People with chronic and terminal illnesses are increasingly turning to crowdsourcing to raise money for experimental stem cell treatments, but a University of Minnesota researcher has found they often use unproven or overly optimistic claims in their pleas.

Associate bioethics professor Leigh Turner also found a direct pipeline from the medical companies — and the language they use to promote stem cell treatments that have not yet been proven through research — to the patients and their appeals.

Examining 408 campaigns on the GoFundMe and YouCaring websites, Turner and colleagues found that more than half made definitive statements about the effectiveness of unproven stem cell therapies provided by 50 companies.

Turner’s findings, published Tuesday in the Journal of the American Medical Association, found another 30 percent that made claims deemed at least optimistic about the therapies.

Only 36 of the campaigns mentioned the risks of proposed therapies, but they mostly stated that the risks were lower than those of standard treatments of their conditions.

Optimistic claims could help people raise money for these direct-to-consumer stem cell treatments, which generally aren’t covered by health insurance. Turner said that he sympathized with patients who are desperate in their efforts to treat incurable conditions, but that their claims don’t represent science-based treatment or a wise use of money.

Individual success stories are featured on company websites, but Turner said the failures are never revealed.

“A lot of these businesses, the messages they are putting out there are very much anecdote driven and testimonial driven,” Turner said. “If that’s their evidence base, I have a hard time taking them all that seriously.”

The conditions for which patients were seeking treatment included a range of serious and chronic illnesses, from Amyotrophic Lateral Sclerosis (ALS) to Chronic Obstructive Pulmonary Disease (COPD).

While stem cell transplants have been tested and approved by the U.S. Food and Drug Administration for the treatment of certain cancers and blood disorders, organizations such as StemGenex or the Lung Institute have broadened their use to a range of other conditions, Turner said. For example, he said, there is no proven cure for COPD, which severely reduces airflow in the lungs, but some stem cell companies are promoting their treatments as alternatives.

Turner noted that some private stem cell therapy companies even offer tips on how to raise money via crowdsourcing. “You can track those unsubstantiated … claims back to the businesses themselves,” he said.

The companies “have YouTube channels, Facebook pages, Twitter feeds. They do a lot to kind of pump these messages out,” Turner said. “It’s marketing. It’s not education. It’s not science driven.”

Federal regulation of marketing claims for stem-cell therapies is somewhat vague — a fact noted by the companies — but the FDA has started to scrutinize their marketing practices.

In an advisory last year, the agency said “don’t believe the hype” and urged people to restrict themselves to stem cell therapies that have been FDA approved or are part of an approved clinical trial or investigational treatment.

Crowdsourcing sites post legal waivers listing them as platforms for campaigns but not responsible for their accuracy. E-mails to GoFundMe and YouCaring regarding the stem cell study were not returned.