It has long been investigated whether diseases are primarily attributed to an individual’s genetic code or are reflections of one’s nutrition. However, recent studies have shown that the two may not be as mutually exclusive as previously considered.
Especially with multidisciplinary studies, concepts that were once studied separately have now been found to be inherently linked. In this regard, DNA has been found to contain segments that respond to certain nutritional signals. This paved the way to a new branch of science that studies the effects of food on gene expression – nutrigenomics.
Nutrigenomics is a branch of science that studies the effects of dietary nutrients on gene expression or how the body reacts. Using tools for genetic analysis, nutrigenomics testing provides dieticians and nutritionists the necessary information for providing appropriate counsel with regards to the food they should eat to lead healthier lives.
On a simpler scale, nutrigenomics (or nutritional genomics) is defined as the study of the effects of food and food constituents on gene expression with the goal that the understanding of the relationships between the two can lead to dietary regimes towards better health.
A relatively new science, nutrigenomics is a product of decades of studies in different fields. One foundational basis of nutrigenomics is the understanding of the human genome.
The Human Genome Project was an international collaboration with the goal of sequencing and mapping out the human genome. It was a revolutionary accomplishment that took 13 years to finish. This accomplishment paved the way for countless other discoveries and advancements in human sciences. To this day, sequencing and analyzing the human genome can take mere days.
Once scientists were able to study and analyze human genomes, it was quickly found that the genetic code can include sections that can confer varying degrees of predisposition to certain diseases. However, people with such genes do not necessarily get the associated disease. This meant that there were other factors at play.
Hence, this is where nutrigenomics comes in. As a science, nutrigenomics investigates the relationships between nutrition, gene expression, and human health. This branch of science is an endeavor towards unveiling the root of human diseases via the classical debate of nature versus nurture. Once the science has become more established, it did not take long before private companies began offering nutrigenomics testing.
Privatized, commercial genetic testing is not a new concept. Various companies have offered genetic testing services with the goal of providing consumers with personal information. Some companies offer genetic testing services to provide heredity information.
Others offer genetic testing services to provide information on genetic markers that indicate a predisposition towards certain diseases. This is typically done by looking at certain genetic markers for health and analyzing for genetic mutations. Common mutations investigated include single nucleotide polymorphisms (SNPs) and inserts and deletions (INDELs).
Single nucleotide polymorphisms are mutations that change one nucleotide base for another. Since a gene is made of a sequence of a specific combination of four types of nucleotides (adenine: A, thymine: T, guanine: G, cytosine: C), a change in one base can have drastic effects.
On the other hand, a nucleotide or even an entire section of nucleotides can either be inserted or deleted due to various reasons. These changes can also have detrimental effects on a gene’s function.
Essentially, nutrigenomics becomes a tool for nutrition counseling. When a nutritionist has access to the genetic information of a patient, they can begin to provide necessary counsel regarding that patient’s diet while taking the genetic analysis into consideration. The genetic analysis provides the nutritionist vast amounts of data that a simple medical history cannot compete with.
With nutrigenomics data, the nutritionist can then begin to discuss dietary regimes specific to the individual. Testing can even be performed for cellular nutrition in order to identify genetic variations, lifestyle habits, or even blood micronutrient levels that are sub-optimal.
Another example of how a nutritionist can use nutrigenomics data is by suggesting a dietary regime that would help patients minimize the risk of certain diseases that their genes are encoded to have a predisposition for. If a patient’s DNA suggests a higher risk for coronary disease, then a dietary regime that can reduce the risk of that likelihood from happening will be suggested.
Genetic information holds limitless amounts of information that a dietician or a nutritionist can use to help people live healthier lives. Nutrigenomics data can also be used to determine if people have certain tendencies that can be adjusted for. The data can show that some people are less efficient in absorbing certain vitamins or minerals so the nutritionist can then suggest an increased intake of such nutrients.
One big area of nutrigenomics study is cancer prevention. The concepts that intertwine nutrigenomics and cancer prevention stem from numerous studies showing that dietary factors are highly involved with cancer development. While diet and cancer development can be attributed to certain dietary mutagens (i.e., substances that can induce mutations), diet and cancer are also linked by how diet is associated with DNA health – a notion wherein cancer develops from mutated cells due to erroneous DNA metabolism.
Nutrigenomics can be an incredible tool for disease risk diagnosis and prevention. However, there are certain reasons why the science of nutrigenomics still has a long way to go.
Firstly, the science of nutrigenomics is indeed a positive step towards multidisciplinary and personalized medicine since it allows dieticians and nutritionists to use genetic information as a basis for medical advice. However, there are still more steps needed to be taken when discussing multidisciplinary approaches – especially when it comes to health.
While diet is indeed a major factor, nutrigenomics looks at health without addressing other key factors such as lifestyle, health history, health status, cultural identity, personal preferences, the willingness of the patients to change, and even their own health goals.
Another problem with nutrigenomics is that it has become commodified quite quickly through direct-to-consumer genetic testing companies. As a way to streamline operations, it is understandable to process genetic data through simple categorization.
For example, a mutation in a certain gene will mean a certain explanation. However, genetic analysis can be more complicated than that. Skilled genetic analysts would sometimes have to look at multiple genes and additional factors to reach a single conclusion.
2. Floris M, Cano A, Porru L, et al. Direct-to-Consumer Nutrigenetics Testing: An Overview. Nutrients. 2020;12(2):566. Published 2020 Feb 21. doi:10.3390/nu12020566
3. Nasir A, Bullo MMH, Ahmed Z, et al. Nutrigenomics: Epigenetics and cancer prevention: A comprehensive review. Crit Rev Food Sci Nutr. 2020;60(8):1375-1387. doi:10.1080/10408398.2019.1571480