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Nutrient deficiencies in rice grown under higher carbon dioxide (phys.org)
165 points by pizza 70 days ago | hide | past | web | favorite | 93 comments

This is the same study that the publishing scientist quit the USDA in protest over.


that is outrageous. it looks like the trump administration's paranoia about politics in science is taking a toll

We have to accept we at this point are unable to address reality. There is a side not acting in good faith, and it is at a time where pressure will rapidly ramp up from that very reality, what will be blamed will be witchcraft, the others and everything else. But addressing reality would destroy their identity.

I previously made the observation that global warming induced nutrient density loss correlates with the mammal obesity trend: https://news.ycombinator.com/item?id=18949373

Everyone here commenting about the great news about how yields have increased is totally wrong. Droughts, prolonged heat waves, and flooding will wipe out whatever small percentage in yields from higher atmospheric CO2 have/will result. Not to mention the health effects: people that are paradoxically at the same time obese and malnourished.

> people that are paradoxically at the same time obese and malnourished

I don't see the paradox? "Energy" and "nutrients" both are in food but they are not the same (okay, unless somebody wants to start arguing about word definitions in which case I refer them here: https://www.lesswrong.com/posts/7X2j8HAkWdmMoS8PE/disputing-... -- you guys know exactly what I mean). If your body wants (certain) nutrients but they are always accompanied by way too much energy that ends up being stored as fat than you end up hungry as well as fat. No paradox.

Also using "energy" and "nutrients" like I just did: https://edis.ifas.ufl.edu/fs176

Many discussions about obesity are accompanied by comments "they just need to eat less because calories in > calories out - it's just physics" ignore that energy is just one of many aspects of why we eat.

I think you & the parent probably agree; nutrition research has traditionally treated obesity and malnourishment as opposites as the combination has been rare in history but indeed there is not a contradiction.

"A calorie is a calorie" violates the second law of thermodynamics https://www.ncbi.nlm.nih.gov/pmc/articles/PMC506782/

That's really hilarious that the article title is completely in rejection to the conclusion. I don't see many articles that do the same in the medical field.

A paradox is just something which is "apparently" false or contradictory but in actuality true. The paradox is just that you would expect someone who's well-fed to the point of being obese to at least have enough nutrients to be healthy.

Here's an interesting article looking at net decreases in yield of most of the top 10 staple food crops in the world. It includes sorghum and wheat and more, and has a bit more discussion of geographic shifts, for instance. https://www.minnpost.com/environment/2019/07/climate-change-...

One solution is slow-growing plants - domesticated plants are bred for yield.

This is why I'm a proponent of genetically modified organisms in agriculture. The world needs to be fed and needs to be fed properly, and it is pure privilege to deny use of tools in our toolbox that abet solutions to global hunger. I won't deny the issues around the corporatization of farmland, vendor/seed lock-in and IP issues, and the litany of other issues around its use - but damn is it a viable solution for vitamin deficiency and a way forward through changing environments.

GMOs for human consumption are not necessary. Enormous amounts of plant biomass are grown to feed livestock.

GMOs also have an issue of exposing the once very inert system to black swan events, health or environmental issues.

Similar thing happened with pesticides. Before GMOs can be used we should at least test them rigorously for a couple of generations. But yeah, that stuff did not happen with pesticides, cars or anything else that now has huge externalities.

Plants are used to feed livestock for their energy, not their nutrients.

GMOs would be used here to limit the amount of energy derived (carbohydrate) with regards to nutrient density.

Also, for what it's worth, part of the plant biomass used to feed livestock is inedible by humans (think cellulose).

Yeah, but the reason GMOs started was to improve yields for livestock-feed related plants and is the reason GMOs exist today (if we ignore cotton, which is GMO-ed primarily for the clothing). I'm pretty sure soybean is nutrient dense livestock feed, not just a carbohydrate source.

The only reason GMOs would exist for humans would be to improve the yields of most popular plants which are obviously not raised for nutrition but for taste. Almost every other plant in the world is produced in such minuscule amounts compared to soybean, wheat, maize and rice that there's no need for GMO.

I would say that enough land is spent on livestock feed that if we switched to meatless diets we would likely be able to feed everyone. There are regions only suited to food for livestock but most of the world imports food making it not an issue. The regions that don’t import food that tend to eat more meat from necessity are also likely to be the places that don’t contribute to overuse of land for livestock food.

I used to work on GMOs and I fully believe that they are an important part of the solution to world hunger. But increasingly I feel that the same types of corporations/stockholders/countries that are directly/indirectly responsible for the dire state of the environment and all that will flow from it, are the same ones who will benefit from everyone being forced to use GMOs.

The answer is to end capitalism, so that the GMOs are no longer controlled by corporations that no longer exist.

The world does need GMOs, I just wish that all GMO's that are sold for human consumption were required to have their genome available under an open source license.

Side note to your main point: the IP issues around GMOs are little different than the IP issues around other types of agritech, so I don't think it's a huge concern.

Governments and non profits are free to make GMOs that are available to all without IP issues, too, as has been done with golden rice.

> Side note to your main point: the IP issues around GMOs are little different than the IP issues around other types of agritech, so I don't think it's a huge concern.

I'm no expert on the issue, but from what I'm aware this is not true.

At least in the EU it seems there's now largely a consensus that non-GMO plants can't be patented:


There are still other IP rights that can apply to plants, but patents are a very different beast.

This may differ based on jurisdiction; in the US plants (including fungi) are patentable.

From the US Patent Office:


As just one example, the University of Minnesota got $6M in payments for their patent on HoneyCrisp apples before the patent expired:


golden rice isn't free if you want to make money off of it (more than $10k it seems). And none has ever been grown for consumption it seems.

On the plus side of golden rice taking so long to amount to anything, any patents from back in 2000 when the non-commercial licensing thing dates from have almost certainly expired; it should be unencumbered by now.

I'm not finding anything like what you're talking about in my web searches, could you expand on that a bit with some sources?


underneath "The essence of the Sublicensing Agreement"

Great, thank you! Is this an attempt to decommodify food (in the Marxist sense)? Do non-corporate farmers typically make more than $10k/year in developing countries?

Beats me. I literally just googled golden rice 10,000, found what you were looking for, and dropped in a link.

I'm exasperated by the holdup on golden rice. I'd buy a sack of it and put it in the ground myself if it were on the market.

“Full speed ahead and damn the licensing issues!”

I think we should also understand the cause of this deficiency.

E.g. the increased CO2 may be causing the bulk of the plant to grow bigger while the overall production of nutrients remains stable (nitrogen-limited ?) resulting in a lower concentration.

Adapting fertilisers might improve this. Or not.

Indeed. Genetic modification is doing with a scalpel what we've been doing with a sledgehammer for thousands of years with selective breeding and hybridizing.

Yep. And both tools can be used carefully or carelessly.

Do you have an example of selective breeding that resulted in a negative outcome?

High fructose corn syrup, broiler chickens who can barely stand up, pugs who can barely breathe, crops prone to blight.

"The Windup Girl" by Paolo Bacigalupi has an interesting part of the plot involving GMO food and companies.

So we need open-source and probably government funded (UN-funded ?) vegetables.

> it is pure privilege to deny use of tools in our toolbox that abet solutions to global hunger

I'm curious if you support the solution of allowing human population to decrease by encouraging fewer children.

corporations are not incentivized to make GMOs that are more nutritious. experience shows that they are more likely to make GMOs to sell more pesticide

Maybe it's because the plants grow faster with the same fertilizer, and there's not much of value in the soil any more.

Or the plants grow faster and contain exactly the same "nutrients" "diluted" in more starch. (The scare quotes are there because large parts of the world need those so-called empty calories even more than the vitamins.) The article talks about concentrations, not total amounts, after all.

Past time for a tax on carbon.

An important thread that is related: https://twitter.com/SarahTaber_bww/status/101867427349651865...

Context starts here: https://twitter.com/davidorlo/status/1018616684603691013 (it's what the 1st tweet links to)

This has been downvoted, but it appears to be highly relevant. It is a tweet thread from a crop scientist (scroll down, there are many tweets, not just the one linked).

The gist is that in the co2 studies, fertilizer etc to plants are not increased. Analogous to keeping human food constant even if a body is growing faster.

She says this makes sense for the experiments: it lets us isolate effects of components on plants. But in real life farmers add more fertilizer if plants grow faster.

This appears to directly address the linked study and warrants consideration and a reply.

Yeah, I think it's an interesting read although I disagree with some of her remarks. She's right that in the past we just threw fertilizer at plants (more is better until you burn the ground), and she's right that increasingly US farmers for instance are practicing targeted fertilization and maybe can make up for some of this.

She doesn't seem to be taking into account the situations in the poorest parts of the world, where this is not being done -- and where rice is a far more important staple than in the US. She says, "Folks who are getting all their nutrients from plants generally eat at least some concentrated forms of plants, especially concentrated plant proteins: tempeh, seitan, nut milks & butters, etc." Um, I was literally talking on Thursday with a woman who was describing her childhood and the comfort she takes in a big warm bowl of rice, which was a majority of her meals growing up because she could cook it in the rice cooker without her parents' help while they were at work. My spouse also grew up eating big bowls of plain rice, although he did get to put soy sauce/ketchup/sriracha on top. They sure as (&^ were not eating seitan and tempeh on top. I can walk down to the Whole Foods 10 blocks away and buy some, uh, spirulina and salmon and whatever the cool kids are eating these days... chia? or is that passe? but that's not the situation for subsistence farmers or the vast swathes of people in cities living on the above-referenced bowls of imported rice. And these vast swathes of people often don't have great healthcare access, either, and so are more vulnerable to some of the cascading problems that result.

Last, I don't know how much she knows about nutrition. I'm glad she pays attention to iron content in the tweet series... but that's not the sum of micronutrients. The roles of vitamin D, chromium, biotin, and thiamine in development of type 2 diabetes are discussed here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3313629/ Micronutrient deficiency and obesity has been in the nutrition literature since at least 2009 at this point. I could link you to 10 more peer-reviewed articles but they're all behind a paywall :( Here at least is an editorial from 2010 with some review of articles recent at the time, and in particular some remarks about micronutrients and "clinically relevant weight loss" in Asians and perhaps others.

Anyhow, thanks for defending the tweet thread :) It was interesting!

A lot of nutritional deficiency doesn't "come" from the plant, rather, the processing/refining of the plant before consumption

Example https://medium.com/war-is-boring/eating-too-much-rice-almost...

Thank you, that first link explained it really well!

Also, I just found out you get about 8-9x the nutrients from cooked veg vs raw.

"Is Our Food Becoming Less Nutritious?: Veritasium"[1] is a good short video that puts this into context.

[1]: https://www.youtube.com/watch?v=Yl_K2Ata6XY

At what point does the rice just die from too much heat?

Enzymes involved in photosynthesis break down with heat starting at around 20 degrees Celsius, and by 40 degrees Celsius (104 Fahrenheit) break down almost completely. Plants can use their stores of carbohydrates when photosynthesis is not possible. Given a long enough heat wave, plants will use up their stores of sugar and die, even if they have enough water available. Even if they do not die outright, the yield of crops will be reduced to a fraction of what it should be (autophagy when they should be growing).

Rice is very water intensive, and droughts are likely going to be a much bigger problem for rice crops before prolonged heat waves become normal.


How can that be right? 20c is on the low end of room temperature. So a plant is actually bad at photosynthesising when it’s warm and there’s the most sunlight? Why? Wouldn’t this mean greenhouses are BAD for plants?


Is the closest thing to a real source I could find at short notice. I found this surprising as well, I guess it merits some more casual research!

> So a plant is actually bad at photosynthesising when it’s warm and there’s the most sunlight?

Yes. That is one of the big reasons why it is difficult to grow crops in desert regions even with irrigation.

> Why?

Thermal properties of chemical reactions. There is a very narrow range of temperatures at which the chemical reactions needed for plant life and growth can occur. The space of possible chemical reactions are limited by the availability and distributions of various elements and molecules in the environment that the plant has available, so there is not going to be a magic evolution or breeding of heat-tolerant crops that will violate these chemical constraints.

> Wouldn’t this mean greenhouses are BAD for plants?

Greenhouses are not "tropical desert hot houses." They are used to boost temperature in cold climates for the specific crops that are grown. Tomatoes like 25 degrees Celsius, but, for example, lettuce will not grow if it is above 21 degrees Celsius.

Yeah I agree. Vast parts of jungle land is consistently around 25-30C, surely the plants there are adapted for that?

And that 20C is in the shade, while foilage is typically exposed directly to the sun, at significantly higher temperatures.

Plants evaporate a lot of water, so their leaves are likely a bit cooler than ambient temperatures.

Yeah, I don't believe this at all. In Florida for instance the daily high never really goes below 20C all year, and the name literally means "flowery". 40C I might believe, but 20? No way.

Well, today it was easy to spot the daily anti-car and climate panic articles. This is not why I read HN...

Should be an easy fix, easily accomplished well before 2050

Simply purchase your single-generation seed from Monsanto at exploitative prices, and you can continue to subsist without major nutritional deficiencies.

Well, you could just never release it, making it basically illiquid. Venezuela and Zimbabwe of recent come to mind...

Risk of what? Just say it in the headline.

Vitamin B deficiencies, shortened lifespan and more issues in fetal development

Sorry, pared down the original title because of 80 char limit

The paper feels full of lies by omission to leave out the caloric yield increase and only discuss the vitamin density side. This is likely a case where vitamin production per acre are unchanged in a elevated CO2 enviroment, and calories per acre increase by 20%.

That's the point of much of this research. The elevated levels of CO2 enable the plants to grow faster, but absorbing the same nutrition, and then we absorb the same amount of calories, with a lower nutrition level, so we become malnourished.

The increased yield should lower the price. Poor people might then have enough surplus income to buy more nutritious foods. (And perhaps less rice - which may be what's called a "Giffen good".)

Not necessarily. For one, increased yield doesn't always result in lower prices, because the free market generally isn't that free (most of our agriculture is heavily subsidized by the government). Another problem is that access to nutritious food is extremely limited for poor people, for a variety of reasons. Overhead and supply chain economics influence whether local businesses can survive. Marketing/advertising and industry pressure on politics increases the likelihood that cheap, non-nutritious, shelf-stable foods will be more prevalent in stores. And then there's the general self-medicating-through-salt-sugar-and-fat cyclical effect, and overall lack of education on healthy eating and cooking. Even when you can find it and afford it, poor people have less free time to cook.

Rice is a food that is shelf-stable, cheap, and (when enriched) provides a bare minimum of nutrition. Reducing the already-bare-minimum nutritional level, or increasing the heavy metals already found in many varieties, will have a significant effect on already vulnerable populations.

For subsistence farmers, prices and markets are irrelevant. The effect of higher yield would be that less of their land needs to be devoted to growing rice, leaving some free land for growing other foods.

In anything approaching a free market, it is hard to imagine that lower production costs won't reduce the price of a heavily-traded commodity with millions of producers.

In a communist system of collective farms, or a fascist system of government-mandated prices with monopolistic distribution networks, it is anyone's guess what political decisions will be made. Such systems regularly produce politically-motivated famines, so slightly lower nutrient levels will be the least of their worries.

This perspective is invalid in large parts of the world. The most important macro nutrients are sugar and fat, the very thing americans (and only americans) call "empty calories". In most places, more calories is good. Meeting the requirement of about 2000-2500 kcal/d is frequently more difficult than providing a few dozen grams of protein and a few mg of various micronutrients per day.

Only the US (and its sphere of influence) has the opposite problem, because people there insist on drinking fizzy sugar water. It's not even that the maize the sugar is made from is low in micronutrients, it's that those aren't used to manufacture HFCS.

No. There are programs to teach people how to change crops from traditional crops to more nutrient rich crops, just to avoid what you are talking about. While true in areas where people are starving, any calories are good, but still in most parts of the world, people need nutrition to grow and be healthy. Our bodies can balloon up with fat and still be under nourished, and nutrient poor foods do this.

We could always just eat more of it. No one is at risk of getting too many calories from plants.

Or produce extracts.

This article is pretty bunk and politically/ideologically motivated.

Here’s the study, http://doi.org/10.1029/2019GH000188 which builds on https://doi.org/10.1126/sciadv.aaq1012

What part did you think was “bunk”?

It seems fairly predictable/uncontroversial that substantially changing the composition of the air plants are grown in would affect their growth. These studies are part of an effort to figure out precisely what changes result from expected current/near-future changes in the atmosphere and what potential impact those changes might have on the global food supply and health.

It is important to know about these effects so that we can try to mitigate the harms involved, e.g. by switching to new crops or crop strains, adopting alternative agricultural methods, supplementing at-risk diets with other foods, etc., instead of just letting millions of people suffer dangerous nutrient deficiencies.

On a quick read of the paper (thanks for the link) I was bothered that I found no mention of the fact that the per-acre yield also goes up with increased CO2. Each grain of rice (likely) has slightly less nutrients, but more grains of rice are produced in a given field. From other articles I found, it looks like the yield is expected to increase by about 13%. Omitting any mention of this feels like a political decision.

It's also worth noting that the paper doesn't really try to prove that nutrition levels will drop, but instead concentrates on showing that if nutrition levels in rice drop that more people may experience deficiencies. In particular, it cites a paper that actually did the experiment, and found no decrease in nutrients other than Nitrogen: http://sci-hub.tw/https://doi.org/10.1016/j.fcr.2004.01.004. This experiment implies that it's at least possible to grow rice under high CO2 levels without experiencing the drop.

I also thought the mitigation section was odd. It points out that only a few countries currently fortify rice with Vitamin B. It notes that fortification is inexpensive and effective, although it would require a major effort to begin doing so in other countries. The paper also shows that nutrient deficiency is already a large problem, and that increase caused by a decrease in foliate levels in rice would only be 1.5%. Maybe a better conclusion would be that these countries should really be fortifying their rice?

I didn't think it was a bad paper, and it wasn't "bunk". I agree that knowing what sort of changes to expect from an increased CO2 level is a good thing. But it did seem like it might be pushing an agenda more than just trying to lay out the scientific conclusions.

You need read up on agriculture basics before posting junk comments.

> From other articles I found, it looks like the yield is expected to increase by about 13%. Omitting any mention of this feels like a political decision.

That is because CO2 enrichment as a way to increase yields is decades old common knowledge and a widespread practice in greenhouses. Just because you did not know that, does not mean there is a conspiracy here.

> It's also worth noting that the paper doesn't really try to prove that nutrition levels will drop

Because nutrient density decrease is something that has already happened: https://www.politico.com/agenda/story/2017/09/13/food-nutrie...

While... blunt... your comment is exactly right. I don't mention the definition of degree of polynomial when I write an algebraic geometry paper. The knowledge that CO2 increases yields is universal among scientists reading this paper.

Perhaps obviously, I disagree. It's not that every paper has to mention everything that's obvious, but my point was that the choice of how to frame the problem can be a political decision. There was no attempt to explain why micronutrient per serving of rice was the right metric, and I think using it can be misleading if the amount of rice grown changes for the same reason that the nutrients are dropping. And while "everyone knows" that yields will increase, there is disagreement on whether the increase in yield is dependent or independent of the change in nutritional value.

By the way, I liked your comment elsewhere in this thread about eating plain rice. But rather than lamenting that all the references are behind paywalls, I personally think it's better just to give the DOI's and a link to http://sci-hub.tw. Or even better yet, just link to the papers, profits of publishers be damned. The world is better off when more people read the actual science.

The issue here is the notoriously shit science media with no room for nuance.

This one goes in along with "SCIENTISTS CURE CANCER" in which you get potentially interesting findings that get blown horribly out of proportion by whatever rag that decides to post it, often with a political spin to boot.

It's especially weird since crop yields are up like 30-40% since 1988. Not that rice is especially nutritious in the first place. It's basically a bunch of carbs with miniscule levels of vitamins.

My god, that paper is absolutely terrible. The science one, while not without issues, is much much better. The title also sucks less.

OP did say article not study.

The bunk bit is micronutrient deficiency is only amongst the real poor, less than $2 per day.

Not the rich (US/Europe) or middle class or US/European poor.

And it's happening TODAY, they way forward to the problem, which ALREADY exists is to fix it by getting a variety of foods to the real poor.

Rice alone is always not enough, this is a today issue.

A - Stop pushing today's issues until 2050 to push CO2 agendas.

B - The real poor need cheap energy today, they die without it. It's not just a discussion point by the ultra rich on a Bulletin Board.

C - Other plants with the required micronutrients will become cheaper/increased yields with the increased CO2. So stop making up possible issues when it's a today issues.

>B - The real poor need cheap energy today, they die without it. It's not just a discussion point by the ultra rich on a Bulletin Board.

Fossil fuels need to stop being used altogether, and as quickly as possible. This means that it’s up to the wealthy nations who currently use the most CO2 per capita (https://www-cdn.oxfam.org/s3fs-public/file_attachments/mb-ex...) to drastically reduce their share.

And guess what happens if the price of fossil fuels doesn’t match the ecological impact and their use is not drastically scaled down?

It’s precisely the poorest of the world who will suffer the greatest consequences of global warming.

Mate, you want to see the poor suffer...then immediately ban all use of fossil fuels. THAT will cause suffering of levels unseen in modern times.

It’s not that simple. You don’t get to keep your wasteful jet-setting, SUV-driving, car-culture-oriented consumer lifestyle on the basis that any wholesale transition would harm poorer people—-on the contrary, it is the obligation of wealthy countries to radically curtail their own use of fossil fuels in order to allow poorer countries to continue basic necessities such as heating and nitrogen-fixed fertilizers from natural gas. The wealthy countries have the economic means to rapidly transition their economies away from fossil fuels. This technology must then be exported to poorer countries on a free or subsidized basis.

It is a massive win-win for rich countries to develop technologies to prevent pollution and transfer it to poorer countries at low or no cost. It's like cleaning your own house & then ensuring the neighbors don't dump trash in through the windows. Self-interest alone dictates this! And self-interest also says we should make sure the poor in highly-populated countries get the nutrition they need to live decent lives, rather than having so little to lose that they start wars!

You are not adequately calculating the economic effects of rapidly attempting to refactor an economy the size of the United States nor the trickle down effects on the world economy and all the poor countries you claim to wish to help. This is extremely hand wavey and over simplistic.

Yes, it’s hard; it will probably require greater mobilization than WWII and the Apollo program combined, but the longer the world waits, the harder it’s going to be and the faster that mobilization will need to occur.

http://folk.uio.no/roberan/t/global_mitigation_curves.shtml (BTW those scenarios are now extremely optimistic based on leaked drafts of the upcoming IPCC report)

But people should understand that this degree of mobilization is mostly necessary because we insist on subjecting ourselves to a capitalist mode of production based on endless growth. A much easier alternative is simply to shutdown large parts of the economy and transition the lost jobs into land conservation/stewardship and geoengineering, while providing a basic income for everyone else working only a couple of days per week. (See Degrowth.) No, this will not create “profit”. Yes, this will require a mass redistribution of wealth. The sooner people acknowledge that The Party is Over, the sooner they can move on to real solutions.

Capitalism works better than anything else in history. Party isn't over.

Let me ask you something: of the warming that is occurring now, what percentage is due to humans and what percentage is due to natural fluxes in climate?

If we were to disappear off the face of the planet tomorrow, what would happen to the climate? Would it cool or would it warm?

Why don’t you do the research yourself and find out? Unless you think you know the answers, in which case go ahead and cite your sources.

The truth is generally: humans have contributed to most of the warming since the beginning of the industrial revolution considering the near-doubling of CO2 in the atmosphere and that climate sensitivity is between 3.5 and 5.5°C. (https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019...)

If humans disappeared tomorrow, three things would happen:

1. The surface of the planet would immediately warm by at least 1°C due to the lack of pollution-sourced atmospheric aerosols (such as sulfur) from planes, ships, coal plants, etc.

2. The temperature would decline, but do so very very slowly due to CO2 remaining in the atmosphere for hundreds of years. (https://www.ipcc.ch/site/assets/uploads/sites/2/2018/10/SPM1...) This is why some sort of long term geoengineering involving carbon removal will probably be necessary even after halting all emissions.

3. Wild plant and animal populations would immediately begin to recover as their native habitats re-grew.

And yes, I agree: Capitalism is the best system for destroying our natural environmental as efficiently as possible — what some would call “the externalized costs of economic growth”. This system has clearly proven itself unworkable. Sure, maybe with enough regulation we could have equilibrated capitalism within the bounds of our ecosystem, but those changes would have needed to been made decades ago. Now, no more time remains even for reform.

<citation required>

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