Micronutrients and human appetite: Investigating the hidden drivers of food selection

Some animals can sense when they’re missing important nutrients and change their eating habits to fix these imbalances. This idea is called ‘nutritional wisdom’. While research from nearly a century ago showed that human infants might also have this ability, scientists haven’t done much to explore it further.

Recent studies have suggested that adults may prefer food combinations that offer a wide variety of vitamins and minerals (called micronutrients). These choices seem to go beyond just eating randomly or for taste.

As well as influencing whether a food is chosen, there is growing interest in whether a food’s micronutrient content may affect how much of it we eat. For example, do we eat larger portions of foods that are lower in micronutrients in an effort to get the nutrients our bodies need?

Project aims

This PhD project aims to explore whether people choose and eat foods based on how rich they are in micronutrients. It will look at both the types and amounts of food people eat, and how that relates to:

• The total amount of micronutrients in the food
• Micronutrient density (how many nutrients per calorie)
• Micronutrient complementarity (variety of different nutrients in the food)

The project will ask 3 key questions:

1. Do people who menstruate, especially those with heavy periods (who are more likely to have low iron levels), choose more iron-rich foods when their iron levels are lower?
2. Do children eat more fruits and vegetables that are higher in micronutrients? And is this linked to fussy eating habits and lower nutrient intake?
3. In people with nutrient absorption issues (like coeliac disease or after weight-loss surgery), do food preferences change before and after diagnosis or surgery?

What we hope to achieve

This research could help us better understand the role of micronutrients in food choices and how our bodies might guide us to eat what we need.