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Nutrients in our food are declining. Can regenerative agriculture save it?
- In the late 90s, the US Department of Agriculture found the vitamin C content of lemons had decreased by almost a third over the previous 22 years.
- Calcium in carrots, an important source especially for non-meat eaters, had reduced, on average, by more than a quarter.
- Vitamin A in bananas was down by 57%.
Approach focuses on rebuilding soil health, increasing biodiversity and restoring natural ecosystems For the last few decades, the nutrient content of our crops has been declining. In the late 90s, the US Department of Agriculture found the vitamin C content of lemons had decreased by almost a third over the previous 22 years. Calcium in carrots, an important source especially for non-meat eaters, had reduced, on average, by more than a quarter.
Vitamin A in bananas was down by 57%. The mineral content of wheat has declined by between 20-30% since the 1960s. A number of reasons have been suggested for this worrying decline, ranging from new varieties of crop that are bred to grow quicker and bigger to the higher carbon dioxide levels in the air causing plants to produce more sugars and starches (they grow faster but they produce fewer nutrients). A wide range of fixes have been suggested, from GM crops to synthetic soil amendments, or underground farms. lcium content in carrots fell by more than a quarter between the mid-1970s and the last 1990s, according to the US Department of Agriculture.
José Sánchez/AP Nutrients in our food are declining.
One group of agricultural researchers, however, argues that the answer to declining nutrients may be more straightforward than that: regenerative agriculture. This “focuses on building organic matter and ecosystems in the soil”, says Francesca Brkic.
“The question is, does that therefore deliver more nutrition? Her work, in conjunction with the University of Lincoln, explores how regenerative agriculture affects nutrient density. The researchers sampled a number of products and found that iron in kale could be up to 22 times higher in samples from regenerative farms compared with conventional ones, while selenium (an antioxidant) in dried peas was eight times higher and folate (good for red blood cells) in carrots was up to 20,000 times greater.
“Organic had to be our minimum baseline, because regen doesn’t have a certifiable standard. But while organic as a concept focuses on not doing harmful things, it doesn’t specify that you are doing positive things, Brkic says. Regenerative farms, in this case, were defined by those using cover crops and grazing animals, while abstaining from ploughing the land and using insecticides or other pesticides.
View image in fullscreen Fungicide and insecticide is sprayed on a field of bell pepper plants in Florida. Pics Inc/Alamy The way soil is treated by modern farming may be part of the problem. Ploughing and heavy use of chemicals – fertilisers, herbicides and pesticides – disturb and even destroy the soil’s mycorrhizal networks, which we are only just coming to understand but allow plants to pull in nutrients from the earth.
Dr David Montgomery, a US geologist and the co-author of the book What Your Food Ate, says regenerative agriculture is what we need to right the wrongs of the “degenerative” farming that helped sustain a postwar population boom, but wrecked soil health in the process. “It was the microbial truckers and miners in our soils that got put off the job by conventional agriculture, he says. “Regenerative practices that treat soil as an ecosystem can return those miners and truckers to the job. Montgomery and his wife, Anne Biklé, a biologist, undertook a study in 2022, albeit on a much smaller scale, noting some correlation between regenerative agriculture and higher nutrient density in food crops in the US.””””
Source: Guardian Science