You may have heard about the miraculous healing powers of stem cell therapy. Clinics are springing up everywhere offering treatments. Desperate consumers are willing to spend thousands of dollars for relief or a cure to what ails them.

However, regulators and some health experts advise caution. While stem cell therapy has shown promise for treating some complicated diseases, there is still a lot to be learned and many treatments are experimental.

Stem cell treatments are only widely accepted to treat blood disorders like leukemia, some forms of anemia and in some cases, burn victims.

To date, Health Canada says it has granted market authorization for only one stem cell therapy, Prochymal, used for actute graft- versus- host disease. 

Recently, a full page ad appeared in Vancouver offering free seminars to B.C. residents regarding stem cell therapy to treat knee pain and various other joint conditions. It was from an American group trying to generate business for their clinic in Bellingham.

CTV News talked to some people who attended one of the seminars in downtown Vancouver.

“I've come because I have a disc problem," said Marge, who did not want her last name used.

"I'm about to ask the fellow afterwards if they treat things like COPD," said Klaus Mueller.

Stem cell therapy has not been proven to treat Chronic Obstructive Pulmonary Disease.

Maureen Rosen, who suffers from COPD, paid a Florida clinic for stem cell therapy to treat her symptoms. 

“That $7,000 we spent was like throwing it in the trash,” she said.

Research has shown stem cell therapy has been effective with some cartilage repair and the FDA encourages research and development of stem cell products to treat various conditions, but only approved products, or those designated as an investigational new drug, IND, can be used on humans.

And the FDA advises patients to ask to see the approval letter for the treatment being considered.

Click her for clinical trials information in the U.S.

Click here for clinical trials database in Canada

The FDA is cracking down on companies and clinics that don’t follow the rules. It recently sent warning letters to two companies about putting patients at risk with unapproved stem cell products.

Patients in Arizona, Florida and Texas suffered from bacterial infections after getting unapproved stem cell shots contaminated with E. coli and other bacteria. 

And U.S. lawsuits are now being filed by patients against clinics that made promises they couldn’t deliver on and in some cases by patients who’ve been harmed. 

|Related: Dozens of clinics in Canada offer unproven stem cell treatments|

CTV News made several requests to the company that placed the full page ad for stem cell seminars in Vancouver, to talk about the stem cell treatments the clinic offers, but got no response. Those who attended were offered a free consultation and told CTV News the stem cell treatments were costly.

“$6,880 for the first and $4,000-something for the second,” said Marge.

"Clinical trials for stem cells don't usually have flashy advertisements, don't promise to be a cure all and shouldn't cost you big bucks," said Lauren Friedman, Consumer Reports health editor.

“I’ve certainly heard from lots of people and friends of mine that have done it, who’ve had amazing results,” said Mueller.

“There’s controversy on everything. My girlfriend and her husband have both gone and they’ve had very good results,” added Marge.  

Health Canada told CTV News that it is following up with the American company advertising stem cell therapy to make sure it is in compliance with regulations, including those related to advertising in Canada.