Attorneys for the junk food industry have suggested that the tests were unfair and a distortion of the true nutritional value they provide to humans and cockroaches alike. Not really, but it wouldn’t surprise anyone if they did. LiveScience:

To find out, Moore and her colleagues picked young female cockroach nymphs and divided them into two dietary groups. Half were fed a good-quality balanced diet of protein-rich fish food and high-carbohydrate oatmeal, while the rest were raised on fish food only.

Both groups were allowed to eat as much as they wanted. The difference in diets “was not quantity but variety,” Moore said.

After the last molt, when the nymphs became adults, the team switched the diets of some animals. Half of the cockroaches raised with good quality diet lost their oatmeal, while half of the bugs fed poorly were promoted to a good-quality diet.

Eighteen days after the switch, the diet control ended and some of the surviving cockroaches were dissected. The rest were allowed to live on and reproduce.

The results: While the lifespan of the members of both groups was about the same, the cockroaches on the poor diet were fatter and took longer to mature.

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