Science closer to prescribing nutrients to fight disease

We all know maintaining a healthy diet is more than just counting calories. While eating the right amount of food is important to avoid gaining too much weight, the types of food you choose to fuel your body is even more critical.

You are what you eat. This saying has been around in some form or other since the 1800s, way before people were so mindful of what they put into their bodies. The Greek physician Hippocrates, who wrote the Hippocratic oath still used by doctors today, is credited with the phrase: “Let food be thy medicine and medicine be thy food.”

Experts have known — intuitively, even if not quite definitively — that what we eat and drink has direct and significant effects on our overall health. This belief led to the development of the science of nutrition, which studies the nutrients in our food; how our body uses these nutrients; and the relationship among diet, health and disease.

In the late 19th century, genetics — the study of genes, genetic variation and heredity — was introduced. The pinnacle project of this field was the Human Genome Project (HGP), an international scientific research endeavor that remains the world’s largest collaborative biological study. Launched in 1990 and completed on April 14, 2003, the goal of this research program was the complete mapping and understanding of all human genes.

It might help simplify things to think of the gene map as the basic set of inheritable instructions for the development and function of each individual. It’s what makes you, you.

After the conclusion of this study, however, new insights and questions about the influence of nutrients arose, including:

Will gene expression in response to metabolic processes influence health?

Are gene expression and metabolic response the result of the interaction among genotype, environment and nutrients?

Could understanding how this interaction occurs between genes and nutrients lead to the prescription of specific diets for each individual?

To answer these and other questions, a new branch of science call nutritional genomics was introduced. Nutritional genomics, more commonly referred to as nutrigenomics, is heralded as having the potential to be the next big thing in the fight against lifestyle-linked diseases.

While nutrition focuses on the nutrients that enter our system and their general effects on our body and genetics on how our genetic makeup could lead to specific traits, nutrigenomics combines the two to study how nutrients modulate or vary gene expression and ultimately influence how cells, metabolism and the organism function as a whole. In simple terms, nutrigenomics helps us understand how what we eat and drink interact with our specific genetic composition and what that means for our health.

Let’s take diets, for example. While one type of diet might work for some or even many, it might not necessarily work for you. Since no two humans are genetically identical, the nutrients you get from that particular diet will interact differently with your genes. That could lead to unintended results.

Understanding how an individual’s genetic makeup responds to a particular nutrient provides new opportunities to incorporate natural bioactive compounds into food for a specific group of people with a similar genotype. This is especially applicable to such lifestyle-associated diseases as cardiovascular conditions and diabetes.

Nutrigenomics offers the potential to create personalized, genotype-based nutrition to mitigate risk factors for different individuals or a specific population.

Several tools are used in nutrigenomics to identify disease risk factors and progression:

Food diaries to record nutrient input.

Such biomarkers as metabolite or hormone levels to understand a body’s response.

Genomic assays to identify relevant gene variants.

Such clinical data as age, weight, sex and body mass index to monitor the effects of food.

Although we’ve only scratched the surface when it comes to nutrigenomics, learning about its potential gives us the direction and initiative necessary to expedite advancements in the field. Pretty soon, doctors might provide each one of us with more precise nutrient recommendations for our specific genetic makeup, down to the last gram.