Leiden University recently published a meta-analysis combining data from dozens of international studies. These studies examined how crops respond when only the CO₂ content in the air increases, while soil, fertilisation, temperature and watering remain the same. The research received widespread attention, often with strong conclusions about declining nutritional value. For entrepreneurs in the food sector and companies in the meat sector, it is therefore important to put this research into perspective.
These controlled experiments showed that plants grow faster and produce more carbon-rich tissue under increased CO₂ levels. At the same time, they contain slightly less zinc, iron and protein per gram. The average decrease is around four per cent, with a number of crops responding more strongly. This is not a sign of soil depletion, but an internal plant mechanism: photosynthesis accelerates due to extra CO₂, while the uptake of minerals from the soil does not accelerate at the same rate. This results in a slight dilution of nutrients in the plant tissue. The research shows that this is a real physiological effect, but says nothing about actual nutritional changes in practice, because agricultural systems, cultivation methods, varieties and soils have a much greater influence than this CO₂ effect.
For the food sector, the most important question is whether this poses a risk to product quality or consumer health. Current scientific knowledge gives no reason to believe that this is the case. The declines are small, are largely offset in everyday agriculture by variations in soil quality and cultivation methods, and do not explain malnutrition or health problems in Europe. What the research mainly confirms is that growth and nutritional value do not automatically increase together. Those who work with bulk crops, basic raw materials or plant components may encounter variations in composition that are partly related to growth rate, but much more often to soil and cultivation conditions.
Animals obtain their nutrients from the land: from grass, herbs, roughage or mixed feed based on grains and soya. If plant-based feed contains slightly fewer micronutrients per kilogram, this can affect feed conversion, amino acid balance or mineral content in rations. This effect is small, but noticeable in intensive chains. At the same time, regenerative agricultural systems show that crops from living soils can actually be much richer in minerals, antioxidants and proteins. For animals, this means a more stable ration, better resistance and, ultimately, a more distinctive meat quality. Where regenerative cultivation is combined with local feed, herb-rich grassland and short chains, the result is a meat product that demonstrably outperforms meat produced on depleted soils or monocultures in terms of nutritional value, taste and composition. In that context, the CO₂ effect is virtually negligible; the soil determines almost everything.
For entrepreneurs in both plant and animal chains, the most important lesson is therefore not the CO₂ outcome itself, but the confirmation that nutritional value stems from the quality of cultivation. The Leiden research highlights how sensitive plants are to growth stimulants, but practice shows that soil health, diversity, regional cultivation and regenerative principles are the most important levers for stable and nutritious products.
The Leiden research demonstrates a clear physiological effect, but the practical impact in the food and meat sector is mainly determined by cultivation systems and soil quality. Both perspectives complement each other: science demonstrates the mechanism, while practice determines its actual significance.
Source: https://onlinelibrary.wiley.com/doi/epdf/10.1111/gcb.70568
