There is a growing national movement to rethink marijuana use. Some experts believe marijuana is a beneficial plant that might play a primary role in cancer treatment and prevention. Opponents say it is a dangerous “gateway” drug that leads to more serious narcotic use and will undermine our social fabric.

Voters in five states—Oregon, Washington, Arizona, South Dakota and California—and 21 U.S. cities across the country, will consider new ballot initiatives to decriminalize or legalize marijuana for medical and or adult recreational use in November. Since 1996, 14 states and the District of Columbia have enacted medical marijuana laws.

Until 1937, marijuana, whose botanical name is cannabis, was a widely used remedy for all sorts of ailments from nausea and anxiety to epilepsy and colicky babies. Chances are good your great grandmother used Cannabis indica for labor pains, like many generations of women before her.

Clinical trials conducted by the American Marijuana Policy Project, a marijuana advocacy group, show cannabis to be an effective treatment for cancer and AIDS patients who often suffer from clinical depression, nausea and resulting weight loss due to chemotherapy and other aggressive treatments. While doctors in states without legalized medical marijuana laws can’t prescribe its use, they can legally recommend marijuana therapy to a patient—and many do.

Is America’s opinion of cannabis changing? Consider this:

In July 2010, the Department of Veterans Affairs announced that patients treated at its hospitals and clinics can use medical marijuana in states where it is legal, a policy clarification that veterans have sought for several years.

On the website America Speaking Out, Congressional Republicans asked the public to be part of “building its new governing agenda.” Decriminalizing and or legalizing marijuana use was among the highest ranking idea submitted in the “American Values” category.

The Teamsters added 40 new members to their roll this month by organizing the nation's first unionized group of marijuana growers.

Dr. Andrew Weil, founder and director of the Arizona Center for Integrative Medicine, wrote last week in a Huffington Post column about cannabinoids' “immense therapeutic potential.”

Weil cites a number of scientific studies show that tetrahydrocannabinol or THC in cannabinoids (chemical constituents of cannabis) inhibit tumor growth in laboratory animal models. THC appears to lessen the formation of new blood vessels required for tumor growth, and in some cases, it has killed the tumor without affecting surrounding cells unlike traditional cancer treatments.

“If these findings hold true as research progresses, cannabinoids would demonstrate a huge advantage over conventional chemotherapy agents, which too often destroy normal cells as well as cancer cells,” Weil wrote.

A Canadian study, one of the first to conduct randomly controlled clinical trials, tested if smoked marijuana actually had pain relieving properties. Medical marijuana, and its active ingredient THC, is often prescribed to control chronic pain.

Dr. Mark A. Ware, a pain researcher at McGill University in Montreal and lead researcher said chronic pain suffers, including those who suffered from persistent nerve damage found mild pain relief — without getting high — by taking just a puff of marijuana three times a day. Nerve damage patients in the study who did not respond to other pain relieving remedies reported sleeping better and feeling less anxiety. The study was published in the August 2010 edition of The Canadian Medical Association Journal.

However, not everyone agrees cannabinoids should be moved back into the mainstream of therapeutic remedies. Dr. Eric Braverman, medical director of a multispecialty clinic in Manhattan told the New York Times that legalizing marijuana was "unnecessary and dangerous" since Marinol, a prescription pill form of marijuana's active ingredient THC, approved by The Food and Drug Administration in 1985, is readily available and provides the medicinal effects of the plant. ''Our society will deteriorate,'' he said.

Lynette Summerill is an award-winning writer who lives in Scottsdale, Arizona. In addition to writing about cancer-related issues, she writes a blog, Nonsmoking Nation, which follows global tobacco news and events.