title: How low can dietary greenhouse gas emissions be reduced without impairing nutritional adequacy, affordability and acceptability of the diet? A modelling study to guide sustainable food choices.
abstract: To assess the compatibility between reduction of diet-related greenhouse gas emissions (GHGE) and nutritional adequacy, acceptability and affordability dimensions of diet sustainability.
  
  
  
  Dietary intake, nutritional composition, GHGE and prices were combined for 402 foods selected among those most consumed by participants of the Individual National Study on Food Consumption. Linear programming was used to model diets with stepwise GHGE reductions, minimized departure from observed diet and three scenarios of nutritional constraints: none (FREE), on macronutrients (MACRO) and for all nutrient recommendations (ADEQ). Nutritional quality was assessed using the mean adequacy ratio (MAR) and solid energy density (SED).
  
  
  
  France.
  
  
  
  Adults (n 1899).
  
  
  
  In FREE and MACRO scenarios, imposing up to 30 % GHGE reduction did not affect the MAR, SED and food group pattern of the observed diet, but required substitutions within food groups; higher GHGE reductions decreased diet cost, but also nutritional quality, even with constraints on macronutrients. Imposing all nutritional recommendations (ADEQ) increased the fruits and vegetables quantity, reduced SED and slightly increased diet cost without additional modifications induced by the GHGE constraint up to 30 % reduction; higher GHGE reductions decreased diet cost but required non-trivial dietary shifts from the observed diet. Not all the nutritional recommendations could be met for GHGE reductions ≥70 %.
  
  
  
  Moderate GHGE reductions (≤30 %) were compatible with nutritional adequacy and affordability without adding major food group shifts to those induced by nutritional recommendations. Higher GHGE reductions either impaired nutritional quality, even when macronutrient recommendations were imposed, or required non-trivial dietary shifts compromising acceptability to reach nutritional adequacy.
authors.affiliation: 1NORT, Aix-Marseille Université,INRA,INSERM, Faculté de Médecine de la Timone,27 Boulevard Jean Moulin,13005 Marseille,France.
authors.forename: Marlène
authors.initials: M
authors.lastname: Perignon
authors.affiliation: 1NORT, Aix-Marseille Université,INRA,INSERM, Faculté de Médecine de la Timone,27 Boulevard Jean Moulin,13005 Marseille,France.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Masset
authors.affiliation: 1NORT, Aix-Marseille Université,INRA,INSERM, Faculté de Médecine de la Timone,27 Boulevard Jean Moulin,13005 Marseille,France.
authors.forename: Gaël
authors.initials: G
authors.lastname: Ferrari
authors.affiliation: 1NORT, Aix-Marseille Université,INRA,INSERM, Faculté de Médecine de la Timone,27 Boulevard Jean Moulin,13005 Marseille,France.
authors.forename: Tangui
authors.initials: T
authors.lastname: Barré
authors.affiliation: 2MS-Nutrition,Marseille,France.
authors.forename: Florent
authors.initials: F
authors.lastname: Vieux
authors.affiliation: 2MS-Nutrition,Marseille,France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Maillot
authors.affiliation: 1NORT, Aix-Marseille Université,INRA,INSERM, Faculté de Médecine de la Timone,27 Boulevard Jean Moulin,13005 Marseille,France.
authors.forename: Marie-Josèphe
authors.initials: MJ
authors.lastname: Amiot
authors.affiliation: 1NORT, Aix-Marseille Université,INRA,INSERM, Faculté de Médecine de la Timone,27 Boulevard Jean Moulin,13005 Marseille,France.
authors.forename: Nicole
authors.initials: N
authors.lastname: Darmon
mesh_terms: D003247:Conservation of Natural Resources; D004032:Diet; D002149:Energy Intake; D005523:Food Supply; D005602:France; D017752:Greenhouse Effect; D000074382:Greenhouse Gases; D006801:Humans; D018673:Nutrition Policy; D009753:Nutritive Value
chemical_list: D000074382:Greenhouse Gases
keywords: Affordability; Cultural acceptability; Diet cost; Diet sustainability; Diet-related greenhouse gas emissions; Dietary changes; Food choices; Food consumption; Linear programming modelling; Nutritional quality