NBCNews.com - Monkeys have been banned from eating bananas at a British zoo because those grown for people are too sweet and sugary for them.
"Giving this fruit to animals is equivalent to giving them cake and chocolate," said Dr. Amy Plowman, the head of conservation and advocacy at Paignton Zoo in southwest England. "People usually try to improve their diet by eating more fruit, but fruit cultivated for humans is much higher in sugar and much lower in protein and fiber than most wild fruit because we like our fruit to be so sweet and juicy."
This high sugar content is bad for the primates' teeth and can lead to conditions like diabetes as well as gastrointestinal problems as their stomachs are mostly adapted to eating fibrous foods with very low digestibility, she said.
The zoo began to wean the simian population off the sugary treats last year, gradually reducing the amounts so they could get accustomed to their new diet that now features lots of vegetables.
However, animals do still get banana if they are unwell and the keepers need to make sure they take medication.
"Putting it in a piece of banana works really well, as it's such a treat now," Dr. Plowman added.
Changing the diet has also resulted in behavioral improvements.
"Smaller monkeys such as tamarins and marmosets are highly strung animals and live in tight-knit social groups which can be quite aggressive at times," senior head Keeper of mammals Matthew Webb said. "Reducing the sugar in their diets has calmed them down and made their groups more settled."