this post was submitted on 29 Mar 2024
256 points (99.2% liked)

News

23645 readers
4200 users here now

Welcome to the News community!

Rules:

1. Be civil


Attack the argument, not the person. No racism/sexism/bigotry. Good faith argumentation only. This includes accusing another user of being a bot or paid actor. Trolling is uncivil and is grounds for removal and/or a community ban. Do not respond to rule-breaking content; report it and move on.


2. All posts should contain a source (url) that is as reliable and unbiased as possible and must only contain one link.


Obvious right or left wing sources will be removed at the mods discretion. We have an actively updated blocklist, which you can see here: https://lemmy.world/post/2246130 if you feel like any website is missing, contact the mods. Supporting links can be added in comments or posted seperately but not to the post body.


3. No bots, spam or self-promotion.


Only approved bots, which follow the guidelines for bots set by the instance, are allowed.


4. Post titles should be the same as the article used as source.


Posts which titles don’t match the source won’t be removed, but the autoMod will notify you, and if your title misrepresents the original article, the post will be deleted. If the site changed their headline, the bot might still contact you, just ignore it, we won’t delete your post.


5. Only recent news is allowed.


Posts must be news from the most recent 30 days.


6. All posts must be news articles.


No opinion pieces, Listicles, editorials or celebrity gossip is allowed. All posts will be judged on a case-by-case basis.


7. No duplicate posts.


If a source you used was already posted by someone else, the autoMod will leave a message. Please remove your post if the autoMod is correct. If the post that matches your post is very old, we refer you to rule 5.


8. Misinformation is prohibited.


Misinformation / propaganda is strictly prohibited. Any comment or post containing or linking to misinformation will be removed. If you feel that your post has been removed in error, credible sources must be provided.


9. No link shorteners.


The auto mod will contact you if a link shortener is detected, please delete your post if they are right.


10. Don't copy entire article in your post body


For copyright reasons, you are not allowed to copy an entire article into your post body. This is an instance wide rule, that is strictly enforced in this community.

founded 2 years ago
MODERATORS
 

In 2004, Donald Davis and fellow scientists at the University of Texas made an alarming discovery: 43 foods, mostly vegetables, showed a marked decrease in nutrients between the mid and late 20th century.

According to that research, the calcium in green beans dropped from 65 to 37mg. Vitamin A levels plummeted by almost half in asparagus. Broccoli stalks had less iron.

Nutrient loss has continued since that study. More recent research has documented the declining nutrient value in some staple crops due to rising atmospheric carbon dioxide (CO2) levels; a 2018 study that tested rice found that higher CO2 levels reduced its protein, iron and zinc content.

While the climate crisis has only accelerated concerns about crops’ nutritional value, prompting the emergence of a process called biofortification as a strategy to replenish lost nutrients or those that foods never had in the first place.

you are viewing a single comment's thread
view the rest of the comments
[–] The_v 24 points 9 months ago (3 children)

There are many things that are unsupported in this article

First off, the laboratory methodology changed for testing food. Modern testing techniques much more accurate than the ones in the 50's and 70's. They did not run the older methodologies on modern food. So basically the entire premise is comparing apples to oranges. We don't know if the changes are due to reality or procedure changes.

The second study on rice had me smiling. From somebody who knows nothing about breeding cereal grain it would seem to be a slam dunk, however reality is more complicated. All cereal breeders struggle with the tradeoff between maximizing yield and lodging resistance. Lodging is when the stalk falls over. When it falls over major yield losses can occur (50%+ depending on the stage). It also causes major difficulties with harvesting on equipment and time. Extra CO2 increases plant size and kernal size. A taller plant with a heavier seed head that a slight breeze will knock over. Breeders will select genetically smaller kernals and smaler stature plants to compensate for increasing CO2. This is the major reason that all hybrid wheat attempts have failed. It makes a huge plant that falls over.

Some basics on nutritional density of vegetables.

Fruit size: in general the larger the fruit lower the nutritional density. The plant only has so much it can create or pull from the soil.

Nutrient density is affected by position on the plant where it is grown. Earlier set fruit tend to have higher nutritional density than later set fruit. You can look up more on this on source/sink studies.

Nutrient availability: plants that are slightly nutritionally deficient will produce smaller fruits/seeds. The smaller size will make the fruit more nutrient dense.

The weather is the single largest determining factor. When a plant is happy with ideal conditions the nutrient density is lower. When the plant is stressed and grows more slowly, it produces less yield with higher density food.

Genetics: Sometimes plant breeders select for higher nutritional density like watermelons. Sometimes they select for lower density like strawberries. It all depends on the market requirements.

[–] [email protected] 3 points 8 months ago (1 children)

Thanks for sharing these details.

Noob question: if I eat a huge apple or a small apple, but eat them full, wouldn't I effectively get same amount of nutrients?

[–] The_v 4 points 8 months ago

You would get similar amounts of total nutrients however, you'd eat more carbohydrates. The larger apple has less nutrient density.

[–] feedum_sneedson 1 points 8 months ago (1 children)

Every discussion on food production is like this. Nowhere on the internet have I seen more people confidently spouting absolute nonsense as if it were expert testimony.

[–] The_v 2 points 8 months ago (1 children)

To be fair:

I have seen lot of nonsense spouted by the "experts." PhD levels who are making bad assumptions outside of their field of expertise. I would say only about 1 in 10 papers I read is worth the time to download it.

It's an ongoing issue with the high level of specialization in the sciences, especially in academia. Any topic which covers multiple disciplines turns into a clusterfuck.

[–] feedum_sneedson 1 points 8 months ago

Yes, it's shocking what gets published nowadays.

[–] [email protected] 0 points 8 months ago (1 children)

It all depends on the market requirements.

But that's the problem. Capitalism should never have been allowed to effect what a tomato or apple looked like vs the nutritional value it had. And in some (many?) cases that's what happened.

[–] The_v 6 points 8 months ago (1 children)

Market requirements are not necessarily driven by capitalism.

Throughout history, needs of the culture determine the plant breeding efforts. Often flavor and nutrition have been traded for yield and storage.

For example the absolute worst watermelon I ever ate was in Uzbekistan. The soviet's created a long-storage melon that lasts up to 10 months. It's was about as bad as eating cardboard.

[–] [email protected] -2 points 8 months ago (1 children)

At a fundamental level the "need" for a long-storage watermelon developes out of capitalism, not a populace's needs.

[–] feedum_sneedson 2 points 8 months ago* (last edited 8 months ago)

No, that's not correct. The need is for food.