More research is needed to show that alternative therapies such as acupuncture and herbal supplements work, and this may mean changing laws that protect the industry, a committee of experts said on Wednesday.

Nearly a third of Americans use such therapies and it is increasingly important to standardize those treatments and show whether and how they work, the Institute of Medicine committee said.

It did not say who should be responsible, but urged Congress and federal regulators to work with industry, researchers, consumers and advocates to find a way to test alternative approaches.

“The main message is that complementary and alternative therapy use is widespread and here to stay,” Dr. David Eisenberg, an expert in complementary and integrative medical therapies at Harvard Medical School in Boston, said in a telephone interview.

“The same rules of evidence of effectiveness and safety should apply regardless of the origin of the therapy.”

The Institute of Medicine, an independent group that advises the federal government on health matters, was asked to identify barriers to better research on complementary and alternative therapies.

“Health professionals and patients should have sufficient information about safety and efficacy to take advantage of all useful therapies,” said committee chair Dr. Stuart Bondurant, executive dean of the Georgetown University School of Medicine in Washington.

“We believe that the same research principles and standards for showing effectiveness should apply to both conventional and complementary and alternative treatments,” he added in a statement.

“And because evidence is a key element of prudent decision-making, we need to change the current regulation of dietary supplements in this country to encourage more studies of these widely used products and to ensure their quality.”

The Dietary Supplement Health and Education Act, commonly known by the acronym DSHEA, says supplements can be regulated as foods rather than drugs. This lets supplement manufacturers off the hook for the safety and efficacy tests required of drugs.

“Given that manufacturers are not required to conduct testing and are unable to patent many supplements, there is little incentive for supplement makers to invest in research on the effectiveness of these products,” the Institute said in a statement.

The report includes a survey done at Harvard Medical School showing that 35 percent of Americans used complementary or alternative medicine in 2002, virtually unchanged from 1997.

It found a 50 percent increase in the use of herbal supplements, growing from 12 percent of adults in 1997 to 18.6 percent, or 38 million adults, in 2002.

More than 10 million adults, or 5 percent of the population, practice yoga, the survey found.

The survey was based on the National Health Interview Survey of 31,000 adults done by the National Center for Health Statistics.