Foodomics: Work in Progress
How can analysis of food products be used to optimize their health and nutritional benefits?
Peter Zahradka |
Most people are familiar with the adage “you are what you eat.” For the general public, this concept would typically be associated with the various food groups that are used to help promote good eating habits. But none of the foods consumed consist of just a single item. Rather, everything we eat is a complex mixture of thousands of different compounds. Though the initial focus of food research was to understand how the nutrients contained in food contributed to health, over time it has been recognized that even the very minor constituents present in our foods may be capable of affecting our health. As a result, identifying which ones can be used for this purpose has become of great interest.
A century ago, food chemists spent years isolating and characterizing single molecules to determine their role in human nutrition. Considerable progress has been made since then in profiling the compounds present in our food, something that has become possible through the development of analytical methods and equipment with ever greater sensitivity and speed. It is now possible in just a few days to prepare an extensive list of the compounds present in a single food sample and compare that list to others obtained from samples via other sources. These achievements have gone hand-in-hand with the increases in computing power that now make it possible to quickly identify many of the compounds detected with our analytical instruments. However, whether certain compounds produce health benefits cannot be determined by these approaches, and our ability to establish the biological significance of individual compounds has not expanded at anywhere close to the same rate as our analytical capabilities. We must now ask ourselves if this limitation needs to be addressed.
A PubMed search using the term “metabolomic” now produces almost 14,000 results. The earliest papers using this term were published in 2000, and 2015 had over 2,000 papers on this topic. The bulk of these papers provide lists of compounds detected in certain samples, and a large number looked at associations between the intervention or manipulation used on the system and the metabolite profile. In a number of instances, the profile was examined for potential use as a predictive marker or diagnostic in relation to the biological condition under investigation. In rare instances, papers were trying to determine whether certain compounds identified during profiling would serve as biomarkers. The latter approach has been assisted in large part through the ability to interrogate large biochemical pathway and disease databases. At the same time, determination of a causal relationship requires perturbation of the system with the compound of interest, an approach that requires a workable dose.
Analytical chemistry is certainly moving in the direction of detecting ever smaller amounts of these compounds, but determination of biological effect needs large amounts of pure compound. Unfortunately, extraction and purification methodology has not changed much over the past few decades, although computer automation of these systems has helped to improve consistency and speed. A similar scenario occurred in the period from 1970 to 2000, when the ability to rapidly clone individual genes became possible, but the ability to define their biological function was time consuming. However, it is worth noting that the most significant publications were those that established the contribution of the gene to a biological system. Unfortunately, the current situation is a much more difficult one, since unlike genes, not all of the compounds present in a food will have a biological effect. Given this state of affairs, it is quickly becoming imperative that closer ties must develop between analytical chemists and researchers in the biological sciences to bridge the huge gap that is forming. It is only through better connections between these disciplines that it will be possible to develop a comprehensive understanding of how the foods we eat or the compounds they contain can be used to benefit our health.
Zahradka graduated with a PhD in Biochemistry from the University of Western Ontario (London, Ontario) and subsequently obtained post-doctoral training at both Stanford University and the University of Guelph before joining the Department of Physiology, University of Manitoba, in 1991. His laboratory is located at the St. Boniface Research Centre. He was a member of the Institute of Cardiovascular Sciences and his work on vascular disease identified a novel pharmaceutical compound capable of preventing restenosis. From 2006 to2013 he served as the Director of the Canadian Centre for Agri-Food Research in Health and Medicine (CCARM) and became CCARM Deputy Director in 2016. He also is head (since 2012) of the Division of Endocrinology and Metabolic Disease, Department of Physiology and Pathophysiology. Dr. Zahradka’s lab is engaged in studying novel bioactive compounds from buckwheat and pulses (lentils/beans) in relation to the management of diabetes, obesity and vascular disease. He has worked closely with Dr. Carla Taylor since 2000 and together they have developed a clinical trial program to validate the results of their animal and cell culture studies and thus translate this research to benefit human health.
