Why nutrition is personal?
Nutrition is personal because each of us eat the way it pleases; but also we have our own unique nutritional needs. These are not only determined by age, gender and physical activity but physiology, psychology and medical conditions. The age, gender and physical activity give general guidance for these categories. For example, the nutritional requirements of a teenager are different from a senior person. However even within the same age category and gender, there will be variations because each one of us has a different physiology that dictate our reaction to foods, how we process them and what is absorbed into our blood stream.
But what does reacting differently to foods mean? Most of us are familiar with allergy or intolerance reactions to some foods where some people may eat a certain food and feel perfectly fine, whereas in others it could trigger a severe reaction. Furthermore, in the metabolism level we react differently to the same food/ meal; this was highlighted by a study tracking the blood sugar levels of hundreds of people over a week suggesting that even if we all ate the same meal, how it’s metabolised would differ from one person to another (Zeevi et al, 2015). Even identical twins who share the same genes end up having different reactions to foods. One of the reasons is that only 30% of their microbiome is similar. The microbiome is made up of the different bacteria, viruses and other microscopic organisms that live in our gut. You can think of the microbiome as this huge jungle full of many plant varieties. In fact there are so many different organisms in our microbiome that studies have mapped 3.3 million kinds of genetic material found in poo. Our microbiome is unique to each of us like our finger prints.
A long time ago we thought these creatures living in our gut were just there to protect us from disease. But in the last decade researchers have found out so much more about this incredible ecosystem (though a lot more to be discovered). The microbiome can in fact determine our weight, contribute to metabolic functions, protect us against pathogens and educate the immune system (B. Shreiner, 2015). The microbiome synthesises vitamins and key metabolite that play a major role in our brain and heart health amongst other organs. For these reasons, it’s very important to care for and nourish our microbiome particularly when suffering from an auto immune disease, as it affects directly and indirectly most of our physiologic functions.
Therefore, our nutrition is personal because we each have a unique microbiome that makes us react and metabolise food in different ways.
Although there are a set of nutritional requirements for each known nutrient, there would be for example a person who might need more or less or none of a nutrient because of a medical condition or simply the way their body is absorbing/ losing it. People who suffer from coeliac disease should not gluten in their diet because it damages the gut lining, so this is personal to them.
Because our nutrition is personal, this makes our health and wellbeing a very personal story to each of us. This is why it is a good idea to pay attention to what affect different foods have on you and what your body is trying to tell you. My wise mum used to say you are your own doctor. Nevertheless, when we feel something is not quite right, we should seek professional advice not just merely looking for information on the internet because the advice you need is very much personal!
Andrew B. Shreiner,1 John Y. Kao,1 and Vincent B. Young. The gut microbiome in health and in disease. Accessed onDavid Zeevi, Tal Korem, Niv Zmora, David Israeli, Daphna Rothschild, Adina Weinberger, Orly Ben-Yacov, Dar Lador, Tali Avnit-Sagi, Maya Lotan-Pompan, Jotham Suez, Jemal Ali Mahdi, Elad Matot, Gal Malka, Noa Kosower, Michal Rein, Gili Zilberman-Schapira, Lenka Dohnalová, Meirav Pevsner-Fischer, Rony Bikovsky, Zamir Halpern, Eran Elinav, Eran Segal. Personalized Nutrition by Prediction of Glycemic Responses. Cell, 2015; 163 (5): 1079 DOI: 10.1016/j.cell.2015.11.001