The wizard is a fraud.

Thats what Dorothy and her friends discover in The Wizard of Oz.

Many viewers of The Dr. Oz Show will have reached a similar conclusion last week, following another one of the hosts silly attacks on genetic modification in agriculture as well as his ongoing support for costly and pointless warning labels on ordinary food.

Pendant des années, Mehmet Ozthe full name of this talk-show celebrityhas waged a propaganda campaign against GMOs, suggesting that eating food with these conventional ingredients poses health risks.

Its about as truthful as a nature documentary on flying monkeys.

Although Oz exploits his standing as a medical doctor, the American Medical Association disagrees with him: It has said that food made with GMOs is perfectly safe. So has every other group that has studied the question, from the UNs World Health Organization to the U.S. Food and Drug Administration.

From a scientific standpoint, the safety of eating GMOs is a settled question. Anybody who claims otherwise is either ignorant or misinformedor is peddling lies because phony panics over food safety improve television ratings.

Ozs views on GMOs and many other subjects have nothing to do with science. Dont take my word for it. Read the investigative report by Julia Belluz, published by Vox earlier this year: His departures from evidence-based medicine have gotten more extreme as hes become more famous, she wrote.

Michael Specter of the New Yorker has suggested that Oz is doing more harm than good. Last year, Democratic senator Claire McCaskill of Missouri scolded Oz for melding medical advice, news, and entertainment in a way that harms consumers.

The good news is that Oz appears to have modified his message, at least a little bit. In last weeks segment, he retreated from earlier claims that GMOs pose direct threats to public health: This debate is not about the safety of GMOs, he said.

This is an important concession. Oz knows that his critics have proven him wrong on the science.

He did not, bien sûr, admit his past errors. That would have required him to issue a humiliating apology that calls into question his knowledge and judgment.

And in a fundamental way, Oz conceded nothing at all. He insisted that farmers who grow GMO crops use herbicides that have the potential to change your hormones. This is just another wild accusation that he cannot provea scare tactic that abandons truth to boost viewership.

Moreover, Oz has thrown his support behind the top political goal of the special-interest groups behind the anti-GMO movement. They talk about transparency and the right to know whats in food, and want the government to mandate warning labels on packages of food that may contain GMO ingredients.

Their soundbites may sound compelling, but theyre also misleading. Whats the point of warning labels that caution against GMOs when, in the words of Dr. Oz himself, this debate is not about the safety of GMOs?

This raises a question: Has Dr. Oz ever visited with a farmer about why they choose to use this technology? Id be happy to host him on my farm in Iowa and talk about the benefits and safety of GMOs.

These labels may sound harmless, but they would require so many changes up and down the food chain that compliance costs would raise the price of food by as much as $400 ou $500 per year for a typical family, according to several studies.

People who want to avoid GMO ingredients already enjoy good options. They can look for the voluntary labels that many products now carry. They can also purchase food labeled as organic, which by law cannot include GMOs.

So heres what Oz wants: Labels that convey worthless data about safe products at great expense, at a time when consumers possess excellent information and alternatives.

Americans would benefit from the enactment of the Safe and Accurate Food Labeling Act, passed by a bipartisan majority in the House earlier this year and coming before the Senate. It strikes the right balance, letting food companies label the GMO contents of their products voluntarily but forcing none of them to make costly disclosures of unnecessary information that most consumers dont want.

What needs a warning label is The Dr. Oz Show: Watch it at your own risk.

Bill Horan cultive du maïs, soybeans and other grains with his brother on a family farm based in North Central Iowa. Bill volunteers as a board member and serves as Chairman for Truth About Trade & La technologie / Réseau mondial Fermier (www.truthabouttrade.org).

Follow us: @TruthAboutTrade et @World_Farmers onTwitter| Truth About Trade & Technology onFacebook.