Full4Health: Understanding Food-gut-brain Axis Across the Lifecourse

Participants (male and female, lean and obese, children, teenagers, adults, and elderly) will take part in 4 morning sessions, consuming a test breakfast milk based beverage and appetite. Biomarkers in blood will be measured and behavioural questionnaires completed. We will also collect a single saliva sample from each participant to examine genetic traits related to appetite, food choice, body weight, and energy expenditure. There will be two milk based beverages, one protein enriched (30% protein from calories) and one normal protein (15% protein). Participants will be offered a morning snack buffet to assess ad libitum energy intake. Phase 1 will also include a subgroup of malnourished male and female elderly participants. However, this group will only complete two morning sessions during which they will consume a low protein and a high protein milk based beverage. Appetite will be recorded and libitum energy intake will be measured. In addition, 24hr energy intake will be recorded.

We will fMRI scan normal weight and overweight subjects of both gender from the four different age groups only: 8-10, 13-17, 24-45 and 65-75 years. Participants will be measured twice, on separate days, either after an overnight fast or after a test meal, fed to satiation (because hunger will modulate the response to food presentation). The participants will conduct a computerised task that will be performed in the scanner to assess hedonic responses to food cues. Physiological biomarkers will be measured during both trials for the assessment of appetite hormone circulation. Saliva samples will be taken for DNA analysis. DNA extraction techniques will be used to examine genetic traits linked to appetite, food choice, body weight, and energy expenditure.