A Guide to Nutrigenomics Testing: First Steps Towards Personalized Nutrition

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Jules Walters • Jan 12, 2024

Are you wondering how your genes affect what you should eat? Nutrigenomics testing opens the door to personalized nutrition by analyzing your DNA to guide your diet choices. This innovative approach offers insights into how genetic variations influence your response to different foods and nutrients. In this guide, we’ll explore how nutrigenomics testing works, what it can reveal about your health, and how you can use this information for health and well-being.

Key takeaways

  • Nutrigenomics testing offers personalized dietary recommendations based on your genetic profile, potentially enhancing health by tailoring diet according to your genetic response to certain foods, including food intolerances and sensitivities.
  • Types of nutrigenomic tests vary, from single variant analysis to complete genome sequencing, all aimed at guiding personalized nutrition to help with weight management and overall health.
  • Interpreting nutrigenomic test results requires the expertise of healthcare professionals who can provide personalized dietary recommendations, and make the most of the genetic information.

Understanding nutrigenomics testing

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Nutrigenomics testing is a remarkable breakthrough in the field of personalized nutrition. It involves an analysis of the interaction between your genes and nutrition, offering personalized dietary recommendations based on your genetic profile. This science brings together two crucial aspects of human well-being: genetics and nutrition.

Nutrigenomics has the potential to help in weight management, enhance metabolism, and explain bloating after a meal. Maybe you’re sensitive to gluten? In essence, nutrigenomics is the key to unlocking your body’s full potential and achieving your health goals through well-informed dietary decisions.

The science behind nutrigenomics

Unpacking the science behind nutrigenomics takes us to the molecular level. Nutrigenomics is the study of how our diet influences the molecules within our body, such as genes, proteins, and metabolites.

Our genes are like the instruction manual for our body, with a copy of our personal genetic manual in just about every cell of our body. We can’t change what’s written in our personal instruction manual. We’ve inherited that from our parents. But we can influence what’s called genetic expression: when our genes are turned on and off, and how much protein they tell our bodies to make when the genes are turned on.

The science of nutrigenomics is relatively new. It started appearing in science journals in the early 2000s. The field was powered by the completion of the Human Genome Project, which described the estimated 20,000 to 25,000 human genes back in the 1990s.  

Since then, much more research has gone into understanding how the different foods we eat interact with our genes.

The principles underlying nutrigenomics acknowledge that:

  • Common dietary chemicals interact with our genes
  • Genetic predisposition determines our body’s response to diet and the impact of diet on gene expression
  • What you eat does not only provide you with energy and essential nutrients. It also interacts with your DNA, impacting your health on a genetic level

Genetic variants and their impact on nutrition

Genetic variation, sometimes referred to as genetic differences, has significant implications for our nutrition; impacting nutrient absorption, metabolism, and food intolerances. My DNA will be different from yours, and perhaps in significant places, through multiple genetic variants. The 1000 Genomes Project, completed in 2015 as an international effort to understand human genetic variation, found over 88 million genetic variations between us.

Out of the vast majority of variations, about 99% are rare, but the average person can have five million small variations in their genes. These are called single nucleotide polymorphisms, or SNPs for short, pronounced snips. Nutrigenomic testing looks at how these genetic variants are affected by our environment, particularly by what we eat.

Nutrigenomic testing can identify genetically-linked food intolerances and sensitivities, such as lactose and glucose intolerance and caffeine sensitivity.

These findings can lead to personalized dietary changes. For example, a slower caffeine metabolizer might limit their caffeine intake to one or two cups a day, and only in the morning. That way, they can ensure the caffeine’s worked its way through their body before it’s time to sleep.

Types of nutrigenomic tests

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There are various types of nutrigenomic testing available. Recently, I appreciated the comprehensive results from 3x4Genetics, which delivered a 30-page report on my genes from a cheek swab I sent in the post. DNA is a stable molecule, so it’s possible to send your DNA in the post. No need for a blood draw.

3x4Genetics analyzes groups of genetic variants across 36 metabolic pathways to give you a personal account of how your genes are impacted by the food you eat. It also reports on the exercise you take and your response to stress. I learned that I’m gluten sensitive, which was news to me, so I have started a 30-day experiment to eliminate gluten – and I’m certainly feeling lighter already!

The metabolic pathways covered by 3x4Genetics include genetic variations associated with:

  • Mood and behavior
  • Memory and brain health
  • Histamine overload
  • Hormone balance
  • Glucose and insulin
  • Cholesterol
  • Bone health

Other providers of nutrigenomic and genetic testing include Nutrigenomix, as well as 23andme. 23andme will give you some insights on how your genes are affected by foods, but not as much as specialist nutrigenomics testing providers.

Interpreting your nutrigenomic test results

While nutrigenomic testing has the power to revolutionize your diet and health, the interpretation of the test results can be complex. I have a degree in molecular genetics and nutritional training through the Institute for Integrative Nutrition, which I found hugely helpful in interpreting the results. If you order a nutrigenomics test, I highly recommend the expertise of healthcare professionals, particularly a nutritionist or dietitian specialized in nutrigenomics, to take you through the findings. They can help you develop a personalized health plan that includes food, exercise, nutrition and supplements.

3×4 Genetics has a helpful practitioner locator on their website. The Institute for Functional Medicine also has a Find A Practitioner tool on their website. Functional medicine doctors look for the underlying causes of a condition, rather than just treat the symptoms. Food intolerance is one of the checks a functional medicine doctor usually includes.

Nutrigenomics tests offer valuable information about genetic and environmental factors that can help you make informed decisions about your health and well-being.

Personalized nutrition recommendations

Armed with the knowledge of your unique genetic information, you can receive personalized nutrition recommendations that are tailored to your needs. These variations can have an impact on how your body responds to:

For instance, if you have specific genetic variants, a nutritionist might recommend:

  • Incorporating additional omega-3 fatty acids to reduce inflammation
  • Adding more foods that are high in anti-oxidants, like blueberries and dark chocolate
  • Supplementing with vitamins if your ability to absorb particular vitamins is reduced

Benefits of nutrigenomics testing for health outcomes

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Nutrigenomics testing holds significant potential to improve health outcomes. It can play a significant role in promoting a long and healthy life, by identifying genetic traits that contribute to food intolerances and weight gain.

Nutrigenomics testing also helps design a personalized diet and exercise plan.

Imagine knowing precisely what your body needs, what it doesn’t, and how it responds to various nutrients. This is the promise of nutrigenomics: a future where diet is no longer a one-size-fits-all model, but a personalized approach designed to optimize your health, based on your unique genetic profile.

Limitations and considerations

Despite the promise of nutrigenomics testing, awareness of its limitations is important. Nutritional genomics tests what’s called low-penetrance genes. That means some people have a genetic variation but show no or little effect.

My response to gluten is a good example of this. I’ve eaten gluten in bread and pasta for decades: in fact, bread and pasts are two of my favorite foods. However, it seems genetically my body would prefer that I lived without them. I have a variation at a gene called HLA, the same variation common in people with celiac disease, which is triggered by gluten. So, now I’m seeing what life would be like if I eliminated gluten.

High-penetrance genes mean: if you have the genetic variation, you have the condition. Many single gene disorders, like cystic fibrosis and sickle cell disease, are highly penetrant.

For low-penetrant genes, lifestyle choices – particularly diet and nutrient intake – can affect genetic expression. As the saying goes for nutrigenomics, genetics loads the gun but lifestyle pulls the trigger.

Environmental factors and lifestyle choices

Our environment and lifestyle play a huge role in our health. As the founder of the Institute for Functional Medicine, Jeffry Bland MD writes in his excellent book The Disease Delusion:

“Genetic inheritance is not fate. Your lifetime health was not predetermined at your conception. On the contrary: you have the opportunity – and the power – to shape your own pattern of health and longevity.”

As one example, exercise and stress levels can affect how our bodies use nutrients. Some of us store fat more readily than others. Some of us have low penetrant genes that affect how we respond to exercise. It’s crucial to consider these environmental factors and lifestyle choices when interpreting nutrigenomics testing results.

The need for more research

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Despite the progress in nutrigenomics, there remains much to uncover. More research is needed to fully understand the complex relationship between genetics and nutrition, and to improve the accuracy and reach of nutrigenomics testing.

There are considerable challenges in nutrigenomics, including:

  • Lack of understanding of genetics by mainstream healthcare practitioners
  • Limited nutritional education in medical schools, on average just 11 hours per degree
  • Lack of insurance for nutrigenomics testing, so people are paying out of pocket for tests

These challenges pose obstacles to the progress and accessibility of nutrigenomics. However, this promising science shouldn’t just be within reach of the rich and well educated. Moves to include more foundational units on nutrition in medical schools, and the 2024 Netflix series You Are What You Eat: A Twin Experiment, are all helping to shape public opinion on the importance of food.


Nutrigenomics testing opens the door to a new era of personalized nutrition, allowing us to tailor our diets to our unique genetic makeup for optimal health. From understanding the science behind nutrigenomics to the types of tests available and their interpretation, we’ve explored how this field can transform our approach to health and wellness.

While the benefits of nutrigenomics are compelling, it’s important to acknowledge testing covers low penetrance genes that are influenced by environmental factors and lifestyle choices. Nevertheless, as we continue to unravel the complex relationship between our genes and nutrition, the potential to improve our health outcomes through personalized nutrition becomes increasingly apparent.

In conclusion, nutrigenomics offers a promising path towards achieving optimal health. As we continue to learn more about our genes and how they interact with the food we consume, we can look forward to a future where personalized nutrition is not just a concept, but a reality for everyone.

Frequently Asked Questions

What is nutrigenomics testing?

Nutrigenomics testing shows how our genetics and nutrition interact. It identifies genetic variations to determine individualized nutritional needs and potential health challenges related to diet and genes. This testing helps understand the relationship between genes and diet for personalized nutrition recommendations.

How much does the nutrigenomics test cost?

Nutrigenomics tests usually cost from $250 to up to $400, depending on the provider. This includes the cost of the collection kit, shipping, laboratory analysis and a personalized PDF report.

Is nutrigenomics legitimate?

Nutrigenomics is based on accurate science and can show your potential for certain health conditions, or how your body will respond to nutrients, but it’s important to remember that genetic predisposition doesn’t guarantee outcomes. While the research is promising, the large-scale use of nutrigenomics for personalized nutrition is still emerging and should be discussed with a doctor if you’re curious.

How does nutrigenomics contribute to optimizing diet?

Nutrigenomics testing helps identify genetic variations related to nutrient metabolism and gives personalized dietary recommendations to optimize nutrient absorption and use.