Biodiverse landscapes, biodiverse plates: lessons from Ucayali and Colombia's new dietary guidelines
WHO describes four core principles of a healthy diet: adequacy, balance, moderation, and diversity. Diversity is defined as "inclusion of a wide variety of nutritious foods within and across food groups" (WHO healthy diet fact sheet). The word "within" is often easy to overlook.
- Amazon biome
- Colombia
- healthy diets
- biodiversity
- food environment
Diversity is one of four pillars, but we usually measure only half of it
WHO describes four core principles of a healthy diet: adequacy, balance, moderation, and diversity. Diversity is defined as "inclusion of a wide variety of nutritious foods within and across food groups" (WHO healthy diet fact sheet). The word "within" is often easy to overlook.
Most of us in the field (me included) have been trained to measure diversity between food groups. Indicators like the Household Dietary Diversity Score (HDDS) or Minimum Dietary Diversity for Women (MDD-W) ask: did you eat some fruit, a vegetable, or a fish yesterday? One banana counts the same as five native Amazonian fruits.
Between and within diversity: why the second half matters
Diversity between food groups tells us if the diet covers the basics. Diversity within food groups tells us how many different species and varieties sit behind those basics. Different species carry different micronutrients, fibers, and bioactive compounds, so two different "fruit" servings are not nutritionally the same. The diversity principle teaches us that the more diverse we eat, the more chances we have to cover all our needs in terms of nutrients and health-protective compounds.
The evidence for counting species has grown considerably in recent years. Hanley-Cook, Lachat and colleagues compared several food biodiversity metrics across cohorts in nine European countries and five low- and middle-income countries (Nature Food, 2025). The simplest one, dietary species richness (DSR), which is just the count of distinct species a person eats, captured the biggest differences between and within countries. Higher DSR was associated with nutrient adequacy in LMICs and with lower mortality in Europe.
A follow-up in the European EPIC cohort found that plant species richness also went hand in hand with lower greenhouse gas emissions and land use (Berden et al., Nature Food, 2025). Counting species is therefore not only about nutrition. It links what people eat to the landscapes that feed them.