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Nutrient levels in retail grocery stores

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Re: Nutrient levels in retail grocery stores

#31

Post by philipkglass »

hirako2000 wrote: post #10
modeless wrote: post #2

I thought it was a little weird that they start off talking about "calcium, magnesium, and iron" and then immediately switch to talking about how vitamin C degrades over time in produce. OK sure, vitamin C can enhance iron absorption, but it doesn't do that for calcium or magnesium and, being atomic elements, they assuredly do not disappear from food in storage. When an article conflates things like this without call…

Not contradicting your view that the article isn't very diligent, but have you heard of oxidation? Atoms constantly react to the environment, they can bond with other atoms, form new compounds. Oxidation time varies, in the case of potassium it is very fast, the claims in the articles would stand. For vitamins, it also depends. I got into a rabbit hole a few years back, digging into numbers from multiple academic sou…

Not contradicting your view that the article isn't very diligent, but have you heard of oxidation?

Atoms constantly react to the environment, they can bond with other atoms, form new compounds. Oxidation time varies, in the case of potassium it is very fast, the claims in the articles would stand.

Potassium, calcium, and magnesium are always fully oxidized in foods. These elements are very reactive with water and oxygen; on Earth they are not naturally found in less oxidized forms.

Re: Nutrient levels in retail grocery stores

#32

Post by eykanal »

This article could use an awful lot more links to the cited research. Reading this as a skeptic, I don't know whether the claims are accurate or not, but the fact that (nearly) none of his claims are supported by citations to authoritative sources is not promising.

Re: Nutrient levels in retail grocery stores

#33

Post by TaylorAlexander »

tcfunk wrote: post #30
eltondegeneres wrote: post #28

> If you walk into a booth and that vendor is selling over 5 types of produce, there's no way they all ripened at the same time. They may not even all be grown by them. Once, he actually saw a vendor at Boston farmers’ market selling carrots from Target! He could tell from the packaging because he used to work for them. I don't think this is true. In California and New York City, vendors at farmers markets can only s…

My wife ran a farmer's market for years, it can definitely be true. Vendors tried to sneak stuff in constantly, and unless you have a market manager who really cares and is constantly vigilant, vendors will resell stuff they have bought in bulk and are reselling at a markup. Not all vendors of course, but like anything else there's always a handful of bad actors.

Yeah I have seen a farm do this! They bought from other local farms at least, not Target. But the claim "vendors at farmers markets can only sell what they grew themselves" is only true to the extent that there is enforcement and sufficient oversight to find violators.

Re: Nutrient levels in retail grocery stores

#34

Post by afpx »

eltondegeneres wrote: post #28

> If you walk into a booth and that vendor is selling over 5 types of produce, there's no way they all ripened at the same time. They may not even all be grown by them. Once, he actually saw a vendor at Boston farmers’ market selling carrots from Target! He could tell from the packaging because he used to work for them. I don't think this is true. In California and New York City, vendors at farmers markets can only s…

Is this regulated by the state? In VA, I often see farmers market vendors selling produce that they purchased from the distributors or wholesalers.

Re: Nutrient levels in retail grocery stores

#35

Post by miltonlost »

giarc wrote: post #13
modeless wrote: post #2

I thought it was a little weird that they start off talking about "calcium, magnesium, and iron" and then immediately switch to talking about how vitamin C degrades over time in produce. OK sure, vitamin C can enhance iron absorption, but it doesn't do that for calcium or magnesium and, being atomic elements, they assuredly do not disappear from food in storage. When an article conflates things like this without call…

It's an odd article all around. Look at the first graph. It's an average mineral content of calcium, magnesium, and iron in 4 different vegetables, but only represented by a single line. Why isn't it broken out for each category (ex. iron in tomatoes over time)?

The first graph is also 5 data points connected by a line and separated by decades and most likely differing methodlogies. And this footnote

> "The chart has unverified information "The average mineral content of calcium, magnesium, and iron in cabbage, lettuce, tomatoes, and spinach has dropped 80-90% between 1914 and 2018 30,34,35,36,371. Asterisks indicate numbers could not be independently verified."

What is this chart and data? It's meaningless and nonsensical. And so the rest of the article is suspect when based on unverifiable nothing.

Re: Nutrient levels in retail grocery stores

#36

Post by miltonlost »

eykanal wrote: post #32

This article could use an awful lot more links to the cited research. Reading this as a skeptic, I don't know whether the claims are accurate or not, but the fact that (nearly) none of his claims are supported by citations to authoritative sources is not promising.

Literally the author states it's unverifiable data:

The chart has unverified information "The average mineral content of calcium, magnesium, and iron in cabbage, lettuce, tomatoes, and spinach has dropped 80-90% between 1914 and 2018 30,34,35,36,371. Asterisks indicate numbers could not be independently verified."

Re: Nutrient levels in retail grocery stores

#37

Post by krunck »

"It's a well-documented phenomenon that nutrient levels in produce have been declining for decades. ... There are several reasons for this, but most of them are due to modern agricultural practices. These reasons include: ... higher CO2 levels in atmosphere diluting nutrient content in plants, ... "

The author then links to an X post with a chart that shows relative carbon and nitrient levels and that says that "exposure to high levels of CO2 reduces the nutritional value of plants". It's not clear to me from the chart that spinach raised in high CO2 levels would contain less nutrients per kilogram than regular spinach. The chart only show proportions of the nutrients to carbon. Does the amount of carbon per kilogram of edible spinach stay the same or go down as CO2 increases? It's not clear.

Re: Nutrient levels in retail grocery stores

#38

Post by karldcampbell »

modeless wrote: post #21
hammock wrote: post #18

Earlier quoted context omitted.

You’re sort of mixing ideas I believe. The nutrient density (minerals etc) is declining because of the soil quality it is grown in, not because it is sitting on shelf. The vitamin C thing was about nutrient loss due to blanching (a processing step) I believe

The article is mixing ideas, is the point. If soil quality matters, that seems to contradict the article's claim that speed is the only thing that matters.

The article is from the comsumer's perspective. For me, someone who doing my daily / weekly shopping, time-from-harvest is the only factor I can use in a purchasing decision. I can't rely on branding, source, grower etc as all that is a crap-shoot. Even if one grower has nutritious tomatoes this year, next year they might use a different field leading to worse nutrition.

Re: Nutrient levels in retail grocery stores

#39

Post by red-iron-pine »

hammock wrote: post #12
hansonkd wrote: post #4

> That means it had been a year since the apples he bought were actually picked I've been saying for a while that instead of focusing on "best by" dates, food suppliers should be forced to put on the harvest or manufactured date. "Fresh" Apples being sold after a year is nothing compared to how old some of the food you by in the freezer, or boxed section. Manufacturers and store owners are the ones that benefit the m…

Frozen vegetables are often blanched and flash frozen at the peak of freshness. In many cases they are “fresher” than what you find in the produce section

many of the "fresh" verities are also grown explicitly for hardiness and transportability, and are often also not great in terms of taste or texture.

freezing meanwhile can preserve them on the spot and ensure the less transportable types can make it to consumers.

Re: Nutrient levels in retail grocery stores

#40

Post by BizarroLand »

modeless wrote: post #21
hammock wrote: post #18

Earlier quoted context omitted.

You’re sort of mixing ideas I believe. The nutrient density (minerals etc) is declining because of the soil quality it is grown in, not because it is sitting on shelf. The vitamin C thing was about nutrient loss due to blanching (a processing step) I believe

The article is mixing ideas, is the point. If soil quality matters, that seems to contradict the article's claim that speed is the only thing that matters.

They're saying how fast the food goes from farm to table is what matters.

Doesn't matter if you grow old variety organic seeds the slow way in small batches on virgin soil if it takes 11 months for the food to get to your mouth.

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