By Yunzhi Qian, PhD student in Nutrition
Have you ever wondered what is going on inside your body? If you could peek inside any cell in your body, you would be amazed by the numerous activities going on in the cellular hub. Whether you are eating dinner or walking your dog, awake or asleep, internal energy transformation never stops. The food we eat is the main source of energy for cellular activity, and cells use this energy for thousands of chemical reactions that keep our organs and body healthy.
Metabolism is a term used to describe all chemical reactions involved to support your body to maintain its living status and consists of two parts–anabolism and catabolism. Anabolism is the synthesis of complex compounds from simpler ones with the storage of energy, and catabolism is the breakdown of the molecule to get energy. For example, photosynthesis is an energy-requiring process that plants use the energy of sunlight to make sugar; on the contrary, cellular respiration is an energy-releasing pathway that cells break down sugar molecules. Chemical reactions usually happen in chains aka pathways, and the cells where all reactions happen use the nutrients you eat for energy.
Metabolomics is the comprehensive study of chemical processes involving metabolites, small molecule substrates, and products of cell metabolism. It is a powerful tool to use because metabolites can directly reflect the underlying biochemical activity happening inside our bodies. Current metabolomic technologies are capable of precise analyses of hundreds to thousands of metabolites in a biological specimen (blood, urine, fecal, etc). Metabolomics analysis can be categorized into two approaches, targeted and untargeted metabolomics. Targeted metabolomics is usually hypothesis-driven, it will validate and quantify a set of known metabolites that are in specific pathways. Conversely, untargeted metabolomics will collect, analyze, identify, and quantify all detectable metabolites in the sample, with the potential to form new scientific hypotheses. One of the biggest challenges faced by untargeted metabolomics is the identification of unknown compounds. Liquid chromatography-mass spectrometry (LC-MS) has enjoyed growing popularity as the platform for metabolomic studies due to its high throughput, soft ionization, and good coverage of metabolites. Metabolomics is a relatively young omics field that emerged in the late 20th century and has developed rapidly in the last 30 years.
The National Institutes of Health’s 2020-2030 strategic plan has set a primary goal for the field of precision nutrition to optimize metabolic response in individuals through tailored dietary approaches. Precision nutrition is a new term under the umbrella of precision medicine, it assumes that each individual may have a different response to specific nutrients, so that the best diet for one individual may be different than the best diet for another. Developing interventions to prevent or treat chronic diseases based on a person’s unique characteristics like DNA, race, gender, health history, and lifestyle habits is the main focus of precision nutrition. Metabolomics is a key enabler of precision nutrition, by identifying food-derived biomarkers, inter-individual variability in metabolizing the same foods in health and disease states. With the help of metabolomics, a personalized nutrition plan targeting an individual’s needs to optimize healthy outcomes will no longer be a dream.
Peer-edited by Juhi Chinthapatla, MSPH Candidate