Know anyone who has made a complete commitment to a weight loss diet and not seen any results? Recent research suggests that generic diets that work for some may not work for everyone based on differences in individuals’ genetics and medical histories. In lieu of generic diets, some researchers propose a more personalized approach to nutrition, one that takes into account individuals’ unique characteristics to guide diet choices.
The medical community agrees that diets generally do not result in long-term decreases in weight, but do diets often fail because individuals lose motivation and return to unhealthy eating practices or because of underlying genetic predispositions that some individuals possess? Israeli researchers sought to determine just that by measuring levels of glucose, a sugar found in our bloodstreams, in 800 adults for one week after they ate certain foods. The level of glucose in our blood serves as a crucial signal that our bodies use to decide whether we should store or release energy. Blood glucose levels rise when we consume food, and as a result, our bodies release insulin, a hormone that signals the body to store glucose as fat and muscle. In contrast, when blood glucose levels fall, the hormone glucagon is released, which causes our bodies to burn fat and muscle to provide us with energy. The Israeli nutritionists concluded from their study that blood glucose levels cannot be predicted merely though what foods an individual consumed. Instead, many personal characteristics such as our weight, the types of gut bacteria we possess, and our levels of blood glucose early in the morning had important impacts on the way our bodies process food.
In light of these discoveries, what can we do to improve weight loss diets and our health? It is clear that more research must be conducted to evaluate the long-term effects of dietary restrictions on blood glucose levels since the Israeli study only monitored volunteers’ blood glucose responses to certain foods over the course of one week. However, based 0n currently available evidence concerning personalized diets, some researchers advocate the development of personal nutrition apps that can recommend specific foods to eat based on inputted characteristics. By specifically tailoring nutritional guidance, these diet apps strive to improve the likelihood that individuals will lose weight from dieting. Gathering personal health data necessary for these apps may prove difficult. Widescale monitoring of individuals’ microbiota, a community of bacteria whose constituents are constantly changing, is currently infeasible and more work is needed to develop easy-to-use microbiome diagnostic tests. Moreover, individuals may not be willing to pay for glucose testing supplies and undergo the discomfort necessary to monitor their morning blood glucose levels. As the field of personalized nutrition matures, it is clear that scientists will need to account for the ease by which consumers can acquire health data in addition to potential efficacy that such data will have on dietary habits.
Acknowledgments: Many thanks to Adam Brown, a graduate student in the Department of Biomedical Informatics at Harvard Medical School.
Managing Correspondent: Edward Harvey
Original article: Personalized Nutrition by Prediction of Glycemic Responses – Cell
Media coverage: Could Your Healthy Diet Make Me Fat – NY Times