House Republicans are pushing back against a series of public health measures, including school lunch standards and tobacco regulation, teeing up a confrontation with Senate Democrats and the White House over the reach of government in daily life.

The Republicans have used an agriculture appropriations bill to send several messages: They don’t want the government to require school meals that are more nutritional but also more expensive, they don’t want the government to prod food companies to restrain marketing to children, and they don’t want the Food and Drug Administration to regulate any substance based on anything but “hard science.”

They took aim at measures that are part of the Obama administration’s efforts to combat obesity among children and adults as well as some initiatives enacted by the previous Congress.

On Tuesday, the GOP majority on the House Appropriations Committee approved a 2012 spending plan that directs the Agriculture Department to ditch the first new nutritional standards in 15 years proposed for school breakfasts and lunches. The lawmakers say meals containing more fruits and vegetables, whole grains and low-fat dairy will cost an additional $7 billion over five years — money they say the country can ill afford in difficult economic times.

The committee also directed the USDA to scale back participation in an effort to develop voluntary guidelines for companies that market food to children. And it directed the FDA to exempt grocery and convenience stores and other businesses from regulations set to take effect next year requiring that calorie information be displayed.

“Our hope is that the Senate will reiterate their strong support for these policies rather than try to roll back important progress on obesity prevention,” said Margo Wootan, direction of nutrition policy at the Center for Science in the Public Interest.

The most intense reaction was generated by a provision offered by Rep. Denny Rehberg (R-Mont.) that would block the FDA from issuing rules or guidance unless its decisions are based on “hard science” rather than “cost and consumer behavior.” The amendment would prevent the FDA from restricting a substance unless it caused greater harm to health than a product not containing the substance.

“The FDA is starting to use soft sciences in some considerations in the promulgation of its rules,” said Rehberg, who defined “hard science”, as “perceived as being more scientific, rigorous and accurate” than behavioral and social sciences.

“I hate to try and define the difference between a psychiatrist and a psychologist, between a sociologist and a geologist, but there is clearly a difference,” he told the committee.

Rehberg said his rider was not targeted at tobacco, but anti-smoking advocates said Wednesday that the rider would make it impossible for the FDA to regulate menthol in cigarettes, a major decision pending at the agency.

“This would undermine a law that Congress passed with overwhelmingly bipartisan support two years ago,” said Matthew L. Myers, president of the Campaign for Tobacco-Free Kids. “It would undo the one thing that all members of Congress agreed upon, which was to protect kids from tobacco.”

A scientific advisory panel to the FDA found that menthol makes it easier for young smokers to take up the habit and harder for addicted smokers to quit. But the expert panel, which said a menthol ban would benefit the public health, said the mint-flavored products do not pose greater individual risk to smokers than standard cigarettes in terms of lung cancer, stroke and other diseases.

The Rehberg amendment would also prevent the FDA from restricting the widespread use of antibiotics in feed for farm animals, which many public health experts believe has led to the development of antibiotic-resistant bacteria that threaten human health.

About 80 percent of the antibiotics used in the United States are fed to farm animals, to help speed their growth and protect against illness in crowded farm conditions.

Groups including the American Medical Association and the Infectious Diseases Society of America have called on the FDA to ban the feeding of antibiotics to healthy animals. Scientists say that overuse of antibiotics in humans is a significant source of the problem but that there is growing circumstantial and genetic evidence that antibiotics given to animals are compounding the threat.

Agricultural interests oppose those limits, saying there is no scientific proof that farm animals are the problem.

“We have had discussions on the antibiotics used for livestock and pork and how they’re not using sound science on that, and I’m glad the gentleman has offered this amendment and I support it,” Rep. Jack Kingston (R-Ga.) said.

The lone Democrat on the committee who voted in favor of the amendment, Rep. Sanford D. Bishop Jr. (Ga.), said he represents cattle, pork and poultry farmers who are worried about the regulation of antibiotics.

“To the extent you can protect producers from unnecessary regulation, obviously with the economy and job situation being what it is we would like to have the most bang for the buck in terms of the producers,” he said.

Rep. Henry A. Waxman (D-Calif.), one of the sponsors of the 2009 law that gave the FDA authority to regulate tobacco, pledged Wednesday to try to defeat the Rehberg rider when the appropriations bill goes to the full House for a vote.

“This amendment ties FDA’s hands and will prevent the agency from taking basic steps to protect us from highly lethal threats, like tainted foods and drugs,” Waxman said in a statement. “Simply put, it will endanger American lives.”