Stand-up comedians have long joked that some things, like the actual components of chicken nuggets, are better left mysterious.
Recently, Mississippi researchers found out why: two nuggets they examined consisted of 50 percent or less chicken muscle tissue, the breast or thigh meat that comes to mind when a customer thinks of "chicken."
The nuggets came from two national fast food chains in Jackson. The three researchers selected one nugget from each box, preserved, dissected and stained the nuggets, then looked at them under a microscope.
The first nugget was about half muscle, with the rest a mix of fat, blood vessels and nerves. Close inspection revealed cells that line the skin and internal organs of the bird, the authors wrote in the American Journal of Medicine.
The second nugget was only 40 percent muscle, and the remainder was fat, cartilage and pieces of bone.
"We all know white chicken meat to be one of the best sources of lean protein available and encourage our patients to eat it," lead author Dr. Richard D. deShazo of the University of Mississippi Medical Center in Jackson, said.
"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," deShazo told Reuters Health.
"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."
The nuggets he examined would be OK to eat occasionally, but he worries that since they are cheap, convenient and taste good, kids eat them often. His own grandchildren "beg" for chicken nuggets all the time, and he compromises by making them at home by pan-frying chicken breasts with a small amount of oil, deShazo said.
"Chicken nuggets are an excellent source of protein, especially for kids who might be picky eaters," said Ashley Peterson, vice president of scientific and regulatory affairs for the National Chicken Council (NCC), a non-profit trade group representing the U.S. chicken industry.
According to the NCC, its member producers and processors account for about 95 percent of the chicken produced in the U.S.
"This study evaluates only two chicken nugget samples out of the billions of chicken nuggets that are made every year," Peterson said. A sample size of two nuggets is simply too small to generalize to an entire category of food, she said.
Two nuggets is a small sample size, deShazo acknowledged, and some chains have begun to use primarily white meat in their nuggets - just not the particular restaurants he visited.
"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," Peterson said.
"And every package of chicken nuggets in the grocery store by law contains an ingredient list and a complete nutritional profile, including fat content," she added.
The brief chicken nugget exploration was not meant to be an exposé of the chicken industry or fast food generally, but to remind consumers that "not everything that tastes good is good for you," deShazo said.
He and his colleagues chose not to reveal which chain restaurants they visited.
Consumers aren't necessarily being misled, since much of the nutritional information they need is readily available, he said.
"We just don't take the time to understand basic nutritional facts."