A number of people who have seen advertisements and anecdotal reports for Plexus Slim®, a weight loss supplement, have been smartly asking, “Is Plexus safe?” To answer this question, this article briefly reviews the known information about Plexus Slim®, including the ingredients, their amounts, and what research has been done on either Plexus itself or on its individual ingredients.
Is Plexus safe based on testing and research?
When evaluating the safety of a dietary supplement like Plexus, it is important to know whether the supplement itself has undergone any testing and if so, what kind(s). Ideally, for evaluating safety, it would be best to see that Plexus itself has not only undergone testing in humans, but that the testing was done in a randomized, double-blind, placebo-controlled trial in which both safety and efficacy were evaluated and the results were published in a peer-reviewed medical journal.
While this level of research certainly exists for many supplements and natural ingredients, it was not done for Plexus. On the web page for Plexus Slim® ingredients, Plexus Worldwide states, “Its effectiveness has been clinically proven.” However, they do not reference this claim and they do not provide any additional information on their website to support it. A search of all the general databases for published medical research, including PubMed and Google Scholar, does not turn up any citations for studies on Plexus Slim® or on any product containing its proprietary blend of ingredients.
Since no published, human clinical studies evaluating the safety and efficacy of Plexus Slim® seem to have been conducted, there are some additional important questions that must be asked when evaluating its safety. First, are the ingredients in Plexus Slim® product safe to consume at the recommended dosage level based on human studies? In other words, has each individual ingredient in Plexus been tested in human studies for safety? Second, if no human studies on the individual ingredients have been done, have there been any animal or laboratory toxicity studies done on Plexus Slim’s® individual ingredients? And third, does Plexus contain what it says it does and nothing more/nothing less? In other words, Plexus could be unsafe if what is listed on the label does not reflect what is actually in the product because of contamination or adulteration.
As you might expect, none of these questions about the safety of a supplement like Plexus Slim® are easily answered, nor are the answers black and white. Nevertheless, let’s take a look at the ingredients listed on the Plexus label and try to answer these important questions about the supplement’s safety.
What is Plexus?
“Plexus Slim®” is a weight loss supplement manufactured by the network marketing company Plexus Worldwide, Inc. According to Plexus Worldwide’s website (accessed on February 19, 2014), each 5.0 gram serving (1 stick pack) of Plexus Slim® contains the following ingredients. (Note: Plexus Worldwide, Inc. provides no actual image of the Plexus Slim® product label on their website, so the manner in which the ingredients and their amounts may be listed on the current Plexus Slim® label are not available for the public to review.)
One 5.0 gram serving (1 stick pack) of Plexus Slim® contains:
1. Chromium……………..(amount and form of chromium not listed on website)
2. Proprietary blend….(amount not listed on website)
Chlorogenic Acid (from Green Coffee Caffea arabica Bean) Extract (contains less than 2% natural caffeine)
Garcinia cambogia fruit extract
Alpha Lipoic Acid
Hoodia gordonii whole plant extract
3. Other Ingredients: Polydextrose, Citric acid, Natural flavors, Beet (Beta vulgaris root) extract (for color), Stevia (Stevia Rebaudiana Leaf) extract, Luo han guo (Siratia grosvenorii fruit) extract.
Is Plexus safe based on the ingredients and their amounts as listed on the Plexus Slim® label?
While Plexus Worldwide, Inc. provides a list of ingredients in Plexus Slim® on their website, they do not provide the amounts of the individual ingredients. From the information provided, it is known that each serving contains 5 grams of total ingredients, including chromium; a proprietary blend of plant extracts and alpha lipoic acid; and the “other ingredients” which consist of plant extract-based sweeteners, natural flavors, citric acid and polydextrose. Without knowing the dose of each of the ingredients in the proprietary blend it is difficult to comprehensively evaluate them for safety. Nevertheless, it is still useful to review the scientific literature for safety information on each of the individual ingredients.
Is Plexus safe based on the chlorogenic acid it contains?
Plexus claims that chlorogenic acid from green coffee extract is one of Plexus Slim’s® primary active ingredients. In 2011, researchers from the University of Exeter in the UK published a systematic review and meta-analysis of randomized clinical trials examining the efficacy of green coffee extract supplements for weight loss. According to the study authors, all of the trials conducted up to that point had been of very short duration, making it difficult to assess the safety of green coffee extract for medium to long-term. “Although none of the randomized controlled trials identified reported any adverse events, this does not indicate that green coffee extract intake is ‘risk-free’… the safety of this weight loss aid is not established,” they concluded.
Since then, another small, controlled clinical trial was conducted to evaluate the efficacy and safety of a green coffee bean extract in overweight subjects using higher daily dosages than previous studies (700 to 1050 mg vs. 180 to 400 mg). As with previous studies, there were no side effects or adverse effects based on measurements of heart rate and blood pressure.
In these human studies, green coffee extract used for short periods of time (less than 16 weeks) appears to be safe. However, the studies did not look comprehensively at the subjects’ blood and urine for signs of adverse effects such as kidney or liver damage or elevated biomarkers for cardiovascular disease. An earlier study found that a daily dose of 2000 mg chlorogenic acid caused significant increases in subjects’ homocysteine levels. Elevated homocysteine levels increase the risk of heart disease. While it is highly unlikely that 1 or 2 daily servings of Plexus contains more than 2 grams of chlorogenic acid, it is possible that even- lower levels of chlorogenic acid could have negative effects on homocysteine levels and thus potentially raise the risk of heart disease in some individuals.
Is Plexus safe based on the Hoodia it contains?
Another ingredient Plexus Slim’s® proprietary blend is Hoodia gornonii extract. Hoodia is a plant native to parts of Africa that was traditionally eaten as a food to suppress appetite. Today, extracts of the plant are sold as weight loss supplements, despite only one small human study using Hoodia extract having been published.The results showed that a total of 2220-mg perday caused episodes of nausea, vomiting, and disturbances of skin sensation. More concerning, however, was that it significantly increased blood pressure, pulse, heart rate, and markers of liver dysfunction. It is unlikely that Plexus Slim® contains Hoodia extract in this dose range (2220 mg), but there is no way to know for sure based on the information provided on their website. And whether lower dosages also cause adverse effects in humans is simply not known. Therefore, the presence of Hoodia extract in Plexus Slim® in any amount could potentially be unsafe.
Is Plexus safe based on studies for contamination and adulteration?
Adulteration of weight loss supplements with pharmaceuticals and other banned and dangerous ingredients is, unfortunately, rampant. The FDA keeps a growing tally of weight loss products contaminated with undeclared drugs and/or chemical ingredients. The FDA’s laboratory tests have revealed the presence, for example, of sibutramine and phenolphthalein in a number of tainted weight loss products being sold over-the-counter. Phenolphthalein is laxative drug banned by the FDA in 1999 for potential cancer risks. Sibutramine is a controlled substance and the active pharmaceutical ingredient in Meridia, an approved prescription drug to treat obesity. Some of the –tainted products tested by the FDA recommend taking more than 3 times the recommended daily dosage of sibutramine, putting consumers at risk of serious adverse effects such as increased blood pressure, tachycardia, palpitations, and seizure. While Plexus Slim® has not been identified on the FDA’s list, the FDA’s tally contains only a tiny fraction of products on the market. Can the company prove with independent lab testing that Plexus Slim® does not contain these adulterants or others?
Finding safe, effective supplements for weight loss
Ideally, individuals interested in supplements for weight loss should work with a practitioner trained in nutritional and botanical medicine who stays up-to-date with the scientific literature and has experience and knowledge with choosing and prescribing only the highest quality supplements. Supplement companies who take quality assurance and manufacturing practices very seriously will test all raw materials and finished products for purity and potency using scientifically-valid test methods, and their supplements will be manufactured in FDA-inspected facilities and/or in facilities that exceed the FDA’s good manufacturing practices. They will also disclose the amounts of each ingredient or the total amount of a propriety blend.
On their website, Plexus Worldwide provides very little information about their quality assurance protocols or manufacturing practices, – leaving questions about whether Plexus Slim® is tainted or contaminated, and they do not disclose the amount or form of the chromium or the propriety blend. Because of these issues and more, it is not easy to definitively know whether Plexus Slim® is safe or not. Supplements can be incredibly effective tools for health and wellness, but it is best not to guess or take chances on supplements that do not disclose even basic information about ingredient sources, their amounts, quality control, and manufacturing practices. Do your research and stay safe and healthy!