The importance of protein variety in a higher quality and lower environmental impact dietary pattern

Eating a variety of nutritious foods is fundamental to good nutrition. However, this principle is challenged when recommendations seeking to improve the environmental sustainability of diets call for avoidance of foods considered to have a higher environmental footprint, such as animal-sourced foods. Our objective was to assess the implications for nutritional adequacy of protein choice across Australian adult diets preselected as having higher quality and lower environmental impact scores.

Each individual diet was assessed for variety of food choice within the 'Fresh meat and alternatives' food group defined in the Australian Dietary Guidelines, which includes protein-rich foods such as eggs, nuts, tofu and legumes in addition to animal meats. Diets were grouped according to variety score and whether they included only animal meats, only alternatives or a variety of meat and alternatives. Nutrient content was assessed relative to estimated average requirements (EAR).

Australia.

1700 adults participating in the Australian Health Survey.

For diets with higher diet quality and lower environmental impact, the likelihood of achieving nutrient EAR significantly increased as variety of food choice in the 'Fresh meat and alternatives' food group increased (P < 0·001). Variety score and number of serves were also correlated (r = 0·52, P < 0·001) which is relevant since most diets did not meet the recommended minimum number of serves for this food group.

Greater variety within the 'Fresh meat and alternatives' food group is beneficial to meeting EAR and lower environmental impact diets can include three or more selections including foods of animal origin.