Until recently, the study of nutrition and genetics were separate areas but now scientists investigate the interaction between our genes and nutrition. This new area of study, known as Nutrigenomics, or in a more consumer friendly term “Individualised Nutrition”, is already providing promising information that could help us tailor dietary advice more effectively to prevent disease and promote health. In this week’s article discover the science of Nutrigenomics and how it could radically change the way in which we understand nutrition.
What is Nutrigenomics?
So, what do scientists hope to achieve? It is a very complicated process but in simple words, scientists take the individual’s DNA profile, which is their genetic signature, to the diet clinic and provide a pin-prick of blood. The blood sample is then analysed and compared to the DNA. The result is a dietary prescription tailored to the individual’s specific genetic needs and perfectly balancing their macro- and micro-nutrient needs. Each individual will be asked to follow a very specific diet plan tailored to their needs and goals. At the moment this is a fantastic scenario, but it is one that scientists are already predicting could become technically possible in the near future.
But this is not a simple task. If we use heart disease for example, there is not just one gene responsible for running the cardiovascular system; at least 20,000 genes are involved. In addition, there are numerous ethical issues associated with Nutrigenomics and therefore this subject has started a debate among scientists.
What are the potential benefits of Nutrigenomics?
• Individual diets
According to public health policy there is a set of dietary guidelines for all of the population. However, there are many examples of how individuals respond differently to diet. For example, vitamin and mineral needs vary between individuals and by age, condition, health, gender etc. For example, sodium increases blood pressure in some people but not others and the ability of dietary fibre to reduce cholesterol is also subject to genetics.
By using Nutrigenomics it will soon be possible to use genetic testing to screen for the risk of various diseases and to determine an individual’s ideal health promoting diet. It will become commonplace for health care professionals to deliver tailor-made drug advice based on an individual’s genetic information. Moreover, it will be possible for nutritionists to deliver more precise dietary advice.
• More nutritious foods
Ever wondered why some become overweight, some develop heart disease and some develop allergies while others do not even when they are eating the same diets. Research into the functions of genes will help to identify just how diet affects gene and protein functions and why individuals show a different response to nutrients and diets. Therefore, this knowledge can help in the development of even more nutritious foods. Specific foods with beneficial properties (functional foods) could then be developed to help optimise the health of each individual according to their genes. This may seem far in the future, but truth is we already eat foods according to our genetic differences. For example, women need to eat foods with more iron than men do. In addition, knowing how individuals develop allergies would lead to foods not simply to avoid allergens but foods that prevent people from even developing allergies in the first place.
One of the most intriguing areas of research that will eventually help everyone, is understanding the processes of ageing and diseases of the elderly. Scientists have found that about half of the diseases that come with ageing have a genetic component. Substances in foods can influence some of these functions so the possibility to delay ageing may not be science fiction in the future!
• Improvements in food processing
Another potential use of research into the functions of genes is to improve food processing of the raw materials of foods. Benefits would include optimal levels of various nutrients, easier and more economical processing, and of course safer or even more nutritious products. As a simple example, potatoes with higher levels of starch could be developed that when processed into potato chips or french-fries, would absorb less fat offering the choice of a low fat potato chip. Fruits and vegetables that have delayed ripening properties could be grown so that they can be transported more easily with less damage and arrive in stores fresher and tastier.
• Improvements in diagnosing disease
It has been known for centuries that many diseases have a genetic component. Scientists have already identified more than hundred genes linked to diseases such as breast cancer, muscle disease, deafness and blindness.
Information from the human genome is making it possible to identify the exact gene that influences a person’s susceptibility to the diet related diseases. These techniques can also be used to screen large numbers of people for the presence of such genes. Once high-risk individuals are identified, measures can be taken to help prevent the disease or detect it early when treatment methods are most effective. In the case of dietary-related conditions, these interventions will involve dietary changes often including functional foods.
No doubt that Nutrigenomics is a huge challenge for the future. However, the importance and complexity of the interaction between food, genes and health may be the key to understand metabolic problems such as obesity and diabetes and to identify of new more effective treatments. As it becomes possible to assess an individual’s genetic susceptibility to disease, it will become possible to create special foods and medical treatments uniquely tailored to help manage that susceptibility. There many ethical and human rights challenges associated with such practises. As with any new technology, people must be educated and open minded in order to make informed choices.
By Kleio Bathrellou