Dec 7, 2023 06:00 PM
(This post was last modified: Dec 7, 2023 06:45 PM by C C.)
As they say, it's pretty much irrelevant, anyway, if most people are eating junk slash processed food and animal products, instead of more vegetables, fruits, nuts, etc.
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https://www.chemistryworld.com/features/...78.article
EXCERPT: In several papers, researchers have used food tables – country-by-country compendia of historical information on the mineral composition of foods – to report an apparent decline in micronutrients such as iron, vitamins and zinc in fruit and vegetables over time.
One study on this subject dates back to 1997, when Anne-Marie Mayer, a nutrition consultant in the UK, looked at the composition of the UK government’s food tables. She compared the mineral content of 20 fruits and 20 vegetables reported in the 1930s to those in the 1980s and found that the 1980s batch had lower levels of magnesium, copper and other micronutrients. In 2004, a team in the US carried out a similar analysis, comparing the nutrients in 43 raw vegetables commonly grown in home gardens in 1950 and 1999. They found an apparent decline in six nutrients (protein, calcium, phosphorus, iron, riboflavin and vitamin C) in the later batch.
However, while both papers show a clear decline over time, the authors of the latter explicitly state in the conclusion that their paper can’t confirm with certainty whether there is a real decline in nutrients in staple foods. This is because the data they used, taken from food tables, struggles to provide a clear answer.
[...] for all its benefits, the Green Revolution seems to have had one unwanted consequence. Comparing Green Revolution wheat varieties with older varieties, McGrath and his colleagues found that modern varieties contained fewer minerals when grown under the same conditions and side by side with older varieties. This suggests that the decline in micronutrients is not due to environmental factors, but to something happening inside the plant.
‘It’s not a soil effect, it’s not a seasonal effect […] It’s the fact that the genetics changed, and the allocation of nutrients has changed,’ McGrath concludes. He explains that the plant is putting more of its carbohydrates, its production, into the grain and less into the straw. The increase in carbohydrates dilutes other grain components, including minerals. So although we see higher yields, the grains themselves are poorer in micronutrients: average concentrations of zinc, copper, iron and magnesium in the grain of the newer varieties were 19–28% lower than those of the older ones.
These results provide some answers to the question of whether the nutrient content of our food is changing, although they only look at one crop (wheat) in one country (England).
[...] There’s no denying that the amount of carbon dioxide and other greenhouse gases in the atmosphere has been rising steadily for decades. And while hundreds of species will be adversely affected, some plants may actually thrive. ‘Plants evolved when carbon dioxide was much higher than today, so for about 90–95% of them, the current carbon dioxide concentration is less than optimal. More carbon dioxide stimulates photosynthesis and growth,’ says Lewis Ziska, professor of environmental health sciences at Columbia University in New York, US.
But bigger isn’t always better. And though growing more plants may mean more food, the amount of nutrients in that food may be far from ideal for human nutrition...
[...] Another pathway that could explain the reduced rate of micronutrients relates to water efficiency. ‘When plants grow in this higher concentration of carbon dioxide, they’re more water efficient. So, they bring in less water, which means they bring in less micronutrients from the soil,’ adds Ebi.
[...] Fortified crops could be one way of tackling this problem in regions where people are more likely to be affected. Adapting the way we grow food is another. Ebi mentions that changing farmers’ rewards could be a step forward. ‘The incentive for farmers is how much they produce, not the quality of what they produce. And if you could change the incentives, our farmers could be rewarded for having higher nutrient density [crops],’ she says.
But in the grand scheme of things, does all this mean you need to boost your diet right away? Not really. The use of supplements may come to mind, and indeed supplement companies tend to exploit these findings to promote their products. However, it seems that the best approach is still to follow the usual dietary guidelines, especially at a time when fruit and vegetable consumption in European countries is still far from ideal.
‘Most people don’t have the portions of fruit and vegetables that they should. It’s not much more than 10% to have more than five portions across the EU. And we’re talking about a highly privileged continent, so that’s a problem in itself,’ Trigueiro says.
In the UK, vegetables make up a meagre 6.3% of the average shopping basket... (MORE - missing details)
- - - - - - - - - - -
https://www.chemistryworld.com/features/...78.article
EXCERPT: In several papers, researchers have used food tables – country-by-country compendia of historical information on the mineral composition of foods – to report an apparent decline in micronutrients such as iron, vitamins and zinc in fruit and vegetables over time.
One study on this subject dates back to 1997, when Anne-Marie Mayer, a nutrition consultant in the UK, looked at the composition of the UK government’s food tables. She compared the mineral content of 20 fruits and 20 vegetables reported in the 1930s to those in the 1980s and found that the 1980s batch had lower levels of magnesium, copper and other micronutrients. In 2004, a team in the US carried out a similar analysis, comparing the nutrients in 43 raw vegetables commonly grown in home gardens in 1950 and 1999. They found an apparent decline in six nutrients (protein, calcium, phosphorus, iron, riboflavin and vitamin C) in the later batch.
However, while both papers show a clear decline over time, the authors of the latter explicitly state in the conclusion that their paper can’t confirm with certainty whether there is a real decline in nutrients in staple foods. This is because the data they used, taken from food tables, struggles to provide a clear answer.
[...] for all its benefits, the Green Revolution seems to have had one unwanted consequence. Comparing Green Revolution wheat varieties with older varieties, McGrath and his colleagues found that modern varieties contained fewer minerals when grown under the same conditions and side by side with older varieties. This suggests that the decline in micronutrients is not due to environmental factors, but to something happening inside the plant.
‘It’s not a soil effect, it’s not a seasonal effect […] It’s the fact that the genetics changed, and the allocation of nutrients has changed,’ McGrath concludes. He explains that the plant is putting more of its carbohydrates, its production, into the grain and less into the straw. The increase in carbohydrates dilutes other grain components, including minerals. So although we see higher yields, the grains themselves are poorer in micronutrients: average concentrations of zinc, copper, iron and magnesium in the grain of the newer varieties were 19–28% lower than those of the older ones.
These results provide some answers to the question of whether the nutrient content of our food is changing, although they only look at one crop (wheat) in one country (England).
[...] There’s no denying that the amount of carbon dioxide and other greenhouse gases in the atmosphere has been rising steadily for decades. And while hundreds of species will be adversely affected, some plants may actually thrive. ‘Plants evolved when carbon dioxide was much higher than today, so for about 90–95% of them, the current carbon dioxide concentration is less than optimal. More carbon dioxide stimulates photosynthesis and growth,’ says Lewis Ziska, professor of environmental health sciences at Columbia University in New York, US.
But bigger isn’t always better. And though growing more plants may mean more food, the amount of nutrients in that food may be far from ideal for human nutrition...
[...] Another pathway that could explain the reduced rate of micronutrients relates to water efficiency. ‘When plants grow in this higher concentration of carbon dioxide, they’re more water efficient. So, they bring in less water, which means they bring in less micronutrients from the soil,’ adds Ebi.
[...] Fortified crops could be one way of tackling this problem in regions where people are more likely to be affected. Adapting the way we grow food is another. Ebi mentions that changing farmers’ rewards could be a step forward. ‘The incentive for farmers is how much they produce, not the quality of what they produce. And if you could change the incentives, our farmers could be rewarded for having higher nutrient density [crops],’ she says.
But in the grand scheme of things, does all this mean you need to boost your diet right away? Not really. The use of supplements may come to mind, and indeed supplement companies tend to exploit these findings to promote their products. However, it seems that the best approach is still to follow the usual dietary guidelines, especially at a time when fruit and vegetable consumption in European countries is still far from ideal.
‘Most people don’t have the portions of fruit and vegetables that they should. It’s not much more than 10% to have more than five portions across the EU. And we’re talking about a highly privileged continent, so that’s a problem in itself,’ Trigueiro says.
In the UK, vegetables make up a meagre 6.3% of the average shopping basket... (MORE - missing details)