Exploring healthy and climate-friendly diets for Danish adults: an optimization study using quadratic programming.

Area of Science:

• Dietary science
• Nutritional epidemiology
• Environmental science

Background:

• Healthy and sustainable diets are crucial for human and planetary health.
• Diets must balance nutritional needs, health outcomes, environmental impact, and consumer acceptance.
• The Danish plant-rich diet provides a benchmark for healthy and sustainable food-based dietary guidelines (FBDGs).

Purpose of the Study:

• To derive a nutritionally adequate and healthy diet for Danish adults.
• To minimize deviation from the average observed Danish diet.
• To achieve a 31% reduction in greenhouse gas emissions (GHGE), matching the Danish plant-rich diet's level.

Main Methods:

• Four diet optimization models were used via quadratic programming.
• Models incorporated constraints for nutrients, health targets, and GHGE.
• The objective function minimized deviation from the average Danish adult diet.

Main Results:

• Optimized diets achieved GHGE levels of 3.01–3.93 kg CO2-eq, compared to 4.37 kg CO2-eq in the observed diet.
• The proportion of energy from animal-based foods decreased from 34% (observed) to 21–25% (optimized).
• The optimized NutriHealthGHGE diet showed significantly less deviation (38%) from the average Danish diet than the Danish plant-rich diet (169%).

Conclusions:

• An optimized diet can be nutritionally adequate, healthy, and environmentally sustainable, aligning with climate-friendly FBDGs.
• This optimized diet offers an alternative that may be more acceptable to consumers.
• It can facilitate the population's transition towards healthier and more sustainable dietary patterns.