Cocoa craving may start in gut

washington -- If that craving for chocolate sometimes feels as if it is coming from deep in your gut, that’s because, maybe, it is.

A small study links the type of bacteria living in people’s digestive system to a desire for chocolate. Everyone has a vast community of microbes in their gut. But people who crave daily chocolate show signs of having different colonies of bacteria than people immune to chocolate’s allure.

That may be the case for other foods too. The theory could eventually lead to treating some types of obesity by changing the composition of the trillions of bacteria in the intestines and stomach, said Sunil Kochhar, co-author of the study in the Journal of Proteome Research.

Kochhar is in charge of metabolism research at the Nestle Research Center in Lausanne, Switzerland. The food conglomerate Nestle SA paid for the study, but it wasn’t part of an effort to convert a few to the dark side, or even milk side, of cocoa, Kochhar said.

In fact, the study was delayed because it took a year for researchers to find 11 men who don’t eat chocolate.

Kochhar compared the blood and urine of those 11 men to 11 others who ate chocolate daily. All were healthy -- not obese -- and were fed the same food for five days.

Researchers examined the byproducts of metabolism in the blood and urine and found a dozen significant differences between the two groups. For example, the amino acid glycine was higher in chocolate lovers, while taurine (an active ingredient in energy drinks) was higher in people who didn’t eat chocolate. Chocolate lovers also had lower levels of the bad cholesterol, LDL.

The levels of several substances that differed between the groups are linked to different types of bacteria, Kochhar said.

Still to be determined is if the bacteria cause the craving, or if early in life people’s diets change the bacteria, which then reinforces food choices.

How gut bacteria affect people is a hot field of scientific research.

Past studies have shown that intestinal bacteria change when people lose weight, said Dr. Samuel Klein, an obesity expert and professor of medicine at Washington University in St. Louis.

Since bacteria interact with what people eat, it’s logical to think there is a connection between microbes and desires for certain foods, said Klein, who wasn’t part of Kochhar’s study.

Kochhar’s research makes so much sense that people should have thought of it earlier, said J. Bruce German, professor of food chemistry at UC Davis. While five outside scientists thought the study was intriguing, Dr. Richard N. Bergman at the USC School of Medicine expressed concerns about the accuracy of the initial division between those who wanted chocolate or were indifferent to it.

What matters to Kochhar is where the research could lead.

Kochhar said the relationship between food, people and what grows in their gut is important: “If we understand the relationship, then we can find ways to nudge it in the right direction.�