Covered market at Brive la Gaillarde. © INRA, Bertrand NICOLAS

Towards more sustainable food supplies

Throwing new light on controversial issues

In the context of duALIne, new views emerged concerning certain more or less controversial issues.  Among others, it seems that a nutritionally satisfying diet including high levels of fruits and vegetables has an impact that is equivalent to, if not greater than, that of a diet rich in animal products, despite commonly-held views on the negative impacts of meat consumption.

Updated on 02/22/2013
Published on 12/17/2012

Meat © BOSSENNEC Jean-Marie
Meat © BOSSENNEC Jean-Marie
Food systems and greenhouse gases

The link between a diet containing high levels of animal products and greenhouse gas (GG) emissions is not a simple affair.  These products certainly emit more GG per kilogram than plant-based foods such as starches, fruits and vegetables.  However, plant-based diets, which are nutritionally the most adequate, are consumed in such quantities that they are ultimately associated with equally high (in men) or even higher (women) GG emissions than nutritionally poor diets which contain more meat.  This was demonstrated by a study performed for duALIne and funded jointly by ADEME and INRA, which examined and ranked the self-selected diets of French people according to their alignment with nutritional guidelines.

So, finally, there are few differences in carbon impact between meat-based and more plant-based diets, the latter being more beneficial in terms of its nutritional value.

Mean carbon impact as a function of groups of nutritional quality and gender (g eqCO2/day).. © inra
Mean carbon impact as a function of groups of nutritional quality and gender (g eqCO2/day). © inra

Men : Non-significant differences in impacts between diets

Women : Impact ("adequate" diets) > impact ("inadequate" diets)

A reduction in carbon impact might be better achieved by reducing the total quantities ingested than by modifying the composition of diets. If this observation is confirmed by more detailed studies, it raises the question of the conditions and feasibility of an economic model that favours limiting the quantities consumed: how far are economic actors in the agri-food sector, and consumers, prepared to accept such changes, under what conditions and at which time horizon ?

Upstream versus downstream food sectors

DuALIne demonstrated the value of specifically studying downstream agri-food sectors – while still bearing in mind the need to integrate upstream activities; i.e. agricultural production.  However, it is still necessary to develop knowledge on the downstream aspects of this chain.  GG emissions are evaluated less efficiently downstream of farms than upstream, even though they are at least as important.  Similarly, the concept of agro-ecology which is developing at the production level has little equivalence in the downstream agri-food system, the use (or production) of ecosystem services at the agri-food transformation/distribution stage beinga priorilimited.  The scientific landscape concerning downstream aspects is piecemeal and scanty, probably because it involves numerous communities with disciplines that are more varied than those linked to agriculture.

Vieux, F., Darmon, N., Touazi, D. and Soler, L.G., 2012. Greenhouse gas emissions of self-selected individual diets in France : Changing the Q23 diet structure or consuming less ? Ecological Economics, 75 : 91-101.
Available at : http://dx.doi.org/10.1016/j.ecolecon.2012.01.003.

Vieux, F.,Soler, L.G., Touazi, D. and Darmon, N., 2013. High nutritional quality is not associated with low greenhouse gas emissions in self-selected diets of French adults. Am J Clin Nutr (in press).