Are You Sure Your Whole Wheat Bread Is Better For You?

One of the easiest swaps you can make for a major health boost is ditching refined flour in favor of whole wheat or maybe not. Just because something is low in its calorie content does not mean that it's healthy. White bread has been invalidated by health campaigners and nutritionists but it actually is an important source of vitamins and minerals, new studies claim. Earlier nutritionists believed that consumption of white bread led to erratic blood-sugar levels, "Since it's low in fiber and protein that helps slow digestion, white bread is digested and absorbed rapidly. This leads to blood sugars rising quickly," says Palinski-Wade , the lead researcher. The researchers have found that the response seems to vary person to person, and that some people don't have a bad glycemic response to white bread.

A research team from the Weizmann Institute of Science in Israel recruited 20 healthy participants who normally ate 10 percent of their daily calories from bread, with both groups upping their bread consumption to about 25 percent of their calories. Each volunteer spent a week eating white bread and a separate week eating artisanal sourdough-leavened whole wheat bread. They ate bread first thing in the morning. Half the time, they were allowed butter on their bread. They couldn't eat anything else beginning the night before, and then for two hours after eating the bread. They also weren't allowed to exercise for two hours after eating, because all of these things can alter the glycemic response. After a week on their high-bread diets, the participants took a two-week break, then swapped onto the other kind of bread for a week. Throughout the study period, researchers monitored the participants' levels of glucose, calcium, iron, magnesium, fat and cholesterol, as well as their kidney and liver enzymes, and markers for inflammation.

They also kept a watch on the participants' gut microbiomes the trillions of bacteria and other microscopic critters inhabiting their intestines, believed to have a profound impact on overall health. Across the groups, the researchers found a similar response to the breads when averaged together. There were no significant overall difference based solely on the bread and glycemic response. The researchers also said there didn't seem to be a difference in the gut microbiota based on which bread was eaten.

This study challenged the common belief that types of food that are considered healthy are indeed healthy. It emphasized on the fact that people are different in their genetic makeup and lifestyle, and people have rather stable and person-specific microbiomes. "Our study suggests that, in terms of glycemic responses, different people respond differently to even the same meal, and in the context of white bread, this means that some people respond badly to white bread and should probably avoid it, while others have a healthy response to it, given what we measured "explained study author Eran Segal. "In a broader sense, what this means is that the 'one-size-fits-all' diets that are given to the population as a whole, without personalization, are probably not optimal for everyone," added study co-author Dr. Eran Elinav.

The researchers theorized that differences in the gut microbiome (the natural bacteria living in a person's intestine) may explain why people respond differently to different breads. The researchers added that they were able to predict what a person's glycemic response would be to a particular bread based on the makeup of their microbiome.

At least one nutritionist wasn't convinced that people should give up on whole grains. "This small, short-term study does not offer a free pass to eating tons of highly processed white bread, Epidemiological research has shown that people who eat more whole grains, such as whole grain breads, crackers, cereals, brown rice and quinoa, have a reduced risk of type 2 diabetes, heart disease, inflammation, obesity and certain cancers" said Heller, a senior clinical nutritionist from New York University Langone Medical Center. The scientists noted that more research needs to be done. Funding for the study came from the Israeli Ministry of Science, Technology and Space, as well as from private foundations and donors. In the meantime, a number of groups recommend eating whole grain foods instead of processed white foods. These groups include the U.S. federal government, the American Heart Association, the American Cancer Society, the American Diabetes Association and the Academy of Nutrition and Dietetics.

(With inputs from ANI)