Whether it's diet products, teeth whiteners, or even an IQ test that links back to your cell phone, many Canadians have been caught by questionable internet advertising -- often through social networking sites.

A quick poll of people on Vancouver streets found other examples.

"[The ads say] it's ‘totally free' and then they charge your credit card 90 bucks," one woman said.

"It's a ‘miracle' this or a ‘miracle' that -- ‘you are going to lose 20 pounds in four days,'" another said.

The big claims are easy to find, as are the 14-day "free" trials. But what's harder to locate is the fine print showing how much you'll be charged.

The rules that apply to other advertising just don't seem to apply on the internet, but they should.

Mike Shekhtman's courier company, Eeko Couriers, is a social media advertiser, using sites like Twitter, Linkedin and Facebook to get his brand out. He thinks it's time to clean up misleading ads in social media.

"It's a good way for con artists to take advantage of anything that is popular. That's going to reach millions of people, even if it's one per cent, it's a lot of revenue that they are generating," Shekhtman said.

The Better Business Bureau fields hundreds of complaints about internet advertising every year.

"It's an environment that needs to be investigated to see who's behind it," the BBB's Lynda Pasacreta said.

Canadian authorities agree. Canada's consumer watchdog has announced a crackdown on false and misleading ads on social networking sites.

The assistant deputy commissioner of the Competition Bureau, Brent Homan, told CTV News that as 16 million Canadians are active users of those sites it is an area that needs to be investigated.

Backed by tough new laws, Canada's Competition Bureau is teaming up with law enforcement agencies in 40 countries to sweep social media sites. And when they find misleading ads, Homan said they will send them notices to try and get "voluntary compliance."

That doesn't sound like much until you look at what happened with Project False Hope, a similar sweep to shut down fraudulent cancer treatment claims.

The Competition Bureau got more than 100 sites in Canada to tone down their claims. And in the most extreme case, an Edmonton man was sent to prison for 33 months and fined more than $100,000. Victims got their money back.

Under Canada's newly increased penalties, first time offenders can be fined up to $750,000. Corporations can be fined up to $10 million. Repeat offenders can be fined up to $1 million, and repeat corporations up to $15 million.

Courts can also order restitution and can seize assets. And international cooperation means advertisers can't hide behind borders to target consumers.

But the best advice is be skeptical of the advertising you see on the internet.

"If the first time you hear about a scientific breakthrough is on the internet you should be suspect. Authentic scientific breakthroughs generally make headline news," Homan said.

With a report from CTV British Columbia's Chris Olsen