Some people indulge in all their favorite food but still do not gain weight, while others follow various types of diet to shed the extra kilos, despite which they fail to lose weight. For the first time, a study conducted in Israel has shed light on the reason behind it. The revolutionary study was carried out by a team at the Weizmann Institute of Science in Rehovot and led by Professor Eran Segal and Dr Eran Elinav.
Dr Saleyha Ahsan traveled to Israel to take part in the study as part of Trust Me, I'm a Doctor. The researchers monitored 1,000 people to study how their bodies react to food. Foods can make some individuals put on weight and have no effect on others. Every person reacts differently to different foods. The blood sugar level rises after each meal. Theoretically, it is suggested that some foods, for example, white bread, causes a sudden rise in the blood sugar level. The constant rise in blood sugar level can result in type 2 diabetes, obesity and increases the risk for other diseases. It is also thought that other foods, for example, whole grain rice does not drastically increase the blood sugar level. Therefore, foods have been classified as 'high GI' (glycemic index) food and 'low GI' foods, based on the rise in blood sugar levels.
‘Gut microbes might be the key to why the blood sugar level rises with different foods and vary with different individuals.’
AdvertisementGut Microflora is the Key
Based on the data collected from monitoring 1,000 participants, the researchers were able to make firm links between a person's individual response to food, and to their gut bacteria. The researchers have developed a computer algorithm that uses an individual's gut microflora to predict how their blood sugar levels may react to a whole range of foods. A study was carried out to test the accuracy of the algorithm, and it indeed appeared to predict the good and bad foods for individuals based on their gut microflora. This shows the vital role of gut microflora in regulating an individual's response to food and overall health.
The researchers carried out a small study using an algorithm and provided the list of good and bad diet for 25 people. The researchers took stool samples of the participants to discover the composition of the gut microbes. Every individual carries thousands of different bacteria, fungi, and viruses in their gut. These microbes help break down the food and also produce an enormous range of compounds that the body absorbs and that can have an influence on the immune system, metabolism, and neurotransmitters.
The study participants were given only the food 'good' for them for a week and 'bad' for another. The participants were unaware of the good and bad foods. Over the week, the researchers observed changes in blood sugar levels as predicted and also changes in the gut microflora of the participants. The changes observed during the week of 'good' food appeared to be beneficial. The results of the study suggest that personalizing diets based on an individuals response to food can benefit overall health.
The foods that were found to be good for Dr Saleyha's (who participated in the study) blood sugar levels included avocado, croissant, yogurt, granola, banana, walnuts, omelet, chocolate, ice cream and cola. The foods that were found to be bad for Dr Saleyha's blood sugar levels included, grapes, cereal with milk, pizza, pasta, tomato soup, chicken sandwich (on wholemeal bread), orange juice and sushi. In a short and uncontrolled trial, the gut microflora changed for the participants, who were given only the foods identified as good and avoiding the bad for two weeks.
In future, the researchers Dr Segal and Elinav hope to be able to make the results of their work available to everyone, worldwide. They hope to provide a list of foods that are predicted as good and bad for an individual to help maintain stable and healthy blood sugar levels. The research team also plans to study the long-term effects of diet on gut microflora.