In response to the study carried out by the university, the National Chicken Council released a statement.

Ashley Peterson, PhD, National Chicken Council vice president of scientific and regulatory affairs said: "In making chicken nuggets, our members use quality ingredients and adhere to all food safety laws and regulations to create a product with high quality their customers and consumers expect. Chicken nuggets are an excellent source of protein, especially for kids who might be picky eaters.

"This study evaluates only two chicken nugget samples out of the billions of chicken nuggets that are made every year. It is not scientifically justifiable to make inferences about an entire product category given a sample size of two.

"Chicken nuggets tend to have an elevated fat content because they are breaded and fried. But it’s no secret what is in a chicken nugget – most quick service restaurants have nutritional information posted in the store or on their Website. And every package of chicken nuggets in the grocery store by law contains an ingredient list and a complete nutritional profile, including fat content."

While all edible, the ingredients don't add up to a good choice, said Dr Richard deShazo, UMMC distinguished professor of medicine, pediatrics and immunology.

"I was floored," Dr deShazo said. "I had read what other reports have said is in them and I didn’t believe it. I was astonished actually seeing it under the microscope."

White chicken meat is one of the best sources of lean protein available, Dr deShazo said, and physicians often encourage their patients to eat it.

"What has happened is that some companies have chosen to use an artificial mixture of chicken parts rather than low-fat chicken white meat, batter it up and fry it, and still call it chicken. It is really a chicken by-product high in calories, salt, sugar and fat that is a very unhealthy choice. Even worse, it tastes great and kids love it and it is marketed to them," he said.

He chose to not name to two restaurant chains.

"This is about people having the knowledge and resources to make healthy choices," Dr deShazo said.

Chicken nuggets are fine when eaten occasionally within the scope of a healthy diet, he said.

"We’ve got to learn how to distribute our calories across a diet that includes lean protein, fresh fruit and green vegetables," Dr deShazo said. "We’re literally eating ourselves to death with obesity. We have to learn to eat a balanced diet where it’s not all carbohydrates and fat."

Noting the popularity of chicken nuggets with children, Dr deShazo, a vocal advocate for improving Mississippi’s health, said the experiment wasn’t designed as a comprehensive study of nuggets from all major fast-food chains. Nor do the results from two, randomly selected nuggets from two prominent chains represent all chicken nugget offerings available.

"My concern is that these constitute a large part of people’s diets. Particularly children," he said. "When you fry any food, you’ve got a problem because you add a lot of calories to it. And we eat high-fat foods like chicken nuggets rather than fresh fruits and vegetables."

If a large per centage of a particular food is fat, "And it is the predominant food that your child eats, they are going to become obese. And they could eventually get diabetes, high blood pressure, osteoarthritis and other diseases we call co-morbidities."

For the examination, Dr deShazo worked with Dr Steven Bigler, a pathologist at Baptist Health Systems in Jackson, who stained, fixed, sliced and analyzed the nugget sections.

In their paper, the physicians wrote that meat constituted about half of nugget No. 1.

"The nugget from the first restaurant was composed of approximately 50 per cent skeletal muscle, with the remainder composed primarily of fat, with some blood vessels and nerve present. Higher-power views showed generous quantities of epithelium and associated supportive tissue including squamous epithelium from skin or viscera," they wrote.

"The nugget from the second restaurant was composed of approximately 40 per cent skeletal muscle. Here, too, there were generous quantities of fat and other tissue, including connective tissue and bone spicules."

He said fast-food chains aren’t necessarily misleading consumers.

"We just don't take the time to understand basic nutritional facts - this is a health literacy issue - and to push back when our kids and grandkids, who do not know the risks of being obese, beg for unhealthy foods."

The American Journal of Medicine published Dr deShazo's findings online in September ahead of its print issue.