Dr. Eran Elinav is a professor at the Department of Immunology, Weizmann Institute of Science, and since 2019, the director of the cancer-microbiome division, at the Deutsches Krebsforschungszentrum (DKFZ), Heidelberg, Germany. Dr. Elinav is also a co-author, together with Prof. Eran Segal, of the book, The Personalized Diet, summarizing some of their research on personalized nutrition.
What is the role of our microbiome in our personalized diet?
Dr. Elinav: Being a microbiome lab, the microbiome was an integral part of the person-specific data that we collected, but at the time, we didn't know if it was important or not. But following the completion of the project, we were able to revisit each person's algorithm after it was formed without asking us to check what features from a given person were more or less important for the generation of this prediction. We were very much surprised to find that a large chunk of the features that the artificial intelligence system chose to use relates to the gut microbiome. In other words, the gut microbiome seems to be one, not the only but one of the central person-specific signatures that contributes to the ability to predict a person's response to different foods.
There are some books also talking about calling our microbiome our second brain. Is there an ideal microbiome or is there a way to bring our existing microbiome into an ideal state?
Dr. Elinav: Because the microbiome field is very young, we're only just about a decade or half old, so it's still in its infancy, many features of the microbiome are still very much not understood. At the beginning of the microbiome field, we were all following a romantic notion that we will find the healthy or the ideal human microbiome. But with growing knowledge and maturity, we realized that probably there is no one good or ideal microbiome. And if we sequence people deeply enough, we find that different people have unique signatures of microbiomes compared to one another. What we are slowly starting to understand is that rather than looking at the different bacteria that comprise a given microbiome, it is more important to look at the functions that these communities of microbes bring to the human body. And when we look at functions, rather than at the names of the bacteria, we find more similarities between healthy microbiome to different people or disease-associated microbiomes to people that are prone to develop a disease.
Could you tell us where is the best place to start with a personalized diet and to find the right food for us to create an individual lifestyle plan and diet to increase vitality, prevent disease and increase our healthy longevity?
Dr. Elinav: We’d rather be careful, although our studies have now been followed by several notable groups from other countries. They have reproduced our findings mainly relate to the control of blood sugar levels. This is very important and has very great implications on health because maintaining healthy and lowering your blood sugar levels is important not only for the prevention or treatment of diabetes, but also is associated with obesity, fatty liver and heart disease. However, we do not mean to over interpret our findings to provide any evidence at the moment that this diet is good for other diseases such as cancer. All of these other dietary health connections need to be studied before we come to any conclusions.
We were very much surprised to find that a large chunk of the features that the artificial intelligence system chose to use relates to the gut microbiome.
Dr. Elinav: In implementing the personalized dietary approach, to try to lower or normalize blood sugar level, one can do this in several different manners. In the book, we provide all the different levels that one can implement, to use this knowledge for the benefit of their health. The simplest way is to just buy a glucose measurement kit from a pharmacy and measure your individualized response to given foods that are of interest. We discovered that people usually consume 50 or 60 different food ingredients in regular life. So you can choose your favorite foods and just eat them. We provide the exact details in the book and measure your blood sugar levels after you ate a given food or food combination that is something you usually eat. And do this repeatedly. Then you can know what your personalized response is and can mix and match, change the combinations of foods if the spikes are too high, and reach more optimized food combinations that will bring your blood sugar levels down. If you're interested in doing this in a much more sophisticated way, you can connect with the spin-off company DayTwo by logging into daytwo.com on the internet. They would generate using stool samples and a clinical questionnaire, a much more elaborate machine learning algorithm that uniquely fits you. With this algorithm, you will be given recommendations for any given food. Even foods you've never tasted and food combinations that you can choose to give you a more diverse solution to your dietary personalization. It is a kind of do-it-yourself home-based system which is very cheap, very accessible, and limited because you have to choose only the foods that you would know about or choose the more comprehensive commercial solution that will give you broader data.
Does this data provided by DayTwo tell us about the food that is good for us as well as the food that we should avoid?
Dr. Elinav: Exactly, and with the maturation of the project, they've done tens of thousands of people and learned that there is no one food that is usually bad for us, it could be a food that is bad for us in a given combination. But then you change some of the combinations in a given meal and the food that was bad for us in one combination becomes better for us in another combination. So the big advantage of this system is that it usually doesn't lead to complete avoidance of a food that you like but provides you with the right combinations that together would improve your sugar control, but would still enable you to consume in moderation. It is important to state that even with this system, it doesn't mean that if for example, ice cream is good for you, we do not recommend that you eat five kilos a day because the calories still matter. You still need to comply with a caloric overview of your diet. But within that caloric content, you can mix and match your foods better to maintain a better sugar control.
This is very good news, especially about the ice cream. So where do you see the future of personalized medicine and nutrition?
Dr. Elinav: I think that personalized medicine or precision medicine is taking off in many different fields. For example, the leading field is cancer. Today, we are able to tailor different treatments against different cancers to the individual and to greatly increase our chances of succeeding. Precision medicine is going to expand into further medical fields. I think personalized nutrition in the future will be integrated into medicine as another important tool that would enable us to optimize the treatment of different diseases. Now we are doing this for sugar control because it's easy, important and this is the data we have. But I don't see any reason why future studies will not be able to explore the rules of personalized nutrition as impacting other body processes in health and disease. And when we do and understand better, we would be able to integrate personalized nutrition into this precision medicine scheme in providing more holistic solutions for different disease conditions by using science and data coming from the individual in order to optimize treatment.
To contine this article please look forward to The future of nutrition - part 1