Aloe vera plants. (Daniel Acker/Bloomberg News)

Aloe vera — the spiky green succulent found in warm climates around the world — has long been touted as a remedy for a range of ailments. Almost none have been verified, but that hasn’t stopped companies from bottling the plant’s juices and selling them as commercial topical gels in major pharmacies and retailers.

The list of purported benefits is long. People typically use aloe gels to treat burns, frostbite and sores, and some claim it can relieve heartburn, lower blood pressure and even slow the growth of breast cancer. The National Center for Complementary and Integrative Health says there’s not enough evidence to support any of that.

Now, there may be another reason to be skeptical of bottles touting aloe. Bloomberg reports that lab tests it recently commissioned showed “no indication” that store-brand aloe gels purchased from Walmart, Target and CVS contained the plant’s juices. A fourth gel from Walgreens tested positive for one of three “markers” that indicate the presence of aloe, but not the other two, the results showed. On their ingredients labels, all the products listed aloe barbadensis leaf juice, Bloomberg reported.

According to Bloomberg, the tests found:

Aloe’s three chemical markers — acemannan, malic acid and glucose — were absent in the tests for Walmart, Target and CVS products conducted by a lab hired by Bloomberg News. The three samples contained a cheaper element called maltodextrin, a sugar sometimes used to imitate aloe. The gel that’s sold at another retailer, Walgreens, contained one marker, malic acid, but not the other two. That means the presence of aloe can’t be confirmed or ruled out, said Ken Jones, an independent industry consultant based in Chapala, Mexico. . . .

The four gels that Bloomberg had analyzed were Wal-Mart’s Equate Aloe After Sun Gel with pure aloe vera; Target’s Up & Up Aloe Vera Gel with pure aloe vera; CVS Aftersun Aloe Vera Moisturizing Gel; and Walgreens Alcohol Free Aloe Vera Body Gel. The lab that did the testing requested anonymity to preserve its business relationships.

The report comes as alternative medicines and “natural” products have come under increased scrutiny from regulators, and the findings could strike a blow to the market for aloe products, which include gels, creams, vitamin tablets and drinks. The U.S. market for aloe vera products grew 11 percent last year to $146 million, according to Bloomberg.

Fruit of the Earth, a company that makes gels for Walmart and Target, and its supplier, Concentrated Aloe Corp., both disputed the test results, according to Bloomberg.

“We’ve been in the business a long time and we know where the raw ingredients come from,” Fruit of the Earth general counsel John Dondrea said. “We stand behind our products.”

CVS defended the gels in a statement to CBS News.

“We are committed to bringing high quality products to consumers, and maintain ongoing contact with suppliers to ensure that they meet our high standards,” CVS said. “We have reviewed with the supplier, and they have affirmed the product’s authenticity.”

Walmart gave a similar statement to Mashable.

“We hold our suppliers to high standards and are committed to providing our customers the quality products they expect,” a Walmart spokesperson said. “We contacted our supplier and they stand behind the authenticity of their products.”

Walgreens told Bloomberg their aloe suppliers verified that their products contained the plant. A Target representative was not immediately available for comment Tuesday; the company declined to comment in Bloomberg’s story.

The U.S. Food and Drug Administration doesn’t have much leverage to regulate aloe vera products, which don’t require agency approval to be sold at retailers. The Fair Packaging and Labeling Act requires companies to list ingredients on cosmetic products, but the FDA doesn’t review that information before the products appear in stores. The Food Drug and Cosmetics Act does, however, prohibit false or misleading labeling.

Some consumers have already gone to court to challenge the ingredients in aloe vera products. Lawsuits seeking class action status are pending against the four pharmacies and Fruit of the Earth, claiming the products contain no aloe vera at all.

Attorneys in one lawsuit wrote: “No reasonable person would have purchased or used the products if they knew the products did not contain any aloe vera.”

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