Supplements, vitamins and all other alternative medicine have quickly ballooned to a $34 billion a year industry, but the industry has been mired with scrutiny and lawsuits over the lack of proof of its effectiveness. A new book further questions the industry and even says it does more harm than good to those who consume it.

Dr. Paul Offit, a 62-year-old pediatrician at Children's Hospital of Philadelphia and Chief of Infectious Disease, is on a mission to  His most recent book, "Do You Believe in Magic?: The Sense and Nonsense of Alternative Medicine" which debuted Tuesday, takes on the vitamin and herbal supplements industry, and alternative medicine of all kinds, Congress and celebrity doctors who publicize their own products.

According to the National Center for Health Statistics, 50 percent of Americans consumed some sort of dietary supplements in 2003-2006, with 40 percent of them being multivitamins and 10 percent say they use it on their children. Alternative medicine includes everything from herbal supplements to aromatherapy, acupuncture and crystal healing. Consumers are currently flooded with alternative medicines, with over 54,000 varieties currently being sold in stores and the Internet, according to the Food and Drug Administration.

"It's a big business," says Offit. Alternative medicine that is labeled as a "supplement," rather than a "drug" does not have to be approved by the FDA. This makes it hard for consumers to be certain of what is actually in their supplements and whether it's safe to consume.

Some supplements that are proven to be ineffective include St. John's wort supplements which did not relieve depression as advertised, Gingko biloba did not slow mental decline, improve memory or reduce blood pressure and Echinacea did not prevent or treat colds, according to the National Center for Complementary and Alternative Medicine.

The current perception held by most consumers is that supplements and vitamins are healthy and natural. Pharmaceuticals, especially prescription drugs, tend to be perceived as potent chemicals. In other words, the more regulated a substance is, the more dangerous it is perceived to be. Similarly, a substance that almost completely lacks any regulation might appear harmless.

Offit says it unsettles him to see not only ordinary citizens buy into the claims of homeopaths, naturopaths and the vitamin industry, but doctors and hospitals. He calls out Dr. Andrew Weil, Dr. Deepak Chopra and others, saying they have abandoned science for the thrill of celebrity that goes with evangelizing alternative medicine.

"They have this almost guru-like stature that you should listen to them," Offit says. "It is the surety of their statements that draw you to them. They make you think they are someone who just knows. But it should be the strength of data, the strength of science, rather than personality, that decide what it is true."

However, there are some therapies and supplements that have been proven effective. Acupuncture relieves pain and chemotherapy-induced nausea, mindfulness meditation reduced stress and pain, Tai chi improved balance in patients with Parkinson's disease, and clinical hypnosis reduced post-menopausal hot flashes, according to a report by USA Today.

Offit is best known for address vaccine doubters - people who worry that vaccinations might somehow harm children and whose fears culminated in a wave of support for the argument that childhood vaccines can cause autism. Celebrities, like former Playboy model, Jenny McCarthy, singer Britney Spears and actor Charlie Sheen, have all have all come forward to support the anti-vaccination movement.