Barré Tangui, Perignon Marlène, Gazan Rozenn, Vieux Florent, Micard Valérie, Amiot Marie-Josèphe, Darmon Nicole
NORT, Aix-Marseille Univ, INSERM, INRA, Marseille, France.
MOISA, INRA, CIRAD, CIHEAM-IAMM, Montpellier SupAgro, Univ Montpellier, Montpellier, France.
PLoS One. 2018 Feb 14;13(2):e0191767. doi: 10.1371/journal.pone.0191767. eCollection 2018.
Reducing the consumption of meat and other animal-based products is widely advocated to improve the sustainability of diets in high-income countries. However, such reduction may impair nutritional adequacy, since the bioavailability of key nutrients is higher when they come from animal- vs plant-based foods. Meat reduction may also affect the balance between foods co-produced within the same animal production system.
The objective was to assess the impact of introducing nutrient bioavailability and co-production links considerations on the dietary changes needed - especially regarding meat ‒ to improve diet sustainability.
Diet optimization with linear and non-linear programming was used to design, for each gender, three modeled diets departing the least from the mean observed French diet (OBS) while reducing by at least 30% the diet-related environmental impacts (greenhouse gas emissions, eutrophication, acidification): i) in the nutrition-environment (NE) model, the fulfillment of recommended dietary allowances for all nutrients was imposed; ii) in the NE-bioavailability (NEB) model, nutritional adequacy was further ensured by accounting for iron, zinc, protein and provitamin A bioavailability; iii) in the NEB-co-production (NEB-CP) model, two links between co-produced animal foods (milk-beef and blood sausage-pork) were additionally included into the models by proportionally co-constraining their respective quantities. The price and environmental impacts of individual foods were assumed to be constant.
'Fruit and vegetables' and 'Starches' quantities increased in all modeled diets compared to OBS. In parallel, total meat and ruminant meat quantities decreased. Starting from 110g/d women's OBS diet (168g/d for men), total meat quantity decreased by 78%, 67% and 32% for women (68%, 66% and 62% for men) in NE, NEB and NEB-CP diets, respectively. Starting from 36g/d women's OBS diet (54g/d for men), ruminant meat quantity dropped severely by 84% and 87% in NE and NEB diets for women (80% and 78% for men), whereas it only decreased by 27% in NEB-CP diets (38% for men). The share of energy and proteins of animal origin was similar for the 3 modeled diets (approximately 1/5 of total energy, and 1/2 of protein) and lower than in OBS diet (approximately 1/3 of total energy, and 2/3 of protein).
Decreasing meat content was strictly needed to achieve more sustainable diets for French adults, but the reduction was less severe when nutrient bioavailability and co-production links were taken into account.
在高收入国家，为提高饮食的可持续性，人们广泛提倡减少肉类及其他动物性产品的消费。然而，这种减少可能会损害营养充足性，因为关键营养素来自动物性食物时的生物利用率高于植物性食物。减少肉类消费还可能影响同一动物生产系统内共同生产的食物之间的平衡。
评估引入营养生物利用率和共同生产联系因素对改善饮食可持续性所需的饮食变化（尤其是肉类方面）的影响。
采用线性和非线性规划进行饮食优化，为每个性别设计三种模拟饮食，这些饮食与观察到的法国平均饮食（OBS）差异最小，同时将与饮食相关的环境影响（温室气体排放、富营养化、酸化）降低至少30%：i）在营养-环境（NE）模型中，要求满足所有营养素的推荐膳食摄入量；ii）在NE-生物利用率（NEB）模型中，通过考虑铁、锌、蛋白质和视黄醇原A的生物利用率进一步确保营养充足性；iii）在NEB-共同生产（NEB-CP）模型中，通过按比例共同限制其各自数量，将共同生产的动物性食物（牛奶-牛肉和血肠-猪肉）之间的两种联系额外纳入模型。假设单个食物的价格和环境影响保持不变。
与OBS相比，所有模拟饮食中的“水果和蔬菜”以及“淀粉类食物”数量均增加。与此同时，肉类总量和反刍动物肉类数量减少。从女性每日110克（男性每日168克）的OBS饮食开始，在NE、NEB和NEB-CP饮食中，女性的肉类总量分别减少了78%、67%和32%（男性分别为68%、66%和62%）。从女性每日36克（男性每日54克）的OBS饮食开始，在NE和NEB饮食中，女性的反刍动物肉类数量大幅下降了84%和87%（男性分别为80%和78%），而在NEB-CP饮食中仅下降了27%（男性为38%）。三种模拟饮食中动物性来源的能量和蛋白质占比相似（约占总能量的1/5，蛋白质的1/2），且低于OBS饮食（约占总能量的1/3，蛋白质的2/3）。
对于法国成年人而言，要实现更可持续的饮食，严格需要减少肉类含量，但在考虑营养生物利用率和共同生产联系时，减少幅度较小。
