Have you ever wondered why a particular diet may work well for some, while others struggle to get results following the same way of eating? Gone are the days of a one-size-fits-all approach to nutrition. Enter DNA-based nutrition, also known as nutrigenetics or nutrigenomics.
Variations in our genetic makeup not only determine the colour of our hair and eyes, but it’s now recognised that the unique differences in our genes can also impact how effectively our bodies break down and metabolise the food we consume, which can directly affect our health. Whilst 99% of our genetic makeup is identical, there’s around 10 million genetic variations among individuals and therefore across the population, we will have varying nutritional requirements and different responses to certain foods and nutrients. Therefore, a more personalised approach to nutrition is now considered to be the best course of action.
What does nutrigenomics tell us?
The link between genetics and nutrition is an ever-growing area of study to understand how our genetic makeup can impact individual nutritional requirements and how certain nutritional factors may protect DNA from damage. DNA (short for deoxyribonucleic acid) is the molecule that contains the genetic code of humans (and all living organisms). Genetic variations can cause a different response to certain components in food such as the gluten in bread and pasta, or the caffeine in tea and coffee, along with proteins, carbohydrates, fats, vitamins, and minerals present in many foods. This explains why some people are intolerant to certain types of foods, whilst others experience no discomfort or issues consuming the same food.
Our genetic makeup is fundamental to our health and one gene in particular that’s becoming better understood is the FUT2 gene. The FUT2 enables us to produce an enzyme called α1,2-fucosyltransferase (or 2-FL). This enzyme is used to produce glycans found in the mucus of the intestine and in saliva, which are part of the body’s natural defence system. Around 20% of the population have an altered FUT2 gene, which means that they are unable to produce this enzyme. These individuals are referred to as FUT2 non-secretors, whereas those who can produce the enzyme are known as FUT2 secretors.
The inability to produce the 2-FL enzyme has been shown to have some consequences to health as this enzyme is a key nutrient for many beneficial bacteria (namely bifidobacteria) in the gut. Therefore, a lack of this enzyme will usually result in significantly lower levels of beneficial bacteria, which can result in a weaker intestinal barrier and an unbalanced immune system. In addition, FUT2 non-secretors have an increased risk of celiac disease, IBS and type 1 diabetes.
A lack of beneficial bacteria in the gut, known as an unbalanced microbiome, has also been shown to produce less essential amino acids and vitamins such as tryptophan and tyrosine which are essential for a healthy nervous system. However, our diets have a direct impact on our gut microbiome and eating a balanced, varied diet has been shown to support a more resilient and healthier gut microbiome. Eating foods high in fibre (e.g., wholegrains, legumes, vegetables, and fruit) and probiotic fermented/pickled foods (e.g., yogurt, kimchi, kefir, sauerkraut, miso and kombucha) will help improve gut microbiome, along with many other powerful benefits a healthy gut provides for both physical and mental health.
Consequently, understanding your unique genetic profile and its implications for your body’s response to the foods you consume can be an incredibly helpful tool as this enables you to make informed dietary choices to best suit your specific nutritional needs. However, DNA is not diagnostic and only one aspect of a more complex picture. Lifestyle and environmental factors play a hugely significant role in our overall health and should be treated as a priority. Protecting our DNA starts with what we put on our plate.
Personalised nutrition is becoming more widely recognised and is predicted to have a strong future in health management and disease prevention. Further down the line nutrigenomics may even be utilised as a method of enhancing athletic performance. Understanding how our specific genes respond to different dietary components allows us to utilise nutrition to its fullest potential to improve, manage and even prevent various health issues. Genetic testing also enables us to reduce or manage our intake of certain food groups or substances such as caffeine or alcohol which we may unknowingly be sensitive or intolerant to. By tailoring our nutritional requirements to complement our genetic makeup, we can maximise the benefits that nutrition can have on our health and wellbeing. Our genetic information remains the same throughout our lifetime so you can carry the knowledge you gain about your unique genetic makeup with you throughout your life to support your health and longevity.
About the author
Stephanie Yates is a nutrition coach and writer with a BSc in Food and Nutrition. She utilises her knowledge and passion for nutrition and fitness to deliver evidence-based, informative articles and guidance, helping others meet their fitness and health goals to feel their best – inside and out. You can find her on Instagram @electricmango__ for more fitness and nutrition tips.
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