LULU GARCIA-NAVARRO, HOST:
At the Melbourne Zoo, the monkeys are no longer allowed to eat bananas. And the pandas are getting pellets instead of plums. In fact, fruit has been phased out completely. That's because the fruit that humans have selectively bred over the years has become so full of sugar the zoo's fruitarian animals were becoming obese and losing teeth. So how did fruit get so sugary? And what does that mean for us humans? We're putting those questions to food writer and author Frederick Kaufman, who joins us now. Welcome to the program.
FREDERICK KAUFMAN: Oh. Hi. How are you?
GARCIA-NAVARRO: I'm great. Thanks. So how has fruit changed since humans intervened in this process?
KAUFMAN: Well, listen. Since about 10,000 years ago in the origin of agriculture, human beings have been messing around with the sex life of plants. What you're looking at is natural varieties, which are puny, which are tasteless, which have no smell. And the farmers were like, we can do better than this. And they started crossbreeding almost from the get-go.
GARCIA-NAVARRO: I didn't think this was going to go so immediately to the sex life of plants. But, apparently, that's where we're headed. I mean, why, though, has modern fruit become as sugary as it has?
KAUFMAN: Well, one of the main dates to remember here is 1930, which is when the United States passes the Plant Patent Act. And from that point forward, the idea is we're trying to encourage farmers to actually manipulate those plants and to make them sweeter and to make them fatter and also to make them seedless, to take their sex away. In fact, what's happening is that when you actually take the sex drive of a plant away, when you take away its seeds, it actually puts more energy into getting fat and sweet.
GARCIA-NAVARRO: When you read about how fruit has impacted these zoo animals, were you surprised?
KAUFMAN: No, not at all. I mean, as I say, for years now, we've been lobbying these natural varieties of almost everything about them except their sweetness. You look at a watermelon. There is no seedless watermelon that's full of just bright red, luscious fruit. There's nothing like that found in nature. The tomatoes you find in nature are tiny and tasteless. The apples you find in nature are - almost all of them are spitters. People don't realize that everything that we're seeing in the supermarket, they're like superstars. They're like supermodels and elite athletes like LeBron James. That's what we're looking - at the supermarket.
GARCIA-NAVARRO: So let me ask you because eating the supermodel of the fruit world doesn't sound like necessarily a bad thing. You've written a book about this kind of stuff, "Bet The Farm: How Food Stopped Being Food." Is food part of the problem? Has it become less nutritious? Is it just good-looking and less good for us?
KAUFMAN: I think that the argument among the dietitians is that, yes, the higher sugar content is robbing food of a lot of its nutritional value. And I also think there is a tradition in America of somehow seeking perfection through our food, that somehow, if we eat right, we will make ourselves mentally and spiritually better. And so, of course, if we see row after row of perfectly glistening, absolutely gorgeous, completely look-alike apples, we think, yeah. I want that.
GARCIA-NAVARRO: But fruit is still good for humans?
KAUFMAN: Of course, eat like your grandmother told you to eat - is probably the best advice.
GARCIA-NAVARRO: Frederick Kaufman is a food journalist and author. Thank you very much.
KAUFMAN: Thank you.
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