A study from the Mayo Clinic supports a similar one in Israel, finding that each individual’s body reacts differently to similar foods.
If you and your partner or best friend eat the same foods but react differently, you might be able to blame differences in your gut microbiomes—the mix of bacteria in your digestive system—as well as your individual genes and physiologies.
The researchers’ goal for this study was to be able to predict individuals’ glycemic responses to foods. Analyzing the composition of gut microbiomes, which varies between people, and other factors is more accurate than predicting the reactions based on different foods.
Summary: Personalized diets based on one’s physical characteristics and gut biome may be the most effective way for people to manage their blood sugar, according to the findings of Assessment of a Personalized Approach to Predicting Postprandial Glycemic Responses to Food Among Individuals Without Diabetes.
The study: A growing body of evidence shows that individuals’ glycemic responses to the same foods differ greatly, depending on each person’s physiological and genetic characteristics, as well as the makeup of their gut microbiome. The microbiome might affect the body’s energy metabolism and its regulation of insulin.
Using a regression analysis that involves thousands of decision trees, researchers predicted participants’ post-meal glycemic responses to meals with a pool of 72 features:
The amount of carbohydrates, fat and protein in a meal; the number of calories and carbohydrates consumed at certain intervals before a meal.
The participants’ baseline blood-sugar levels.
The participants’ physical characteristics, physical activity, sleep quality and more.
Information from the continuous glucose monitors.
The levels of various bacteria in participants’ gut microbiomes, as determined from a stool sample.
The findings: The results showed “a wide variation in individual glycemic responses to the foods consumed,” the study reported. Each individuals’ results were consistent, but results between participants ranged from 6 milligrams of glucose per deciliter of blood to 94 mg/dL, with a mean of 30.7 mg/dL.
Study conclusions: The researchers’ model, based on each participant’s gut microbiome, correctly predicted the body’s blood-sugar response 62 percent of the time. When predictions about blood-sugar response are based on only carbohydrates, they are correct 40 percent of the time; when based on calories alone, the predictions are correct only 32 percent of the time.
This study confirmed the 2015 findings of an Israeli study, Personalized Nutrition by Prediction of Glycemic Responses that included 800 people.
Why the research is interesting: High glucose levels are related to diabetes, heart disease, obesity, vision loss and heart disease. The results of this study explains, in part, why some people are energized after they eat fruit but others suffer a blood sugar spike that causes them to feel tired later.