HOUSTON -- US farmers and advocates say genetically-modified food (GM food) is nothing but a boon to mankind, but  sceptical consumers are still pushing for labeling to make such products easier to avoid while shopping.

In Texas, where labeling foods as genetically altered is voluntary on the part of the producers, not much in the grocery stores is disclosed as GM. According to GM food producers, that's because labeling is unnecessary.

Texas farmer Russell Boening, who produces genetically modified corn and cotton seeds on his family-run ranch 60 km southeast of San Antonio, said he is concerned that the average American doesn't know enough about genetically modified organisms (GMOs) and thus would be unduly put off by marked packaging.

"I do have some concerns about labeling GM foods. I question whether the average consumer has or is willing to take the time to educate themselves about how different types of food are produced and whether they are safe," said 54-year-old Boening.

"It concerns me that some consumers, when they see the GM foods label, may not buy it because they don't understand it. Then they may not buy the non-GMO foods because it is more expensive, so now their family does not receive that particular food product at all."

Texas Panhandle rancher Billy Bob Brown said genetically modifying foods merely speeds up the process of finding and developing the best food producing crops, facts that can't be reduced to a 'one size fits all' label.

"It's just a new way of doing an old thing in agriculture," said Brown. "I see no reason to label. In fact, it (GM food) is becoming widespread in use, so it may be easier if labeling is necessary to label (non-GMO) foods.

At the Food and Agriculture Communications division of the Biotechnology Industry Organization -- the world's largest biotechnology trade association -- division director Karen Batra said genetic modification is just like traditional breeding.

"Crops and foods that have been genetically modified are no different than conventional -- or even organic -- crops and foods in terms of health and food safety," Batra said. "Billions of people around the world have been consuming GM foods for nearly two decades with no reported ill effects."

Every credible scientific authority in the world agrees that health and safety are not at issue, she said.

"The world's most prestigious scientific organizations have looked at hundreds of independent scientific studies on GM foods, concluding that foods with GM ingredients do not pose any more risk to people than any other foods," Batra said.

That list of research organizations includes the World Health Organization, the American Association for the Advancement of Science, the American Medical Association, the Chinese Academy of Sciences, the British Medical Association, the Council for Agricultural Science and Technology, the International Council for Science, and the European Food Safety Authority, just to name a few.

Batra said that despite the reservations of American consumers, GM food products have been served on US tables for decades.

"In the United States, approximately 90 percent of the corn, soybeans and sugarbeets are GM varieties," she said. "Other foods that have genetically modified varieties are papaya, squash, canola, alfalfa, tomato and sweet pepper. Approximately 70 percents of all processed foods contain some of these ingredients."

Despite the fact that they are likely to be ingesting genetically altered foods, US consumers say they are still wary of genetically engineered food products and want such foods to bear warning labels.

Houston school teacher Marianne Chase agrees with her doctor that GM food products, as opposed to organically grown food, are creating health issues for Americans.

"More people are becoming diabetic and have health problems. We are fat, overweight and we need Omega 3 that is in natural foods such as homegrown tomatoes," Chase said. "I think mass-produced vegetables are causing people to be sick. There are no labels on vegetables, whether or not they are treated with chemicals. Even meat and fish and everything we buy is not really good for you, and everybody is trying to get away from glutens and stuff that's proven to be bad for you. Half of the nation is diabetic and I think it's because of what we eat."

Chase said that an organic diet is too expensive, so she is growing her own spices and tomatoes." Because the vegetables in the store are sprayed with stuff and force-ripened, I don't know if they have very many nutrients at all," Chase said.

The Center for Food Safety's science policy analyst, Bill Freese, also casts a critical eye on GM food products, and believes that the system currently in place to ensure the safety of these products is flawed.

"We don't have a reasonable scientific regulatory system; we have a rubber-stamp system designed to get these foods onto the market as soon as possible rather than ensuring they are safe," Freese said. "Genetic engineering causes unintended results and (they) appear to be hazardous."

One effect of GM foods, he said, is the creation of new toxins in food that were never there before.

"Genetic engineering can elevate toxins already in the plant and also have unintended lowering of nutritional value of the food," Freese said.

Many believe one risk of genetic engineering is that it causes food allergies, ranging from mild to severe and life-threatening, by introducing entirely new protein into crops that is new to the human system.

Jeffery M. Smith, filmmaker and executive director of the Institute for Responsible Technology has authored books and magazine articles touting GM foods as unsafe for human consumption.

"Based on considerable scientific evidence, we now know that the current generation of genetically modified organisms is not safe and therefore should not be used in the food supply," Smith said.

"Thousands of US physicians now prescribe non-GMO diets to all their patients. Many describe significant, even dramatic improvements in health and alleviation of symptoms, such as gastrointestinal, immune, and reproductive issues."

He said the same types of problems also clear up in livestock or afflicted lab animals taken off GMO feed.

"We don't think it's a coincidence that these disorders are on the rise in the US population since GMOs were introduced in 1996," Smith said. "Based on my 17 years of study of this issue, including my two books and three movies, I choose a diet of non-GMO foods and recommend others to do the same."