( TIME.com ) -- At every election , California 's ballot is filled with initiatives , but none received more attention this year than Proposition 37 . After the polls closed , Prop 37 -- also known as the `` Right To Know '' initiative to require labeling of foods that have been genetically modified -- failed to pass . If approved , California would have been the first state to require such labeling for foods sold in the state , and would have prohibited products containing genetically modified ingredients to be labeled or marketed as `` natural . '' Although the issue was ostensibly about food , the debate over Prop 37 quickly became political in recent months , with grassroots-based food purists supporting the measure and a well-funded agriculture and industry opposition campaigning against its passage . As the San Francisco Chronicle reports , Prop . 37 opponents , largely from industry and agriculture , raised over $ 45 million while the Vote Yes campaign , which was largely backed by consumer groups and the organic industry , raised about $ 6.7 million . TIME.com : Prop . 37 : Why California 's ballot initiative on GM food is about politics more than science . `` We 've said from the beginning of this campaign that the more voters learned about Prop 37 , the less they 'd like it . We did n't think they 'd like the lawsuits , more bureaucracy , higher costs and loopholes and exemptions . It looks like they do n't , '' the No on Prop . 37 spokeswoman Kathy Fairbanks told the Associated Press . Prop 37 supporters argued that citizens have the right to know what 's in their food and make educated decisions on what to feed their families , especially since long-term health effects are hazy . They wanted to see labeling , according to the ballot initiative , either on the front or back of packages `` if the food is made from plants or animals with genetic material changed in specified ways . '' Opponents from the biotech industry and Big Ag companies like Monsanto called the labeling deceptive and argued it would stigmatize foods that scientific evidence shows is not harmful . They also estimated that the cost of the labeling requirement would trickle down to California households , forcing families to pay $ 400 more in grocery bills each year . As TIME 's EcoCentric noted , however , that figure , which became a highly debated part of the campaign , assumes manufacturers would be replacing currently unlabeled genetically modified ( GM ) products rather than slapping new labels on them . TIME.com : Making sense of food labels . In the end , however , public health experts hope that it was the science that helped voters to make their decision . So far , there is little evidence suggesting that GM foods pose any harms to people that would warrant a label informing them of the modification . Major medical groups like the World Health Organization and the American Medical Association , in addition to the American Association for the Advancement of Science note that people have been eating genetically modified foods ( about 85 % of corn sold in the U.S. are man-made hybrids ) for nearly 20 years with no serious adverse effects . So what is the push for labeling really about ? In California in particular , it may be about a new-found appreciation for issues that many of us take for granted , including sustainable farming and animal rights . Opinion : Kids take up fight for 'real food ' In the New York Times Sunday Magazine , writer Michael Pollan says the movement has `` revitalized local farming and urban communities and at the same time raised the bar on the food industry , which now must pay attention ( or at least lip service ) to things like sustainable farming and the humane treatment of animals . '' He also admits the movement still has hurdles before it can establish itself as a campaign that will appeal to enough people to pass as a ballot initiative . But despite the defeat , the Prop 37 supporters see the campaign as a victory of sorts . `` Prop 37 is a really important and historic opportunity for an emerging food movement . It will fundamentally change the conversation about food and agriculture here in the U.S. , '' says Dave Murphy , founder of Food Democracy Now . `` It will also change how food companies have to respond to the millions and millions of Americans across the country who want to know what they 're eating . '' TIME.com : Vital farms : Raising the ultra-organic egg . Murphy says the campaign has highlighted Americans ' increasing distrust of the food industry and the lack of transparency surrounding what goes into the food they eat . Given that 50 countries already label GM foods in Europe , Australia , Japan , Russia and China , he hopes American skepticism will continue to hold food manufacturers accountable . `` We have a massive social movement for change to achieve labeling of genetically engineered foods in the United States . We understand that [ this ] loss ... that 's politics . The largest , most powerful corporations have spent millions of dollars to deceive the California voters , '' he says . More states will consider labeling laws in coming years , and Washington state and Oregon will likely have ballot propositions in the next two years . `` We will go to Washington and demand labeling from the next administration . We are not going away . We are just getting started , '' says Murphy . This story was initially published on TIME.com . California fails to pass GM foods labeling initiative .
The debate over Proposition 37 became political in recent months . Supporters argue citizens have the right to know what 's in their food . Opponents say it would stigmatize foods evidence shows are not harmful .