19 Jul Beyond the headlines about transforming diets
It is reasonably common to see headlines declaring the ability of the global food system to feed the global population purely from plant-sourced food. One recent article from Wageningen University & Research stated just that, and went on to demonstrate that sufficient protein is already produced from plants to meet global requirements. But we need more than just protein.
The conclusions reached in the article are supported by the DELTA Model®: if you remove all animal production and ignore bioavailability, there is more than enough protein to meet the needs of the global population.
However, “enough protein” here simply refers to total tonnes of protein in food compared to actual protein, or more importantly, amino acid requirements. If we instead consider bioavailable protein, then supply sits at around requirement – not much room for inequitable distribution of food. If we consider requirements of indispensable amino acids, the real nutrients within protein, we see around a 10% deficiency for lysine, rising to 30% upon consideration of bioavailability.
Perhaps more importantly, how does the picture look beyond protein? Protein and the amino acids are rarely the first limiting nutrients in the global food system. Under the scenario proposed by this article, the DELTA Model® predicts further global deficiencies for dietary fat, vitamins A, B2, B12 and E, calcium, and zinc. Iron and potassium supply would sit almost exactly at requirement, again leaving no room for overconsumption by any part of the population or inequitable distribution.
Headlines and claims such as these grab the attention, and likely convince many that such scenarios are sustainable. But the global food system and human nutrition are not so simple. Widespread dietary and food production change may indeed be required and have sustainability benefits, particularly in populations with consumption that does not reflect dietary guidelines. But these scenarios need to be informed by a holistic view of the food system and human nutrition.
