Personalised diet for healthier longevity: the role of dietary changes, sensitive windows of exposure, and psychosocial background

Research problem and specific questions: dietary recommendations considering older adults’ needs can contribute to healthier, longer lives, but evidence from context-specific, large-scale studies is limited.

We will leverage Swedish multicohort data to answer three research questions: 1) Which dietary recommendations could have the highest impact on healthy longevity?, 2) What is the most sensitive window of exposure to said foods and how long are the latency periods?, and 3) How are the benefits from dietary recommendations influenced by older adults’ psychosocial background?Data and method: we will use data from 5 cohorts belonging to the NEAR research infrastructure: SNAC-K, SNAC-N, SNAC-S, H70, and SMCC, and replicate the analyses in datasets from Spain and the United Kingdom (n=25,500).

Data will be harmonised by NEAR and processed by the applicant, who has a proven track record in multicohort analyses. Dietary variables will mirror the 14 food groups from the Swedish Food Agency guidelines.

Healthy longevity will be operationalised as time to death or poor health as per the Health Assessment Tool (i.e., a composite score of physical and cognitive function, chronic diseases, and disability), and analytical techniques will include substitution models simulating food replacements, interactions with age and exposure lagging, and factorial designs combining socioeconomic status and social network.Societal relevance and utilisation: suboptimal diet in Swedish older adults accounts for 13,400 deaths per year and 187,000 disability-adjusted life-years.

The ultimate goal of the project is to contribute to the personalisation of the Swedish dietary guidelines to the needs of older adults.

Project results will be disseminated through 3 scientific publications, congress communications, a magazine for older adults, and workshops at the Swedish Food Agency.Plan for project realisation: necessary data have been collected and are available for request and processing.

The project plan has been approved by the supporting research team and will be implemented over a period of 3-years with minimal overlaps between study aims (i.e., 13 months for data management and 10, 8, and 7 months for aims one, two, and three).

The budget will correspond largely to the salary of the applicant, that of a research assistant, and running costs, as salaries of other participants are covered by their respective organisations.