DES MOINES, Iowa — Debate about the health attributes and risks of raw milk is spilling into statehouses and courtrooms across the country as proponents of unpasteurized dairy products push to make them easier for consumers to buy.

Supporters of the raw milk cause say pasteurization, the process of heating milk to destroy bacteria and extend shelf life, destroys important nutrients and enzymes.

"We have new science today that shows raw milk contains ... enzymes that kill pathogens and strengthens the immune system," said Sally Fallon Morell, president of the Washington D.C.-based Weston A. Price Foundation, a nonprofit group pushing for increased access to raw milk.

Enzymes and other nutrients are "greatly reduced in pasteurized milk," she said.

Public health officials disagree, saying raw milk carries an increased risk for bacterial contamination that can lead to illness and even death.

More than 1,500 people became ill from drinking raw milk between 1993 and 2006, the most recent data available from the Centers for Disease Control and Prevention. Of those, 185 were hospitalized and two died.

The CDC said not all foodborne illnesses are reported, meaning the actual number is likely higher.

Fallon Morell said there also have been illnesses and deaths related to pasteurized products and that linking illnesses to raw milk is not an accurate assessment of the nutritional benefits of drinking unpasteurized milk.

The sale of raw milk is prohibited in 23 states, although seven of them let people get milk through so-called herdshare programs, in which customers can buy ownership in a cow in return for raw milk from the animal.

Retail sales of raw milk is allowed in nine states and 19 allow the sale of raw milk from a farm directly to an individual.

Lawmakers in seven states — Georgia, Iowa, Missouri, New Jersey, North Dakota, Wisconsin and Wyoming — have introduced measures this year seeking to change laws governing raw milk.