Bluetree clinic nutritionist Charlotte Turner talks about
Imagine you are in a department store, selecting the perfect foundation for your skin type or in a clothes store selecting a shirt. In both of these scenarios you would be offered personalised choices. Be it what foundation is applicable for your skin tone (lightweight or medium coverage) or what shirt suits your body shape (slim or regular fit ) this same choice is very much limited when it comes to the diets and foods we consume.
There is no agreed definition of personalised nutrition, but personalised nutrition in a nutshell simply means tailoring nutrition recommendations to the individual based on their own individual characteristics. In today’s world all the nutritional information printed and provided to us on the side of food or vitamin products is generic to the general population. The maximum amount of personalisation we tend to receive is based on our gender and stage of our life i.e child, teenager or adult.
This personalisation problem is compounded by the fact that historically the guidelines provided had to be unambiguous and clear so all of us could understand. For example, why do we all take the same vitamins and follow the 2000 kcal requirements stated on the packaging? These dietary reference values (RNIs) are set through epidemiological analysis of population. This means that the recommendations would safely over achieve the needs of 97% of the population which ensures we all meet most vitamins and minerals. The error of this broad guideline however is that some of us would be over consuming are daily calorie intake.
In the personalised genetic space, there is a growing body of scientific research which shows that vitamins can be tailored based on the lifestyle of the person, their dietary habits and their generic make-up. For example, take an example gene in the body, the MTHFR gene. This genes role is to convert folic acid into its preferred form methyl-folate through the action of a specific enzyme. Approx 30% of the population hold different genetic variants (also known as SNPs) of this MTHFR gene meaning that they may find it hard to convert certain nutrients into the best form their body needs. This then means these individuals require more folate (i.e. They should consume more dark leafy vegetables) in their diet to compensate for this inefficient enzyme. The risks of lower folate intake have been associated with increases in homocysteine a precursor to heart disease risk amongst other risk factors.
Personalised genetic testing in this example could help individuals to make dietary changes, which in turn reduces their predisposition to certain health risks . The focus here however will be on the individual to choose to make those dietary changes.
Companies are now allowing individuals to gain a better understanding of their nutrition needs through the rise of DNA testing. This trend is leading individuals to appreciate that one size doesn’t fit all, allowing them to optimise their diet accordingly. In the past, cost was a barrier to obtaining their DNA profile, however this cost has rapidly reduced allowing the potential for mass market or even state funded DNA profiling to provide more of a personalised solution.
So if the price of DNA profiling is going down we are going to get to a point where more and more people look at understanding their DNA, we will need to uncover whether personalised nutrition can work in reality. This starts with the science behind how food companies determine our nutritional needs.
Personalised nutrition is starting to utilise this approach in two very clever and exciting ways;
- The first is to assess your unique requirements using advanced algorithmic questionnaires that take into account a multitude of your personal characteristics such as age, gender, daily habits, your sleep, stage of life, what you eat and any health issues you experience. Using this data your requirements are then tailored to your needs based on your current life stage (pregnancy, increased fitness training or retirement)
- The second and perhaps the most clever is the rise of nutrigenetics.0.1% of our genes vary which is why we are all unique not just in terms of eye or hair colour but also what aspects of diet and exercise affect our health and fitness potential. These new DNA tests take a saliva swab and test for the most common and more importantly the most researched diet and nutrition genes and what that means for the individual.
These genetic tests then can advise certain recommendations for your daily nutrient intake based on whether you need higher sources of certain nutrients or whether you are more sensitive to caffeine and alcohol for example. A word of caution though is that these genes highlight a predisposition to your dietary preferences but health and lifestyle changes should be holistic that take into consideration your lifestyle and environment and not just genetics.
In one sense this personalised nutrition trend is exciting as it give us the ability to learn more about are bodies and our unique make up. However, it still remains to be seen that once we know that we hold certain genetic variants this would actually motivate us to change our dietary habits. Lastly, even in the far future when we all hold our unique nutrition profile, wouldn’t we still need generic nutrient intake guidelines on the back of the food packets to ensure from a public health perspective we meet our needs? How many of us would ever follow personalised recommendations down to a tee?