Is our food still what it used to be? A question that is vehemently answered in the negative on the Internet. The fields are said to be depleted and over-fertilised. The food industry is doing its part to completely devalue our food. Udo Pollmer examines the data and commercial interests involved.
by Udo Pollmer August 29, 2024
I hear and read that the nutrients in our food are disappearing. Many vitamins, minerals and trace elements have disappeared, as comparisons with older nutritional value tables show. The losses are dramatic.1-3 It started with over-fertilised and depleted soils.
Over-fertilised and depleted serves a...
...strange idea: too many nutrients in the field and too few at the same time. One might argue that there is too much of one and too little of the other. But if important nutrients are missing, neither plants nor animals will grow. As farmers want to make a living from their yields, they usually make sure that their crops and livestock thrive.
Over-fertilising costs money and is now being prosecuted by the authorities. Today, they use satellites to determine the amount of mineral or natural fertiliser on each field by looking at the greening of the fields. All that remains is a lack of trace elements. But trace element fertilisers are available everywhere. Interested parties can marvel at entire shelves in DIY stores where they can buy the right mix for almost any plant. For farmers and gardeners, this is as banal as the pharmacist's pills.
Of course, the need for trace elements and minerals has changed over the decades: In the past, many of these nutrients came by air: the chimneys of waste incineration and industrial plants blew everything into the atmosphere unhindered. Not only soot wafted across the land, but also trace elements such as sulphur from lignite or rare earths from electronic waste.4 The increase in car exhaust gases also ensured better forest growth due to their nitrogen content.5
This changed with air pollution control. Since then, farmers have been fertilising with sulphur, especially their rapeseed fields. That used to be superfluous. Some people miss the trace elements in the air, others are happy about the cleanliness. Of course, there are still over-fertilised areas, even in nature reserves. Trees and greenery rot there without being harvested. With the thin humus layer of the forest floor, the resulting nitrate seeps away unused and can cause increased nitrate levels in the groundwater, depending on the geological subsoil.6
It's no different with livestock, which is also always given mineral feed and vitamin cocktails. There's an extra in everything to make sure it's enough. The risk of overdosing is rarely considered. Yet this thought is not so far-fetched. When growth promoters were banned in pig fattening, farmers fed zinc as a prophylactic measure. It was used so abundantly in the stables that the pig slurry overloaded the fields with it.7,8 Zinc levels had to be limited for reasons of soil and health protection. Above all because zinc quickly provokes resistance to common antibiotics in animals and humans.9
As valuable as a small steak
Take selenium, for example. When US chemists checked the selenium content of foods and compared it with their nutritional tables, they made an unpleasant discovery. There was often no correlation between the data in the official tables and the measured levels. It was not uncommon for the foods to contain one to two powers of ten more. And there were considerable fluctuations: In the case of wheat, the levels per 100 grams were between 10 µg and 800 µg.10 For comparison: In Germany, the selenium content is given as around 2 µg.11 That's a lot less, if it's true. Are our soils depleted after all?
The levels of selenium in local beef are rising rapidly. While they have hovered around 5 µg per 100 grams for decades, they are now said to be up to ten times higher, depending on the source - a consequence of agriculture's liberal use of trace elements. With the aforementioned fluctuation ranges, average values in the tables are as informative as toilet paper with flowers printed on it.
According to the German Nutrition Society (DGE), vegetarians have a lower selenium intake than normal people. Which selenium supplier does our professional organisation recommend? That's right! "Broccoli" is at the top of their list.12,13 Unfortunately, there is virtually no selenium in it; according to the nutritional table referred to by the DGE, the content is 700 ng per 100 grams - nanograms.11 A wet fart is more nutritious. But perhaps the figure of 700 has blinded the experts?
By the way: selenium is also found in chocolate. According to the Max Rubner Institute, chocolate contains 33 µg/100 g, which is 50 times more than what you get in broccoli.14 Even if you take the lower values of the Federal Office of Consumer Protection and Food Safety as a basis, a whole bar is as valuable as a small steak.15 Why doesn't the DGE recommend that vegetarians eat a bar of whole milk nuts every day instead of bitter cabbage?
Making one's hair stand on end
In view of the rapid increase in levels in food, the question is whether it is not already too much of a good thing? The European Food Safety Authority (EFSA) recently lowered the safe upper intake level for adults from 300 to 255 μg per day on the basis of a large randomised, controlled study (SELECT).16 This means there is no risk of an overdose, at least with chocolate.
The US wheat flakes with 800 µg per 100 grams are different. Anyone who gives it to their children in muesli every day is exposing them to unnecessary health risks. This is because chronic poisoning has already been observed with 800 µg of selenium per day,17 according to the DGE in 2000.18
The first signs of an overdose are blemished skin, damaged nails and hair loss. But this is exactly what "selenium" is preferably taken for. In an intervention study over 5 years with 300 µg extra selenium per day, mortality increased. The fatal effect continued in the same way for ten years even without supplements.19
The margin between benefit and poisoning is damn small. This has long been known from animal nutrition: as early as 1998, the Swiss nutrition report warned: "Depending on the natural selenium concentrations in feed, either deficiency or poisoning is observed in livestock worldwide."20 So be careful with unreflected recommendations.
Instead of the usual "requirement figures", there is an "adequate intake" for selenium. The reason for the subtle distinction: the latter is estimated by the DGE from "estimated values". In 2000, the "adequate intake" was still 30 to 70 µg per day.18 This was already twice as much as the WHO had recommended.21 Today, the lower value is 60 µg instead of 30 µg, i.e. "estimated" by the DGE. I reckon that's all just rubbish.
The fact that the supposedly safe upper limit was lowered almost silently by the EU shows how easy it is to misjudge. But unimpressed by the toxicological explosiveness and the simultaneously good supply, supplements are diligently advertised, soils are irreversibly contaminated with selenium and livestock are served selenium-enriched feed. The supplements, just like food and feed, contain a wide range of different selenium compounds, all with different effects, but all labelled as "selenium".
Off to Africa!
The levels in food are one thing, absorption in the digestive tract is another. Many elements influence each other: zinc slows down the absorption of selenium, and selenium slows down the absorption of zinc.22 This is one of the reasons why diabetics sometimes benefit from zinc supplements: Increased selenium intake has long been considered a cause of diabetes.23-28 Animal experiments have shown that the antioxidant effect of selenium (through glutathione peroxidase) is responsible for insulin resistance.29
A human trial with selenium-rich fish had no effect on blood selenium levels.30 In Norway, people wondered why citizens had some of the highest selenium levels in their blood in Europe despite a rather moderate intake.31 In Finland, the low selenium levels in arable soil were to be doubled within 20 years through a nationwide fertilisation campaign. After two years, they had already tripled.32 Selenium is unpredictable.
Even though Germany, and indeed the whole of Europe, has been declared a "selenium deficiency area" by the dealers, according to surveys by the Max Rubner Institute, Germans are well supplied with selenium.14 But of course there are also areas of deficiency. The DGE cites the high altitudes of Central Africa first and foremost.13 There, their tastefully dressed dieticians would certainly be a picturesque addition to the landscape.
"True values"
The siren calls of influencers are unmistakable on the internet, and the annoying chirping of dietitians can be heard from health posters, claiming that nutritional values have fallen dramatically in the last 100 years. They compare nutritional value tables from the old days with new works. From the large number of foods, they pick out a few with just the right ingredients and show the loss. Sometimes the loss seems gigantic, sometimes it is only a few per cent, which would be due to measurement inaccuracy alone.1-3 But they reinforce the impression that there is less everywhere.
When it is claimed that apples now only have one milligram of vitamin C per 100 grams instead of 5, the advisors are targeting the public's ignorance. The vitamin C content of apples depends on the variety. There are varieties rich and poor in vitamin C, just as there are those with red apple cheeks and those of a pale green colour. Of course, it is also a question of storage. Comparable results require the same harvest year, the same variety and storage. There is still just as much in it today as there was when Grandad was still young.33 New varieties show the same range of vitamin C as the old ones.34
Not to forget: The calcium content of fruit does not depend on the leaching of the soil, but on whether the harvest was treated with calcium to increase the shelf life. The sodium content indicates whether the apples were exposed to a salty sea breeze, as in the Altes Land, a region near the North Sea or whether they were allowed to travel from the Lake Constance area. This has absolutely nothing to do with a lack of nutritional value.
Let's not forget that data from the early days of analysis cannot be compared with the results of today. Analysis has developed over 100 years and colleagues have constantly devised new, more reliable methods to track down trace substances in food. Every expert knew that their results were not "true values", but values that could be reproduced using a defined methodology. The laboratory methods of the past are as different from today's methods as the first motorised car is from the Formula 1 racing cars.
Pure Nonsense
Even when it comes to processing, almost nothing is comparable. A curd cheese produced today has a different composition than 60 years ago.35 Not because the milk is worthless or the cow has been overbred, but because customers bought the cheaper product, preferably the one with more water in it. Because it's lower in calories! The fewer calories, the less nutritious the product is. And nutritionists are already complaining about a lack of nutrients caused by an unscrupulous industry. And yet, as the originators of the diet mania, they have always recommended paying attention to calories.
If someone wants to deceive the public, it can be shown at any time how the industry devalues our food: Compare the highest selenium content in American wheat, at 800 µg per 100 grams, with the lowest - the flakes from a large muesli factory - at 10 µg. Anyone can see how US companies are messing up our food. In reality, muesli flakes simply reflect the selenium content of the soil. It has nothing to do with a devaluation of the nutritional value. The plants are not interested in Selenium because it neither benefits nor harms them. They absorb selenium according to the levels in the soil.16
In the face of such confusion, how do we get objective results on selenium supply or exposure, let's say, in the time before industrialisation? Quite simply: in England. Cultivation trials have been carried out at the famous Rothamsted Agricultural Experimental Station since 1844. The analysis of the retained samples showed that the selenium content in wheat rose continuously from the start of the trials until 2007, the date of the analysis, with certain fluctuations. This shows that selenium is an anthropogenic environmental pollutant, presumably due to the mining and burning of coal in earlier times.36
The data from Rothamsted show that it did not matter whether and how fertiliser was applied, whether modern high-performance varieties were grown or old landrace varieties. The selenium content was not affected.37 In southern Spain, it was found that the selenium content of the harvests varied greatly from year to year, with no recognisable influence of the cultivation method or the amount of rainfall.38
Is selenium good for nothing?
Yes, the element is effective in the so-called Keshan disease, which occurs or has occurred in remote regions of China, North Korea, Far Eastern Russia and South Africa.39-41 It is caused by poisoning from mouldy rice, rotten maize or fungal millet.42,43 The cardiotoxic mycotoxins responsible are called citreoviridin and moniliformin.44-46 In times of food shortages, a poor population also eats mouldy stocks.
There is now a very similar disease of the heart, shoshin kakke, also known as cardiac beriberi.47 It is associated with Keshan disease.46,48 The antidote for beriberi is called thiamine. The well-known vitamin B1 helps the liver to detoxify.49 Thiamine is also effective in Keshan patients.50 Like citreoviridin, moniliformin slows down pyruvate dehydrogenase and presumably also α-ketoglutarate dehydrogenase, both of which are thiamine-dependent.51 The mould toxin also inhibits cardiac glutathione peroxidase.52 This is precisely where selenium has a detoxifying effect because it is a component of the enzyme's catalytic centre.
Selenium is a good antidote for this mycotoxicosis. The mercantile theory that selenium deficiency is the cause of Keshan disease is ruled out because it shows a seasonal pattern.53 It occurs in late winter and spring, when conditions are favourable for mould growth during storage in huts.54 If selenium deficiency is the cause, then Aspirin® deficiency is the cause of headache.
Fallen among the robbers
Many people are convinced that they have been disadvantaged, believing that their notoriously bad mood, vulgo vegetative dystonia, is due to farmers exploiting their land or sinister corporations further devaluing the now impoverished harvests. Sugar, in particular, is a thieving fellow in the delusional worlds of snappy health eaters. It steals wherever it can, preferably vitamins and minerals. In reality, it is completely digested: into carbon dioxide and water. So it can't take anything with it. Nothing is left over and nothing is missing.
The noble wholemeal is completely different, as it does not release its minerals and trace elements in the intestine because they are firmly bound in the bran. With ingredients such as phytin, whole grains are even able to fish minerals out of the digestive mash and expel them with the bran. Wholemeal is considered a malnutrition due to highly unpleasant historical experiences.55-59 It causes deficiencies, particularly in zinc, but also removes other elements such as magnesium and selenium.60,61 Thanks to phytin and vegetable fibres, the losses from a healthy diet are considerable.
In this respect, there are certainly situations in which the targeted administration of a mineral or trace element is helpful. Deficiencies are not surprising, especially with a "healthy diet". Regular consumption of laxatives also removes zinc.62 A deficiency is often also the result of an excess of a counterpart consumed as a supplement. For example, too much calcium causes a phosphate deficiency and vice versa. Sometimes minerals are also prescribed therapeutically: Magnesium, for example, is effective against cramps, even if there is no deficiency.
English Editor: Josef Hueber
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