How Nutrigenomics Explores Links Between Nutrition And Genes

Forget a lot of what you think you know about nutrition, diet, and health. It could very well be wrong. As nutrigenomics makes scientific and technological strides forward, it brings into question a more subtle approach toward the issue of how what you eat leads to certain health issues. 

What were once secrets about how food affects the body are being revealed, as connections are being made between nutrients and your DNA. The potential is huge in that the fundamentals of nutrition, and how it impacts individuals could truly be discovered at a genetic level (via Proceedings of the Nutrition Society).

It was British physician, Sir Archibald Garrod, who in 1923 published studies making the link between diseases and genes (via DNA from the Beginning). In the 100 years since, scientific understanding about genetics has grown at an astounding rate. And while nutrigenomics hasn't provided the immediate solutions that perhaps was hoped for, it's fast becoming a huge scientific discovery. Nutrigenomics is growing, and the global market is expected to increase by more than $690 million between 2022 and 2026 (via Globe Newswire). 

As more sophisticated ways of seeking out genetic information and how it relates to nutrition are developed, the world of health and diet (as you know it) could be changed dramatically. Understanding your health in the future could come down to healthcare providers looking at your DNA, and what works for someone else nutritionally may not be right for you. 

Let's take a closer look at nutrition and genes and the complex nature of nutrigenomics. 

Understanding nutrigenomics

Nutrigenomics is essentially the science that links up the relationship between what you eat and your genes, and how this relates to your health. The idea is that nutrition feeds messages to your body, through genetic expression. And since there are differences between your genetics and somebody else's, these directions on metabolism and other processes vary. Nutrigenomics seeks to decipher these codes by understanding the relationship between nutrition, genetics, and disease. By focusing on this area, scientists are coming up with new research, tech, and techniques that could — in the future — build up a clearer picture of how genes relate to a multitude of issues such as obesity, type 2 diabetes, and heart disease (via Journal of Food Science and Technology)

If nutrition has an impact on how genes behave, and this impacts health, then genes can also have an impact on how the body deals with food in the first place. This relates to how you absorb nutrients and how they are used, as well as your body's metabolic rate. Therefore, nutrigenomics is really the study of not just how nutrition impacts genes, but also how genes have an impact on nutrition. 

Examples given by an article in News-Medical Life Sciences include a gene that corresponds to the activity of an enzyme that breaks down the sugar in milk. "Lactose intolerance is caused by the reduced function of a gene that codes for the enzyme lactase. This enzyme breaks down the disaccharide sugar lactose, present in milk and other dairy products." Those who have this condition are advised to avoid dairy products as a result. 

The science behind the nutrition and genetics link

There's no doubt that nutrigenomics is an emerging science — so while there are a lot of questions, the scientific answers are not fully ascertained. However, the United States is at the forefront of research in this area, as is the U.K., with scientific study relating to several different disciplines ranging from medicine to agriculture. In essence, this area looks at how nutrition affects the body on a molecular level. Therefore, the science involves looking at these relationships between food and genes, as well as nutrition and metabolism and protein levels. It's looking at the characteristics of genes, at how they behave and link up, and whether they're active or not active in terms of how they interact with nutrients (per National Center for Biotechnology Information).

Nutrigenomics looks at a great many variants, and how different interactions and resulting reactions work. As a science, it seeks to create a more complex understanding of how these variations operate at the same time, and what effect this has in relation to health problems. 

While links have been made, it's this complicated network of varied gene expressions, and genetic differences, that really makes this science so challenging. And even if more answers are found, the big question is whether personalizing nutrition in response to your genes will make as big a difference to health as to be of significance (via The Nutrition Society).

The history behind the science

Thousands of years ago, the gene that enables people to digest lactose was 'turned on' in some people in adulthood. In most people this was 'turned off' beyond infancy, but as people were consuming dairy in Europe, this changed. Obviously, if you're part of a society that drinks milk, for example, then having this gene expression is useful. It's only been in more recent times, however, that research has really taken off as scientists look for more gene interactions with food.

Of course, the study of nutrigenomics wouldn't be possible without great advances in genetic research. And this really took a giant leap forward since the early 2000s, with the Human Genome Project. This was a springboard for scientists to really look to the relationship between health, genes, and nutrition. (via Journal of Food Science and Technology). 

The Human Genome Project ran from 1990 until 2003, and created a sequence for the human genome. This meant that scientists and researchers had a "blueprint" and were able to understand how DNA was ordered, so they were able to break genetic code (per the National Human Genome Research Institute). This means that individual genes could be identified, which builds a better understanding of how different genes and gene mutations affects certain health issues (per Alcohol Health and Research World). 

Today, the Human Variome Project collects information on the connection between gene variation and health. 

Why nutrigenomics is important

There's a long way to go before nutrigenomics provides enough answers to really make a difference to individual lives. However, the reason this science is so important is that it's purpose is to support a healthier life. The whole point of it is to generate information about nutritional and genetic interactions for individuals. In the future, this could mean that you're able to tailor what you eat depending on your genetics. In turn, this could create a safety guard against certain health issues if you're able to change your nutritional intake to match your DNA. 

The right diet isn't the same for everyone, and having your genetic makeup at your fingertips could be the key to becoming (and staying) healthy. Of course, environment plays a factor, and how this and genetics interplay is crucial to better understanding (via MedCrave).

Working out your own personal story between nutrition and genetics extended to a societal level, feeds into issues around sustainability and diets of populations. Nutrigenomics could inform lifestyle choices so that health concerns are treated, as well as being prevented. Given the scale of the problem of preventable diseases that are directly related to what people eat, nutrigenomics could alleviate certain health stresses on a global level (per The Nutrition Society). 

In essence, the more that is understood about nutrition and genomes — as individual disciplines, and how they interact — the more easily people can take their own well-being into their own hands. 

Leading the way to more personalized nutrition

Better understanding of nutrigenomics means that gene variations that are expressed in a certain way as a result of nutrients you ingest can be identified. If you personally know this — about your own DNA, for example — then it really changes what you're going to eat. If you think about the diet industry, and how homogenous concepts are constantly pushed as the cure-all for weight-loss and other health benefits, then nutrigenomics threatens to turn that idea on its head. 

Of course, nutrition has an environmental impact on health. In fact, "Nutrition has the most important life-long environmental impact on human health" (via National Library of Medicine). Within this scope, nutrigenomics leads the way to more personalized nutrition and this in turn has wider implications.

Nutrigenomics identifies how cells are affected by nutrition, and how this branches out to impact health as a whole for an individual. What's nutritionally great for one person may result in a different gene expression in another. With this in mind, advice and support with regard to nutrition may be guided by these findings in the future; this guidance pertains to what specific nutrition an individual needs in order to inspire excellent health habits. In turn, this will impact the food industry, and while today certain foods are targeted at specific groups, the advancements in nutrigenomics could fine-tune what's offered to consumers. 

Different genes react differently to cholesterol

A Canadian paper from the University of Manitoba, published in Nutrition Reviews takes a look at the link between the food you eat and how the body metabolizes cholesterol. This is of real importance in terms of health, because of the connection between cholesterol and cardiovascular health. Advice to protect the heart (including diet guidance) is based on protecting against the presence of high cholesterol levels. And given that resulting heart disease is one of the leading causes of death — it's the main cause in the United States — understanding what affects the prevalence of coronary heart disease is vital to helping fix the problem (via the Centers for Disease Control and Prevention).

After reviewing the study of how genetics relates to cholesterol, it was suggested that different genes react differently to cholesterol. So, if a person has high cholesterol, for example, the dietary advice may have an impact in one person that's far greater than it is in another. This is what's clear: There are a number of genetic and nutritional interactions that relate to cholesterol, with many variants to explore the gene-diet relationship, notes Medical News Today

While more research is needed in this area, the more that is known about how genetics are impacted by nutrition, the more easily diet can be adapted to take this into consideration and tackle (in some way) not just cholesterol, but a disease that kills 17.9 million people globally every year (via World Health Organization). 

Nutrigenomics and obesity

Obesity in the United States is a big problem, affecting some 41.9% of adults, with a greater prevalence in non-Hispanic black adults in comparison to white adults. Costing the economy billions each year, the issue has worsened over the time. It's not just an issue of aesthetics either — being obese is connected with a whole raft of health problems, from type 2 diabetes to heart disease and stroke (via CDC). 

With low nutritional quality available for so many people — poverty being a big issue, as well as the prevalence of fast food — it's little surprise that obesity is becoming a symbol of the health of society in the U.S. and beyond. It's hardly a revelation that diet has an impact on obesity levels. However, genetics can lock or unlock the potential of diet (via CNN Health). 

For example, a variation of a certain gene was revealed by the Jean Mayer USDA Human Nutrition Research Center on Aging, to have a relationship with fat absorption, as reported by the U.S. Department of Agriculture. What does this mean? Some people can eat more saturated fat perhaps than those with this genetic variant who are more prone to putting on weight. This weight gain also has a knock-on effect on cardiovascular health, too. 

Food additives and packaging could impact genes

If you thought it was just nutrients in food impacting how your DNA works, then what about food additives and chemicals in packaging? Monica Dus, assistant professor at University of Michigan, told The Conversation that nutrients "trigger genetic switches that reside in the genome." She goes on to explain how additives may play a role in the "genetic instructions" that are created as a result of nutrition. If you think of information within a cell, then certain additives may interfere with that data, resulting in potential health issues. 

In the American Journal of Clinical Nutrition, an article looks at the impact of an abundance of folate and how this could be detrimental to health when combined with a lack of B12. Yet, folate is an additive that Dus points out is added to some breads and cereals. 

Dus also points out there are chemicals found in plastic packaging that's used for foods. What role does this play in changing genetic reactions? Could certain compounds be responsible for activating genetic switches or disabling them? And if so, what health issues does this cause? An example of this is BPA in plastics which has an impact on these genetic triggers in key developmental areas, and the fear is that this is physically harmful (via International Journal of Molecular Science). 

Writing for The Conversation, Dus explains that BPA "turns on genetic dials in mammals that are critical to development, growth and fertility. For example, some researchers suspect that, in both humans and animal models, BPA influences the age of sexual differentiation and decreases fertility by making genetic switches more likely to turn on."

These are all questions for nutrigenomics, and demonstrate how this subject isn't just about what you eat, but touches on how genetics are impacted by the environment, food production, and even laws.

Genetic testing could affect what you eat

There's an old adage that the right diet is about listening to what your body needs. However, the story your body is telling is one where the real plot is not about likes and dislikes, but actually about how your genetics manipulating your preferences and reactions to foods. In order to tap into this genetic narration so you can make an informed choice about your dietary needs, you need to know what your DNA is saying. The Cleveland Clinic notes that such knowledge isn't about giving in to what might be genetic weaknesses, but feeling empowered to take control of what your body needs. 

Testing of genomes — with the help of a dietician — can change what you eat by alerting you to a propensity to be affected by food in a certain way. You don't need to be a scientist to know that certain people have a sweet tooth more than others, while some are really impacted by caffeine, and that there seem to be differences in how people react to carbs. If nutrigenomics ideas are to be followed, then the only way to unlock individual genetic quirks is to test them.

Testing genetics so that you can adopt a DNA diet may be able to be combined with other data to pinpoint a better nutritional direction — it may be a good motivator in improving diet and lifestyle changes (via BBC Food).

The connection between appetite and genes

There are some people (and even cultures) who eat small meals often. You might suddenly feel satiated while you're eating, but others aren't full until they've eaten too much. Nutrigenomics may look at how macronutrients and micronutrients play a role in how gene variations express themselves, and how they can compromise health. However, there's also evidence that your genetics are also involved with your appetite, too. So the link extends beyond what you eat to how much you want to eat (via Labroots).

A gene has been pinpointed that activates once you've eaten enough food. However, a U.K. study from Cambridge Biomedical Research Centre, published in 2020, related that 300 mutations of the gene had been discovered. Looking at the DNA of half a million adults aged 40 and over, and younger than 70, it was shown that the gene doesn't always do what it's supposed to (via The New York Times).

On top of this, one variant actually led to a smaller appetite giving them a less likely chance of being obese and suffering from the myriad health problems associated with excess weight. It could be (in the future) that weight control measures concerned with appetite may be more focused on what to do with this genetic information rather than other factors. Medications may reach out to specifically combat the effects of genetic differences, while more research is needed.

Genetics influence food preferences

Have you ever considered that you're genetically programmed to love or hate certain foods? If genetics can influence (and be influenced) in terms of how they act regarding nutrition — and appetite can be determined by your DNA — then why not the foods that you want to eat too? It's not by chance that so many people find truffles irresistible, while many people don't get the whole truffle craze. This has to do with genetics. It's also the case with cilantro, which is another love-it-or-hate-it food. Apparently, it's a genetic mutation that makes cilantro taste like soap to 14% of people (via Detroit Free Press).

While genetics do play a role in what foods you like, they're not the only factor, and this is why developing your palate by trying different foods can be interesting. You're not at the mercy of your DNA preferences, except perhaps when it comes to truffles and cilantro. Other influential factors include age, with your tastes (and taste buds) changing over time, while hormones can also have an effect. 

Meanwhile, trying different foods means that you may get used to the taste, and so, broadening your culinary horizons is worthwhile. If you've not enjoyed a certain dish in the past — maybe because it wasn't cooked well — then you may want to try an improved version to see if you definitely have an aversion. 

Issues on accessing tests and advice

As research progresses in the field of nutrigenomics — extending into so many areas — it also brings up issues that relate to ethics, legalities, and social affairs. These involve testing, as well as access to testing, along with data and any subsequent advice. For example, questions about how to monitor and create the right checks and balances regarding over-the-counter nutrigenomic tests arise. So too, do legal concerns about what the claims that are made by companies providing testing (and also those involved in supplement markets) and what the results mean (via Science Direct). 

However, while restraint in the private sector may be sought, the public healthcare sector is far from geared up with knowledge about nutrigenomics. That means that patients are not being offered opportunities to explore their own health issues through this prism. Physicians don't generally have the tools — and while this is the case, it's also less likely to hold back those healthcare businesses that are jumping fully into the gene-nutrition arena. As the genetic factors relating to nutrition become clearer, the public's quest for testing and advice is bound to grow exponentially. 

And if healthcare professionals are not offering this more personalized nutritional plan, then people are going to want to seek this information elsewhere. It'll be interesting to see how access plays out, and whether it's mainly nutritionists who are clued-up on the gene-nutrition link, or whether general physicians will be able to offer support in this area as well. 

Impact on the food industry

Anything that changes the way individuals and medical professionals view nutrition is undoubtedly going to be reflected in other areas. And an obvious one, no doubt, is the food industry. Whatever the real difference gene variations make in terms of health, the reality is this: The more that's discovered, the more reactions are going to be experienced in different ways, and on different levels. 

It's already the case that foods are sold that are enriched in some way, or it's highlighted how they're rich in certain nutrients. At the same time, foods for specific diets, such as keto, to treat certain ailments are also available. As nutrigenomics advances, nutrition plans can be created for certain genetic groups (via Indian Journal of Horticulture). 

There have long been diets and food products targeted at specific health conditions — keto is aimed at lowering blood sugar levels and tackling type 2 diabetes, for example (per Healthline). This is whereby a variant of one gene has led to a disorder of some kind and there's a direct connection. However, nutrigenomics is more expansive, and more complex perhaps, as it may be that a number of genetic variations impact a number of different responses to nutrition. It's when these multiple changes are combined that they create an outcome. 

The result is food that's created to deal with these differences. A University of Auckland study, highlighted in a Healthy Food Guide article, focuses on a gene-diet factor in why Crohn's disease is higher in New Zealand, and one area in particular. The guide explains, "The research team is studying the link between foods eaten by people with Crohn's disease and different variations of the disease-related genes. Information about lifestyle and symptoms are also collected to learn more about the disease and potentially to allow tailoring of foods to genetic type."

The future of nutrigenomics

Nutrigenomics applies genetic sequencing. Now that DNA has been unlocked, nutrigenomics is a way of following those biomarkers in more detail and seeing where they lead as a result of how nutrients affect genetic behavior. The hope is that this will pave the way for more personalized nutritional advice, and the know-how on preventing certain diseases where there's a predisposition lurking in the DNA. So far, the full story of diet and disease isn't known, and nutrigenomics could fill in those missing gaps. 

Ahmed El-Sohemy, expert in nutrigenomics at the University of Toronto, explains in Today's Dietitian, "I've moved to using nutrigenomics as the umbrella term to cover gene-diet interactions." However, while the world catches up, Stanford University professor Christopher Gardner points out that regardless of the difference individual nutrigenomic factors make, the fact remains that general diet advice about not eating excessive amounts of sugar, for example, still stands. 

As more is known about nutrigenomics, the more easily businesses can offer targeted solutions. Technological advances may mean that nutrition becomes more personally managed, too, such as through apps. Meanwhile, it's also noted by Dr. El-Sohemy that there may be more people who have different genetic responses to nutrition than is expected (via BioMed Central). 

Wearable medical devices, for example, may monitor the food you eat, and the effect it has. It could be that what you eat is also digested by analytical processes (embedded within these wearable units) that provide immediate feedback concerning health and nutritional needs.