While those making big bucks off cannabis sales make claims the products have health benefits, some doctors point to potential harms.

As part of CTV Vancouver's series, Going Green, we asked doctors to weigh in on alleged medical benefits ahead of legalization.

Marijuana is one of the most widely used substances in Canada, but professionals are warning the public that there isn't a lot of research into health implications.

Producers have claimed cannabis can help everything from arthritis to anxiety, and many users say they've seen the results.

But Doctors of B.C. has pointed out that because the substance has been illegal, there haven't been many studies into benefits or effectiveness. There have been case studies for people who've seen the benefits, but research hasn't been conducted on a larger scale.

"There's so much that we have to learn about cannabis," Dr. Eric Cadesky said.

"My advice would be to talk to their doctor and they can discuss all the potential harm."

Emily Jenkins from the University of British Columbia said the nursing community has a different philosophy.

"We say to start slow, to know your product and where you're getting it from," the nursing professor said.

"We try to take a really pragmatic approach...so, what do we need to do to try and reduce harms when people are choosing to use?"

The lack of scientific study means assumptions and urban myths proliferate, making it hard for both policymakers and recreational users to tell fact from fiction.

"We need to make sure we're having open and honest discussions," Jenkins said.

For example, there's broad consensus on the risks to children, but she said fearmongering types of messaging don't work on youth.

Cadesky echoed the sentiment, saying that most doctors' main concern with legalization is use among young people.

"We know that for people who are under 25 and use it, they have brain changes that are actually quite similar to the brains of people with schizophrenia," he said.

However, he said medical professionals know that some strains of cannabis can help with anxiety or depression. But, he said, there might be other treatments that are safer for them.

"I think what's important is that people continue to have an honest relationship with their health care providers, and when we're talking to people about the best decisions that they can make for themselves, that they are giving us the full information so we can make the best decisions together," he said.

Cadesky doesn't recommend smoking any type of plant material, but added that it is important that research is conducted.

"Hopefully with the legalization that will open it so that we can have the proper studies so that we can understand the benefits as well as the harms of cannabis," he said.

With a report from CTV Vancouver's Penny Daflos