since been banned due to safety concerns. Another previous version included green tea extract, bitter orange and yerba mate, but there were concerns that bitter orange might have a similar effect as ephedra, so some weight-loss supplements have removed this ingredient from their formulas. The current formula includes wild olive, cormino, frauenmantle and horsemint, with some versions also containing raspberry ketones, garcinia cambogia and green coffee. It contains caffeine as well.
Effect of Caffeine
Caffeine can help increase your energy expenditure, according to a 2004 study published in the American Journal of Clinical Nutrition. This means it may have at least a small effect on weight loss. Xenadrine is quite high in caffeine, with 180 milligrams per dose. If you take it before each meal as suggested by the manufacturer, you'll be consuming quite a lot of caffeine per day, which might cause side effects, especially if you're sensitive to caffeine. Too much caffeine can cause headaches, nausea, drowsiness, vomiting, tremors, trouble sleeping, anxiety, depression, a fast heartbeat and an increased risk for osteoporosis.
Potential Effect of Other Ingredients
Although the Xenadrine website mentions studies showing the benefits of their formula for weight loss, these aren't readily available online.
Although a few small studies have found an increase in weight loss with garcinia cambogia, some higher-quality studies that were randomized and used a placebo didn't find weight-loss benefits for this herb, according to a review article published in Critical Reviews in Food Science and Nutrition in 2012. Another review article, published in Evidence-Based Complementary and Alternative Medicine in 2013, came to a similar conclusion, noting that study results are conflicting, with some negative and some positive results for garcinia cambogia and weight loss.
An animal study published in Human Health and Biomedical Engineering in 2011 found that raspberry ketones may improve insulin resistance and have an anti-obesity function. More research is necessary to show whether raspberry ketones have the same effect in people.
A study published in Clinical and Experimental Hypertension in 2006 found no weight-loss benefits from green coffee bean extract but did find that it lowered blood pressure levels.
A Healthier Choice
It's healthier, and you're likely to get better weight-loss results, if you increase your physical activity and follow a nutritious, reduced-calorie diet before you consider any weight-loss supplement. The University of Illinois at Urbana-Champaign recommends cutting calories by limiting the amount of sweets, fatty foods and products made with refined grains that you eat, while still getting plenty of fruits, vegetables and lean proteins.