Author: Jeremy Cherfas

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Active ingredients: who needs ’em?

A comment from Karl of Inoculated Mind, on the great Organic Tomato Debate, gives me an opportunity to sound off again on something I feel quite strongly about. That’s because, although a superficial reading of his comments and mine might suggest we disagree, at base, we don’t. Karl’s bottom line reads:

Bottom line: just eat your veggies!

And with that I totally and wholeheartedly agree.

At issue is the nutritional value of organic versus conventional tomatoes and, by extension, other veggies. The thing is, that comes after a discussion in which I say that more than flavonoids is likely to differ between organic and conventional. Karl points out that some compounds that plants produce in response to attack might be harmful, rather than beneficial, to humans. I moan on about the importance of dose.

Karl comes back with a link to a study of a genetically modified carrot that shows that “if you eat a serving of the modified carrot, you’d absorb 41 percent more calcium than from a regular carrot.” But the same report says that the daily requirement for calcium is 1000 milligrams, and that a 100 gram serving of the modified carrots offers only 60 milligrams, of which only about 24 milligrams is actually absorbed.

In other words, you could not possibly eat enough of the carrots to get your calcium without suffering beta-carotene poisoning, which just goes to reinforce my point about dose being important. ((I am certain I remember the case of a bloke in England who actually killed himself with excess carrot juice, but I cannot find it on the tubes: too much botulism and other nonsense clouding the results.))

The bigger point is that there is an obsession with active ingredients. Increasing the amount of this, that or the other is held to produce this, that or the other beneficial effect. And yes, maybe it does. And maybe it doesn’t, and maybe you can go too far. But people don’t eat active ingredients, unless they are rather far gone already. They eat food, and meals. And the interactions among foods and within meals mean that as far as the details of nutrition, especially micronutrition, go, all bets are off.

A far, far simpler way to boost nutrition and health is simply to eat different things, and lots of them, and forget about active ingredients, and high-lutein tomatoes, and super-calcium carrots, and golden rice, and flax oil, and all the other things that are touted because they contain more of some good thing.

Just eat your veggies. And your meat and fish. And your dairy. And your fruits and nuts. And everything else. Dietary diversity is the answer. ((And lest I am accused of ignoring poor people who cannot afford to buy anything, let alone organic tomatoes, it is probably more important to them than to the rest of the world that they maintain and expand the diversity of things they eat. But that’s another story for another time.))

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Why organic tomatoes are good for you

I’ve been meaning to blog this for almost a month. R. Ford Denison (a name to reckon with) blogged about some of his own research that summarizes 10 years of research into the flavonoid content of tomatoes grown conventionally and organically. Bottom line is that the organic tomatoes contained almost double the flavonoids of conventionals. I’m not going to go into whether that’s a good thing or not. Instead, I’ll stress the point that Denison himself makes, about Darwinian agriculture.

Why do the organic tomatoes contain more flavonoids? Maybe because flavonoids play a part in combatting herbivory. And they are often produced in response to pest attacks, rather than all the time. So one reason that organic tomatoes contain more of these compounds — which are believed to be good for human health — is precisely because on an organic farm there are a few pests that attack the plants. No pests, no need for defense, no benefits for human health.

This is just one aspect of what Denison calls Darwinian agriculture, a fascinating approach to the whole question of just what is being selected. There is, as someone else wrote, grandeur in this view of life …

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Stalking the wild peanut

A propos of the peanut’s past, it just so happens that one of the great peanut people of the world (as immortalized in this specific epithet) now lives just down the corridor at work. So I showed him that article. He was well pleased to see it, explaining for me how it confirmed previous ideas based on crossing and geography. Then, on the way out, he casually mentioned that seeds of one of the ancestors had been collected only once, and that it had never been found again.

“It’s probably extinct,” he said.

Ipaensis Well, that certainly adds a certain spice to an otherwise moderately routine story, I thought. So at the first opportunity I asked Luigi, who understands these things, to gbif A. ipaensis for me. ((Webbies are well aware of the verb “to google.” To GBIF is not yet a verb, as far as I can discover. Probably not in the present tense, and definitely not in the past. I hereby lay claim to it.)) Quick as a flash, he sent me arachis.kml, a KML file for Google Earth. There were precisely two entries, one for the type specimen at the Missouri Botanic Gardens and one for an accession in the USDA genebank. To me, they looked suspiciously located, on exactly the same latitude but about 45.5 km apart. And while the USDA’s specimen was reasonably near to a stream, Missouri’s was nowhere near water that I could see.

Arachis Ipaensis Luigi quickly confirmed that the Mo specimen, collected in 1971 and thus well pre-GPS, was probably in the wrong place; OK. These things happen. Then he was on the IM again, telling me that I could look at an image of the type specimen (that’s it over there) and that the USDA specimen was “unavailable”.

“What’s that mean?”

“Could be dead. Could be regenerating and they don’t have stock.”

“Bummer.”

“Yeah.”

And then we went about our independent business for a while until he sent “Can you imagine how hard that would have been 10 years ago? Or even 5?”

And it’s true. A few quick clicks, some very spiffy intertube tools, and we had the kind of information that could have taken months to gather back in the day. Information is going to be the life and death of efforts to conserve and make use of agrobiodiversity. And easy though it was to find out a bit about A. ipaensis, we don’t really know anything about the plant itself. Is it drought tolerant? Disease susceptible? Fertile with A. hypogaea? Got good genes?

And, in other Arachis news:

That’ll do, for now.