HOUSTON -- Note: The following story is a verbatim transcript of an Investigators story that aired on Tuesday, July 22, 2008, on KPRC Local 2 at 10 p.m.

Local 2 Investigates claims that indoor tanning can help prevent cancer. You've probably seen the billboards and commercials advising you to "get your fix of vitamin D."

The Texas Department of State Health Services has seen them, too, and it said the ads might be illegal. Investigative reporter Amy Davis reveals the truth behind the health claims that could have the Houston company in hot water.

On a visit to Memorial Park, we took a very unscientific poll, asking people what comes to mind when they hear the words "tanning bed."

"I think of cancer," said a woman named Julie, almost instantly.

"Uh, that you're going to get cancer," said Claire Martin, as if the answer were obvious.

Another woman told us the words made her think "wrinkles."

The negative connotations of tanning beds are fairly universal, but the owner of Darque Tan, one of the largest tanning salon chains in the country, wants you to think something else.

"You want to change it so that when people think tanning beds, they think what?" Davis asked Robbie Segler, the owner of Darque Tan.

"Vitamin D," answered Segler.

References to vitamin D have become a part of every Darque Tan commercial and billboard.

And when you hear what we found with our hidden cameras, it seems it's also part of the sales pitch.

One Darque Tan employee at the store on the corner of Richmond and Chimney Rock told a KPRC intern wearing a hidden camera, "People that have high levels of vitamin D, they sometimes, you know, are not as likely to get cancer."

Studies show vitamin D, found in milk and UV rays among other sources, reduces your risk of internal cancers.

So Robbie Segler said tanning beds that also emit UV rays can also help prevent cancer.

"If you're deficient in vitamin D, you are now doubling your chances of dying from cancer, heart disease and auto immune disease," said Segler.

"I simply think this is all about making money for the tanning industry and that's the bottom line here," countered Dr. Adelaide Hebert, a dermatologist with the University of Texas.

Local 2 Investigates learned the claims could actually cost Darque Tan because the Texas Department of State Health Services contends the ads and the comments we caught on hidden camera are a violation of the Texas Health Code.

Chapter 145 of the code reads, "A tanning facility operator may not claim or distribute promotional materials that claim that using a tanning device is safe or free from risk or that using a tanning device will result in medical health benefits."

We obtained a warning letter the state sent to a San Antonio Darque Tan in April after the state says the facility gave out promotional cards that displayed the health claim "vitamin D."

But when Davis asked, Segler said his company does not make health claims.

"And Darque Tan is not violating the Texas Health Code?" asked Davis.

"Absolutely not," said Segler.

At this point, Segler had no idea that we sent interns, wired with hidden cameras, into five Houston Darque Tan stores.

At the Meyerland location, a woman behind the counter said, "Vitamin D is just healthy for your skin. Just really like about 5 minutes in a level one bed a day, if you're looking for like a vitamin D efficiency, then that's what you would need to have to get a source of vitamin D to help with the internal cancers and stuff like that."

We got the most elaborate explanation from a Darque Tan employee at the River Oaks location.

"A thousand people die a year from skin cancers, OK?" the man told our intern. "And 175,000 people die from internal cancers -- prostate cancers and ovarian cancers and things like that. And it's been proven in books and medicine and stuff like that that vitamin D, however you get it, helps prevent those internal cancers. So would you be more worried about the skin cancer on your arm and being able to have it laser cut out or whatever like that or would you rather have ovarian cancer that you can't get rid of and you people die from?"

"Are either one of those health claims?" Davis asked Segler after showing him the clips.

"They are health claims, but certainly the reporter is pitching them a question about that connection," Segler said.

He claimed most customers don't ask his employees pointed questions about the vitamin D ads.

"If you were to solicit a health-related question, I would assume you'd get a health-related answer," Segler explained.

Violating the state health code governing tanning facilities could cost Darque Tan its license.

Doug McBride of the Department of Health Services said, "penalties can be administrative, civil or criminal and may include fines not to exceed $25,000 per day per offense."

McBride's office referred the case to the Attorney General for review.

"That, to me, is a basic denial of free speech," Segler said of the health code that prohibits him from talking about the link between vitamin D and his tanning beds.

He said he feels so strongly that tanning beds can save lives by decreasing the risk of internal cancers, he will take this issue "as far as the state wants to take it."

Segler says the risk of skin cancer is so slight, it's worth the decrease in risk customers might receive of getting other types of cancer.

"We would never in good conscious recommend that a patient go to a tanning bed," Hebert told Local 2 Investigates.

"With all due respect to the dermatologists, dermatologists know nothing about vitamin D metabolism," Segler countered.

Instead, he points to recent studies that show Vitamin D is a critical tool in fighting internal cancers.

Dr. Joan Lappe conducted one study at Creighton University in Omaha, Nebraska.

When we told Lappe that Segler cited her study to promote indoor tanning, she said there aren't enough studies on tanning beds to make the safe connection between indoor tanning and vitamin D.

"There's a great big leap from going from my study to going to tanning booths are good sources of vitamin D," Lappe said.

We also checked with researchers at Harvard and Boston universities who all say it's true increased levels of vitamin D does decrease your chances of getting cancer, but none of them said they would or have ever advocated using a tanning bed to get your vitamin D.

They all recommend foods such as milk or taking supplements.

The Darque Tan ads are still under review by the Attorney General's Office. We'll let you know what, if any, action they take.

Statement From Harvard University's Dr. Edward Giovannucci:

"It is true that there is some evidence that higher vitamin D levels may reduce cancer risk, particularly of colorectal cancer, and possibly some other cancer types. The data a relatively strong, but not considered definitive by everyone.

"A meta-analysis of randomized trials of vitamin D vs. placebo found an overall 8 percent lower total mortality in those who got vitamin D. Thus, overall, there is strong evidence that more vitamin D may have some important health benefits, perhaps even beyond cancer.

"To my knowledge, there is no direct evidence that tanning booth use is related to lower cancer risk, but if the tanning booth supply UV-B, vitamin D levels should increase in general.

"I don't know what the regulations are (if any) regarding the types and amount of radiation from tanning booths. It is also important to note that if there truly is benefit to having higher vitamin D, the vitamin D could be gotten in a supplement, though probably at higher levels than are available generally in most supplements. The potential downsides of UV radiation also need to be taken into account."

More Information:

National Institutes of Health Vitamin D Fact Sheet
USA Today: Vitamin D Research May Have Doctors Prescribing Sunshine