Grant: CIHR Fellowship

Diet remains an important contributor to heart disease and diabetes prevention in Canada and globally. The evidence to support specific dietary strategies is limited, and current dietary advice relies largely on evidence from small randomized controlled trials (RCTs) of risk factors, and prospective cohort studies that are based on self-reported diet and cannot provide cause-and-effect relationships. Innovative nutrition research is needed that can replace the evidence from traditional large clinical outcomes trials at a much lower cost. Metabolomics is an emerging field in nutrition and chronic disease epidemiology. This approach uses the products of overall metabolism to develop an objective metabolic signature for a dietary pattern, which is not subject to the same measurement and reporting errors of traditional self-report dietary tools. This approach can also be used to produce an inferred genetic signature for Mendelian randomization, which allows for the assessment of causal relations. Through this project, I will work with the Portfolio Diet, a plant-based dietary portfolio of cholesterol-lowering foods (nuts, plant-protein, sticky fibre, plant sterols, and heart-healthy oils), to include this new transformative approach. The primary aim of this project is to determine a metabolic signature of the Portfolio Diet from past and ongoing RCTs of the diet. The secondary objective is to apply and compare this metabolic signature to 3 large U.S. cohorts (the Nurses' Health Study and Health Professional Follow-up Study) and assess the relation of the Portfolio Diet, its metabolic signature, and inferred genetic signature with heart disease and diabetes. This approach will be an innovative technique that will advance the field of nutrition epidemiology. Heart disease and diabetes are very common in Canada and worldwide, therefore, research like this project that aims to identify dietary patterns to prevent these diseases could impact millions of people.