Nutrigenomics: Eating According to Your Genes

Would you believe it if I told you that 99.9% of all human DNA is identical?

You may wonder why all humans look different, have different personalities, and like other foods. Believe it or not, the 0.1% of DNA that varies between individuals is responsible for all the differences. Many of the differences are single nucleotide polymorphisms, or SNPs, essentially DNA mutations.

Depending on their location within the genome, these SNPs cannot affect health or cause a significant disease risk.

But does food–the introduction of external energy–affect our bodies and health?

Do these variances in our genome affect what foods we can eat? The science behind nutrigenomics says they do. This is why some people have food allergies and others don’t, and why some can have dairy and others can’t.

Let’s explore nutrigenomics and see how it can help our health.

What Is Nutrigenomics?

Nutrigenomics is the branch of science that aims to understand how food, nutrients, and compounds found in food impact gene behavior.

By better understanding these nutrient gene interactions, experts hope to prevent certain diseases and provide personalized nutrition advice based on an individual's genetic profile.

Nutrigenomics is a highly complex area of research, and many disciplines are involved in its study.

Nutrigenomics requires insight from nutrition, food science, biology, medicine, genomics, and public health to become better understood.

It’s an evolving science building immense momentum in the scientific community.

Three Core Concepts

The study of nutrigenomics is based on three core concepts:

-Individual genomes are different
-People vary greatly in nutrient availability and choices
-Nutritional deficiency and excess affect gene expressions and genome stability

The first is that each individual's inherited genome is different, and these differences influence nutrient metabolism.

Second, people vary significantly in nutrient availability and choices due to differences in culture, taste preference, socioeconomic status, and geographical location.

The third core concept is that nutritional deficiency and nutrient excess affect gene expression and genome stability.

Genome instability often results in mutations in the gene sequence or chromosomes, which can cause many adverse effects.

How what we eat and what’s best for us to eat is linked to our genes.

With these three pillars in mind, let's explore how what we eat is linked to our genes and their activity.

Research in the past decade has identified that genes determine our ability to metabolize nutrients.

This is because genes produce essential nutritional proteins, particularly digestive enzymes, which transport molecules that carry nutrients and co-factors that help enzymes do their jobs.

In turn, the nutrients we eat impact our genes' behavior and expression.

Mutations In Genes

As mentioned, mutations in these genes, or genome instability, can lead to many diseases and conditions, such as infertility, developmental defects, and cancer.

Oxidative stressors include DNA damage, such as tobacco smoke, strenuous exercise, and a high-fat diet–trans fats.

On the other hand, folate, antioxidant nutrients, and certain plant compounds enhance DNA repair and reduce damage.

Other diet-related factors influencing genome stability include diet composition, fiber content, food structure, antioxidant capacity, and gut microbiome composition.

Specific snips, or genetic variations, are known to influence nutrient requirements in susceptible individuals.

One example is a disease called phenylketonuria, or PKU.

In this condition, a genetic variation decreases the production of a particular enzyme needed to break down the amino acid phenylalanine.

Individuals with this genetic mutation can manage their condition by eliminating the amount of protein they eat.

Another example is celiac disease.

In this condition, exposure to gluten modifies the expression of specific genes, resulting in intestinal damage.

Lactose intolerance is a well-known condition that affects the gene that produces the lactase enzyme, resulting in inadequate production and an inability to digest lactose properly.

Goals

There are two overarching goals in the study of nutrigenomics:

-Prevention of disease
-Customization of therapy

Over time, diet has changed our internal human processes, leading to the onset of new diseases.

Nutrient gene interactions have been associated with metabolic stress, cardiovascular disease, diabetes, cancer, obesity, and irritable bowel disease.

It’s thought that using genome-protective nutrients in individuals with certain gene variances could prevent these significant diseases.

Nutrigenomic testing allows an individual to identify potential predisposed conditions and make dietary adjustments to help prevent their onset.

Customization of therapy in nutrigenomics means tailoring nutritional advice to an individual based on their genetic profile and specific gene variations.

People are genetically and metabolically different and respond differently to food and nutrients.

We also know that diet gene interactions have important health implications. Being able to identify a person's risk factors and recommend a dietary pattern accordingly could have significant beneficial effects.

Additionally, numerous studies have shown that people respond better to personalized advice that applies specifically to them, as opposed to one-size-fits-all recommendations.

Testing

How does nutrigenomic testing work?

Currently, testing is most commonly offered directly to consumers from commercial businesses. Most healthcare providers have yet to provide testing.

The actual process for consumers is simple and requires only a saliva sample obtained via a cheek swab.

The sample is then analyzed using advanced technology to identify genetic variants that modify the effects of dietary factors, increase disease risk, or influence food preferences.

Typically, only 30 to 50 genes are analyzed in a test based on their known functions.

The cost of nutrigenomic testing has varied drastically since genome sequencing became possible. The first genome sequencing took ten years of work and cost over a hundred million dollars.

In 2013, a complete sequence cost about $5,000, and in 2016, a robot could complete it in 24 hours for less than $1,000.

Today, several companies offer testing and interpretation of results for $300 to $500.

The BMM Takeaway

The study of nutrigenomics has yielded promising research in recent years.

However, more supporting evidence is needed before genetic testing becomes the basis for nutrition and dietary advice.

This is also the position of the Big Money Methods. Many studies conducted and published have only made weak associations due to limited resources or small study groups.

More extensive, controlled trials will create sound evidence linking nutrient intake to gene behavior.

Nutrigenomics is a young science with much room for growth and advancement, but it shows promising results.