The bread battle is a key feature of any self-respecting diet. To eat or not to eat bread? And if so, which color?
How big a difference is there really between eating white bread and eating whole-wheat bread?
Scientists in Professor Eran Segal’s laboratory at the Weizmann Institute tested multiple blood markers of ten people who ate white bread for one week and sourdough whole-wheat bread the next week, matching both breads on carbohydrate content. Another ten people followed the same regimen, but in the reverse order.
Surprisingly, although one week of bread consumption affected blood test results, no differences were found between the two types of bread.
One of the effects of bread – or any food – on our body is reflected in the glucose levels in our blood. The scientists found significant disparities among different people in their blood glucose response to bread. In other words, each person had a different glucose response to each type of bread. This personalized effect of bread could perhaps extend to other physiological processes
The researchers also measured levels of microbes – intestinal bacteria that live inside all of us. The researchers found that the composition of microbes was unique to each person throughout the experiment, and this makeup of microbes predicted the blood glucose response better than the type of bread.
This means that general dietary recommendations are not enough; the best menu for each of us is also determined by our individual characteristics.
The scientists found that such a short-term nutritional change does not have a major effect on the population of gut bacteria. If intestinal bacteria do not change the moment we change our diet, this enables us to use their composition to personalize our diet.
But what if future research discovers how to change the makeup of our microbiome? Could we then program it to let us eat chocolate without gaining an ounce?