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?” and “Are there Plexus dangers I should understand?”

To answer these questions, we consider the broader question “What is Plexus?” by looking at known information about Plexus Slim ingredients and their amounts along with Plexus Slim side effects.

We also cite Plexus reviews and address the question of whether there are any known dangers associated with Plexus products.

Is Plexus Safe, Based on Testing and Research?

When evaluating the safety of a Plexus diet supplement, it’s 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 does not exist for Plexus Slim. The company, Plexus Worldwide, claims on its website that “Its effectiveness has been clinically proven.” However, the company does not reference this claim and does not provide any additional information on its website to support it.

A search of all of 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.

Is Plexus Safe? Important Questions and Considerations

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 products 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.

What Is Plexus?

So what is Plexus? Plexus weight loss supplements are manufactured by the network marketing company Plexus Worldwide Inc., sometimes known as the Plexus pink drink. According to Plexus Worldwide’s website (accessed on Aug. 13, 2015, Aug. 26, 2016, Jan. 11, 2017, April 24, 2017, and Nov. 9, 2017), each serving (1 “Slim Pack”) of Plexus Slim ingredients contain the following:

200 mcg chromium (as chromium polynicotinate)

1,000 mg of xylooligosaccharides

531 mg of a proprietary blend of: Green coffee bean extract (containing an unknown, unlisted amount of chlorogenic acid and less than 2 percent natural caffeine) Garcinia cambogia fruit extract Alpha lipoic acid

Other ingredients: polydextrose, citric acid, natural flavors, beet extract (for color), stevia leaf (Stevia Rebaudiana) extract, luo-han-guo fruit extract, guar gum, silicon dioxide

Are These Plexus Slim Ingredients Safe?

While Plexus Worldwide provides a copy of Plexus Slim’s label on its website that lists the product’s ingredients, it does not provide the amounts of all of the individual ingredients because some of them are part of a proprietary blend. So although Plexus discloses the total amount of all the ingredients within the proprietary blend (530 mg per serving), it does not disclose the individual amounts of each ingredient, which makes it difficult to determine any Plexus dangers.

Without knowing how much of each ingredient is contained in each serving, it is difficult to comprehensively evaluate Plexus Slim’s individual ingredients for safety. Nevertheless, it is still useful to review the scientific literature for whatever safety information is available.

Is Plexus Safe Based on the Green Coffee Extract it Contains?

Plexus Worlwide claims that a derivative of chlorogenic acid from green coffee extract is Plexus Slim’s primary active ingredient.

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. [1] 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). [2] 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 2,000 mg chlorogenic acid caused significant increases in subjects’ homocysteine levels. [3] Elevated homocysteine levels increase the risk of heart disease. While we don’t know exactly how much chlorogenic acid is in Plexus pink drink because the company chooses not to disclose that information, we do know—given that the proprietary blend contains 530 mg—that it cannot contain more than 2 grams of chlorogenic acid. However, 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 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 three times the recommended daily dosage of sibutramine, putting consumers at risk of serious adverse effects such as increased blood pressure, tachycardia, palpitations, and seizure. Plexus Slim has not been identified on the FDA’s list, but the FDA’s tally contains only a tiny fraction of products on the market. Can the company prove with independent lab testing that Plexus pink drink does not contain these adulterants or others?

Finding Safe, Effective Supplements for Weight Loss

Ideally, individuals interested in Plexus products 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 its website, Plexus Worldwide provides very little information about its quality assurance protocols or manufacturing practices, leaving questions like ‘is Plexus safe?’ not fully answered while creating skepticism about whether or not Plexus Slim is tainted or contaminated. Because of these issues, it’s not easy to conclude definitively 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 from companies that don’t disclose even basic information about ingredient sources, their amounts, quality control, and manufacturing practices. So before consuming, consult your doctor before taking any Plexus supplements to discuss any side effects.

Share your Plexus reviews and experiences in the comments section below.

Learn more about the safety of other popular weight loss options in these articles:

This article was originally published in 2014 and is regularly updated.

[1] Gastroenterol Res Pract. 2011; 2011: 382852.

[2] Diabetes Metab Syndr Obes. 2012; 5: 21–27.

[3] Am J Clin Nutr. 2001 Mar;73(3):532-8.

[4] Am J Clin Nutr. 2011 Nov;94(5):1171-81.