Comment by culi | Hacker News Reader

Comment by culi | Hacker News Reader

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The real harm of pesticides is rarely talked about. The impact on human health, while important (particularly in the third world), is minimal compared to the ecological devastation its done to our soils (and therefore the quality of our food).

Today, one would have to eat eight oranges to derive the same amount of Vitamin A as our grandparents would have gotten from one. A study tracking 43 different types of vegetables found "reliable declines" in protein, calcium, phosphorus, iron, riboflavin, and vitamin C in the past half century for all 43 of these vegetables.[0] Estimates say mineral levels in our vegetables have dropped by up to 90% since 1914.[1]

Over 90% of all plants rely on mycorrhizal fungi for the MAJORITY of their nutrients. Our obsession with sterile soil has driven countless numbers of these species to extinction and continues to drive one of the largest, and most overlooked, ongoing mass extinctions today. It's not just pesticides either. Artificial phosphorus fertilizers impede the complex plant signaling dance necessary for plants to make this essential connection with these soil fungi

Even if you're not worried about the direct implications pesticides have to your risk of cancer or other diseases, you should absolutely be aware of the nutritional impacts they are having on our produce

[0] https://www.scientificamerican.com/article/soil-depletion-an...

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6163803/

This review disagrees wrt to those mineral amounts: https://www.sciencedirect.com/science/article/pii/S088915751...

Highlights

• Mineral nutrient composition of vegetables, fruits and grains is not declining. • Allegations of decline due to agricultural soil mineral depletion are unfounded. • Some high-yield varieties show a dilution effect of lower mineral concentrations. • Changes are within natural variation ranges and are not nutritionally significant. • Eating the recommended daily servings provides adequate nutrition.

(Note that the author is Senior Scientific Advisor, Bureau of Nutritional Sciences, Food Directorate, Health Canada, so maybe take that one with a grain of salt as well)

this article is the equivalent of "nothing to see here, move along".

what is natural variation range?

just because barren soils do happen naturally, doesn't mean we have to turn every place in the world barren with pesticides just so we can standardize one combine harvester size.

> this article is the equivalent of "nothing to see here, move along".

Is that bad? Given the replication crisis, it seems pretty reasonable to be skeptical of new studies, rather than taking every attention-grabbing headline at face value.

Sure, but besides the 5 studies the paper reviews, there's quite a few other papers that have covered this topic. And despite difficulties in acquiring high quality data for these types of analyses, none of those studies have found evidence against the claim

This isn't like psychology (which is at the heart of the replication crisis) where studies are really expensive (human subjects have a lot of regulation around them) and are usually only done once. This is something that has been replicated, at varying degrees of quality, quite a few times

Sure, here is a list of points from papers that directly cite the paper you shared:

- The nutrient concentration of fruits and vegetables in the U.S.A. has declined in the past 50–70 years. Organic management practices was shown to increase nutritional quality over conventional[0]

- Soil fertility enhances nutrient accumulation in fruits[1]

- At least 3 recent studies found median decreases between 5% to 40% or more in some minerals in groups of vegetables[2]

- Significant effects on nutrient content of cultivation methods[3]

- Decreases in iron content of vegetables in Australia over time [4]

I would also point out that the study you linked does very little to actually combat the claims made by such studies. For example, in its treatment of Mayer 1997, it notes some potential issues (e.g. not correcting for moisture content), but mostly just points out that Mayer stated further evidence is needed and did not try to establish a "cause-and-effect relationship". Then there's another "depleted soil" hypothesis study, which I myself don't make any claims in support of. Then is points out Davis et al. 2004 which is much more statistically rigorous. It finds that the data is really messy, but when grouped together there IS INDEED a statistically significant decrease in certain minerals. Then the article goes on to talk more about how the "soil depletion hypothesis" doesn't have support in this study as well. Then they point out another 2005 study that finds similar results as Davis 2004 except it finds statistically significant decreases in even more minerals. But then points out again that the data is messy.

In the end all of the studies handled showed a (statistically significant) decrease in mineral content. The main point seems to me that more research is needed to back up these claims but doesn't at any point provide evidence to the contrary.

[0] https://www.mdpi.com/2071-1050/12/21/8965

[1] https://www.sciencedirect.com/science/article/pii/B978012818...

[2] https://www.pulsus.com/scholarly-articles/global-food-produc...

[3] https://www.mdpi.com/2223-7747/11/2/169

[4] https://www.mdpi.com/2304-8158/11/1/56

So should I believe their science or my own tongue? The difference in taste between homegrown and "commercial" vegetables is night and day.

I'm not sure what your comment as to do with the comment of the person you're replying to.

You seem to be suggesting that you can determine the nutritional content of food by taste alone?

On the one hand the claim sounds absolutely fantastical right?

"The human tongue which is free is better than a million dollar analytical lab staffed with real scientists."

On the other hand, how did we know what to eat to keep ourselves alive before there were labs and science? Taste maybe? Maybe things taste good to us for survival reasons. Maybe our tongues serve a real and incredible purpose.

If we were to run with this idea then humans lacking in particular nutrients should be able crave specific foods that are abundant in the nutrients theyre lacking.

But we dont see this in people with diets that consist of low nutrient high calorie processed food. Instead they just keep eating and eating the same food and gaining weight while developing nutrient deficiencies.

With that said I have noticed that ovee the years I have been able to notice tje differencd between a need for caloroes and protein, but thats probably because I've experienced low blopd sugar enough to know the symptoms -- I get hangry.

Have you never heard the tale of that guy, lost at sea, who slowly stopped eating the normal parts of fish as he started to crave the eyes and other unusual parts? Wish I could remember his name. He blamed the change in cravings on a nutrient deficiency.

People who are starving will also often start having weird cravings for things like rocks and other substances likely to be high in certain minerals

That you can find bad eating habits doesn't disprove the notion that taste has something to do with nutrient content. Our senses are not distinct from our psyches. Why we might choose to eat in ways that are not good for us is not determined by the tongue alone, and even the capacity to taste can vary. (Of course, more than taste is engaged in determining what to eat. We select foods based on a variety of signs. We can be fooled, but just because a sign may be misinterpreted doesn't mean signs are irrelevant. It's not either/or.)

I've met people who dislike anything except chicken fingers. They dislike anything but a very restricted number of foods, often of mediocre quality. Why? I don't know. Maybe they were raised on mediocre diets. Maybe they suffer from rigidity. That doesn't mean I can't look at a two tomatoes and generally tell which one is likely more nutritious by tasting it.

> Note that the author is Senior Scientific Advisor, Bureau of Nutritional Sciences, Food Directorate, Health Canada, so maybe take that one with a grain of salt as well

Why would we take Health Canada in particular with a grain of salt?

I'm pretty sure the conclusions from that Scientific American article you reference have been thoroughly debunked[0]

[0] https://culinarylore.com/food-science:are-todays-fruits-and-...

Thanks for the link. The article you provided debunks a specific explanation for the reason for the decline. It debunks the idea that our soils have simply become depleted of minerals over time (something I myself did not state).

However, the claim that nutrition content of our produce has significantly declined is quite well supported. Check out this link showing related papers that cite or are cited by the principle study:

https://www.connectedpapers.com/main/65fb8cb3cdc165c416347e8...

I also have issues with the Scientific American article. I hear a lot of speculation that part of the blame is because of breeding for newer varieties that are larger but less nutrient dense. I also think this claim is really unsupported and don't like that it is echoed by the article. However, I think the article you linked is not actually debunking the central claim I'm alluding to, nor my proposed explanation for it

I'm more interested what happens, when we kill of the last of the insects by those pesticides, and the effect goes up the food chain. Considering the history and eg. killing of the sparrows (four pests campaign), the results might be a lot worse than adding checmically produced nutrients to our diet.

I don't know if you heard the part about the vast majority of plants being dependent on soil fungi for the majority of their nutrients

Sure commercial crops still make it to fruit because farmers take care to add the necessary fertilizers and plant hormones to keep them going, but rest assured that this is a major driver of plant extinction as well

Plants have the smallest trophic level. Without plants, there's no insects either. There's no way you could care about insect extinction and somehow not care about this issue

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