Published on 15 July 2019
Explorer les fondements psychologiques des régimes alimentaires

The dietary choices of the French are currently in the limelight: there seems to be a trend towards a decreasing consumption of animal products and an increasing intake in plant proteins. It is key to look at that behaviour in a psychological light.

Eat at least five portions of fruit and vegetables a day, consume enough dairy products, avoid eating foods that are too fatty, too salty or too sweet… The recommendations made in France’s National Nutrition and Health Programme (PNNS), launched in 2001 by the Agency for Food, Environmental and Occupational Health and Safety (ANSES) and intended to improve the health of the French population by influencing their nutrition, now resonate like a familiar song. The statistics highlight the extent of the challenges faced: cardiovascular disease causes about 180,000 deaths a year in France, just ahead of cancer (150,000), obesity and diabetes concern respectively about 15% and 5% of the population, osteoporosis affects about 30% of women aged 50 and 50% of those aged over 60, and high cholesterol affects about one in five adults. The deep socio-economic changes that started in the 1950s prompted the French to change their lifestyles, diet and tastes. Products of animal origins and those with a high glycaemic index dominated in their plates, to the detriment of bread, cereals, potatoes and pulses.

However, today, that trend seems to be reversing. Over the last ten years, the meat consumption of French people has dropped by 12%. While vegetarians and vegans – for the most part, young people – still represent only 2.5% of the French population, more than a third of the population said they had adopted a “flexitarian” diet and significantly reduced their consumption of animal proteins.

Towards greener, healthier diets

We are currently experiencing an inverse evolution to that of the years following the Second World War,” confirmed Francois Mariotti, professor of nutrition at AgroParisTech, the Paris Institute of Technology for Life, Food and Environmental Sciences. “We are much more critical of meat consumption, given the rise of environmental concerns and issues regarding health and animal well-being. People are asking new questions: for instance, is it ethical to exploit animals so we can eat them?” The beginning of that inversion coincided with health crises such as the outbreak of mad cow disease and the loss of trust caused by the lack of traceability – not to mention the economic reason and the cost of meat. “As everything is converging, there is a good chance the downward trend will continue further.

While most French people do not plan to completely rule meat out of their diet, nutritionists are in agreement that plant-dominant diets are healthier. “The idea is to eat more vegetables and restore the balance between animal and plant proteins,” said Francois Mariotti. The new recommendations published by ANSES or Sante publique France, the national public health agency serving the French population, support that idea: less meat and more legumes, fruit, vegetables, wholegrain cereals, nuts… “From a scientific standpoint, we also think that eating large amounts of red meat heighten the risks of developing colorectal cancer or a cardiovascular disease, and we are quite certain for transformed meats such as cold cuts,” he added.

Questioning the French population’s dietary behaviour

Identifying the population groups that have risky diets and devising their psychological profile would make it possible to develop an appropriate communication inciting them to adopt a diet less damaging for their health. The Psychofood project, launched in 2017 with the support of MSH Paris-Saclay and initiated by Antoine Nebout, researcher for the Food and Social Sciences laboratory (ALISS) of France’s National Institute for Agricultural Research (IRNA), could be used for that purpose. The aim of this project, which involves behavioural economics and nutritional epidemiology, is to evaluate, within a single questionnaire, the diet of the French population and their attitude towards two fundamental psychological variables: risk and time. “By connecting these dimensions, we would be able to explain, with a currently unparalleled degree of precision, how these psychological variables affect the French population’s dietary behaviour,” commented Antoine Nebout.

Based on the questionnaire initially developed by the Generations and health team of the Centre for the epidemiology of mental and physical health (CESP–Inserm), this semi-quantitative food frequency questionnaire was reduced to 28 questions and addressed to the ELIPSS cohort study (Internet longitudinal study for social science). The cohort study is representative of the French population, gathering 3,000 participants equipped with tactile tablets and 4G subscriptions.

The first part of the questionnaire focused on respondents’ general dietary habits. It tackled all their meals, whether or not they were taken at home. Responders gave an average consumption (in days, weeks or months) of different foods throughout the previous twelve months. The second part tackled time preferences and respondents’ attitude to risk. “In the second part, using brief, hypothetical scenarios, we evaluate the importance given to luck and time in the event of monetary gains of varying amounts. Are respondents ready to take risks to obtain a higher amount than they could get straightaway, even if they don’t gain anything at all? Are they willing to wait a long time to gain a higher amount than they could have got straightaway?” Antoine Nebout explained. Two psychometric selfassessment questions using a Likert scale closed the questionnaire.

The collected data, which is currently being analysed, will shine a light on individuals’ socio-economic and demographic characteristics with regard to the psychological variables and diets observed. It will also give a very precise picture of the French population’s dietary behaviour in 2018.

The complete overhaul of our diet will involve an intellectual, psychological and cultural reassessment of the act of feeding ourselves,” Francois Mariotti predicted.



∙ Mariotti F. Editor. Vegetarian and plant-based diets in health and disease prevention. Elsevier, Academic Press. 2017.

∙ Workshop interdisciplinaire sur les déterminants psychologiques des comportements alimentaires du 10 mai 2019 :


Portrait: François Mariotti

“We know that plant-based diets are good for our health, the textbook example being the Mediterranean diet.ˮ 

François MariottiA graduate of the Paris-Grignon National Agricultural Institute (INA P-G), François Mariotti has a PhD in nutritional physiology and metabolism. He has been a lecturer and researcher at AgroParis- Tech since 2001. He has also presided ANSES’ panel of nutritional experts since 2012. Since 2015, he has headed a research team within the Nutritional Physiology and Feeding Behaviour research unit (AgroParisTech/INRA). Through their research, the team aims to understand the relations between the consumption of plant and animal proteins, nutritional security and cardiometabolic health.


Portrait: Antoine Nebout

"Understanding individual decisions and their biases to better address public health prevention issues."

A graduate of the National School of Statistics and Economic Administration, Antoine Nebout holds a master's degree in cognitive sciences and a doctorate in behavioural economics. He has been a researcher at INRA since 2013 and teaches behavioural health economics at AgroParisTech. At ALISS, he leads research projects to include behavioural questionnaires in large surveys and cohorts to explain individual health behaviours in terms of measured psychological traits and biases.


By Véronique Meder.

The original version of this article was published in L'Edition #10.