Actresses Gwyneth Paltrow and her mother, Blythe Danner, took to Capitol Hill today to campaign against a bill that would prevent states from passing individual GMO-labeling laws.

Paltrow, who also runs lifestyle blog GOOP and has written cookbooks, said she was adding her voice to the bill’s opposition because she is a concerned mother, not an expert.

“My kids are normal American children and they eat everything everybody else eats,” she said in a speech in the Capitol building today along with Democratic Sens. Barbara Boxer of California,Richard Blumenthal of Connecticut and Jon Tester of Montana,

“I'm a home cook and I'm a cookbook author, and I'm a proponent of organic food and healthy food when I can, but we all eat genetically modified food. It's in the food supply.”

Paltrow, 42, acknowledged there are still open questions about how harmful to humans genetically modified organisms in food are, but that all consumers have a right to be able to know whether the products they buy contain them.

“Much the way I want to know if my food is farm-raised, or wild, or if my orange juice is fresh or from concentrate. I also believe I have the right, and we as Americans all have the right to know what's in our food,” she said.

The bill in question, the Safe and Accurate Food Labeling Act, or the “DARK Act,” as it’s called by opponents, would prevent states from mandating GMO labels, which proponents say would result in a patchwork of state-by-state regulations that could add costs to consumers.

It passed the House of Representatives in late July.

Paltrow was representing the “Just Label It!” campaign, a coalition of organic food companies seeking to defeat the bill in the Senate. She said a petition the group wrote had garnered 200,000 signatures in six days, and that they aim to have half a million by the time the congressional recess is over at the end of August.

“We would just love this information,” she said. “We think it's important as consumers and as mothers.”