Breeding the Nutrition Out of Our Food | Hacker News Reader

Breeding the Nutrition Out of Our Food

nytimes.com

58 pointsakamaka20 comments

The science behind this article (hat tip to DanBC for his top-level comment linking to the author's promotional website) is dubious at best. Much of what can be called in general "phytochemicals" (chemicals found in plants) and that the author specifically praises as "phytonutrients" (chemicals found in plants with nutritional benefits for human eaters) can be, depending on DOSAGE, "phytotoxins" (poisonous chemicals found in plants). The poison is in the dose. Agriculture was pioneered by human cultures all over the world,

http://www.jstor.org/userimages/ContentEditor/1320774798622/...

because people wanted a reliable supply of food later. In many different regions, human beings noticed that planting seeds not only made a crop for the future likely, but also allowed artificial selection of high yield (a crucial concern at first) and better taste. Plant foods from all over the world have been actively selected for centuries or even millennia. In quite a few cases, human beings selected plants so that they were loss toxic and more bearable to eat in larger doses. The author is writing from ignorance of an evolutionary perspective informed by the general biological fact that most plants produce chemicals to REDUCE being eaten by animals, not to be beneficial to human beings in a wild state.

Even the plants that do want to be eaten (fruits) often produce agents intended to make you pass them violently in a distant location, which is why overconsumption of wild plants on hikes can result in gastrointestinal discomfort.

Just because plants produce toxins doesn't mean humans don't benefit from them. Humans and plants coevolved over millions of years, and it's not unreasonable for the human body to "expect" certain chemical triggers in the environment, and to go awry without them. It could be that plant toxins turn on specific cellular repair machinery which the body needs. This theory of hormesis is young but promising, and attempts to explain the health promoting effects of vigorous exercise, modest stress, resveratrol/sirtuin activation, and mTOR activation.

For example, restricting calories improves life span, but in high doses (zero calories) is fatal. But just because this strategy is bad at the limit doesn't mean it's bad in small does. Similarly, exposure to the sun results in skin cancer in large doses, but produces cancer fighting vitamin D in small doses.

What is the correct dose of plant toxins? We don't know, but it could well be higher than in bred plants, at least for adults. Children generally hate bitter foods and the reason could well be to protect their small livers from overdose.

...restricting calories improves life span...

I suspect that your knowledge on this topic has hit its expiry date.

You are probably thinking of the various studies relating to rats and mice. However the correlation failed when we went to monkeys, and there is no reason to believe that it works in humans. See http://www.nature.com/news/calorie-restriction-falters-in-th... for verification of that.

One primate study verified the effect and one did not; see http://www.davidstipp.com/on-calorie-restriction-monkeys-mag... for an interesting, if biased, analysis of the NIH study.

Thank you for the additional information. I've updated my mental note from "disproven for primates" to "unclear".

The author of this article, Robinson, repeatedly claims that indigenous americans were incapable of and ignorant towards selective breeding. This is false.

He proposes that teosinte spontaneously mutated into maize, which is totally contrary to the accepted history, I've never even heard anyone make this claim.

Samples of maize in its modern form have been found directly dated back 6000 years, and inferentially dated back 9000 years, to the advent of agriculture in the western hemisphere.

Matsuoka showed through molecular dating that maize was likely domesticated from a single source in a single event around 9000 years ago.

Matsuoka Y, Vigouroux Y, Goodman MM, Sanchez J, Buckler ES, Doebley JF. 2002. A single domestication for maize shown by multilocus microsatellite genotyping. Proc Natl Acad Sci USA 99: 6080-4.

Robinson's claims here that north american indigenous peoples didn't breed for traits and this was a new thing that only the english did is totally absurd. Various groups developed their own varieties that were attuned to their particular land and territory. Tribes as far north as Manitoba grew vast tracts of land in maize varieties they developed that were frost tolerant!

Boyd recently did an analysis of microfossils from ancient northern pottery to identify ancient maize farming regions and found that nearly every site tested had maize, including multiple sites that were north of the subarctic zone.

http://anthropology.lakeheadu.ca/personal/mboyd/uploads/Boyd...

There wasn't much discussion of pre-Columbian plant breeding in this article. Do you have any links to where the author makes these claims?

This opinion piece is by someone who campaigns on this issue. The website has lots of citations to research. I haven't checked those, so I don't know if the journals are reputable or if the research is hooey or not.

(http://www.eatwild.com/jo.html)

The citations on that site look legit. It's not exactly my field, but the titles and the journal names both scan like mainstream science, i.e. technical and restrained.

However, those references are all about methods of raising animals. This article is on quite a different topic, nutrient content in plants. I'm wary of the way a host of mostly unspecified compounds are lumped together as 'phytonutrients' and presented as universally beneficial. I've never heard that term before, and it's got the same kind of ring as 'detox'. There's plenty of chemicals in plants that really aren't good for us - see for example this review of legumes: http://tinyurl.com/pydm56o (email me if you're interested but don't have access).

It roughly fits into the ideas of the 'paleolithic diet', that what people ate ~20k years ago is nutritionally optimal. That's controversial, and it looks like Wikipedia has quite a detailed entry on it.

"It is now known that many of the most beneficial phytonutrients have a bitter, sour or astringent taste"

Well, thanks evolution...

"A blast of radiation had turned the corn into a sugar factory!"

What a great story, making GMOs before anyone else.

> Studies published within the past 15 years show that much of our produce is relatively low in phytonutrients, which are the compounds with the potential to reduce the risk of four of our modern scourges

While this sounds really informative, it is a very vague statement. "If we eat different food than we currently do we may not have to deal with these things".

Lack of nutrients are not killing us, too much of some sort of X is. (I think it's sugar and high refined carbs, some think it's fat, some believe both)

The reason vitamin pills are consider phooey is because there is no evidence of missing nutrients in our diets (There are some exceptions, ie when pregnant, if you're vegan etc)

End of the day, anything that makes us eat less X is what we need. To me that's fruit and veg that taste great and are cheap, not their nutrient content.

And no single word about animal sources

The thesis of the article was to contrast our wide-spread belief in the health benefits of fruits and vegetables with the actual (significant) lower health benefits measured by some (significant) measure. It does not compare health benefits of fruits and vegetables with meat.

Having said that, however, just as we have bred plants to our subjective preferrable tastes, wishes, and ideas, we also have bred livestock for specific treats, like docility and size, without any regard for health value for humans.

The standard hog has been leaned up considerably, based on the idea that less fat is healthier (also because lard is less valued, but still).

Edit: And consumers can choose healthier animal sources without triggering any breading, replacing beef with chicken is widely considered a healthy thing, fish even more than chicken.

Sure, we now care about that. But we've been breeding animals for over ten thousand years. During that process, what did we lose? What of that can we get back with scientific supported breeding?

Or to state it differently, was the prehistoric cow significantly healthier for us than our current cow (or chicken)? And will it be possible to breed that extra "healthiness" back in?

As a biologist, my intuition is that there's been little change in the nutrient value of meat. Plants synthesise a very broad array of compounds which affect their flavour and nutrient value. Animal biochemistry is nowhere near as complicated, so there's not so much that can change.

There may well have been a shift in the protein/fat ratio of meat, but I guess that would be dwarfed by changes in what we eat and how we prepare it.

Grain-bred animals totally lack omega-3, comparing to grass-fed.

And my intuition tells me that is only a small part.

She recommends herb burgers made with "grass-fed beef or poultry."

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