the crazy idea of ​​researchers from Clermont-Ferrand

Researchers from Clermont-Ferrand have designed a very special bread: thanks to a recipe enriched with fiber, it should, according to them, help fight obesity and pathologies such as diabetes.

In Clermont-Ferrand, researchers started from a worrying observation: globally, obesity has tripled since 1975. To fight against this disease, they created a very particular bread: a bread enriched with fermentable fibers (therefore degraded by our intestinal microbiota) potentially capable of increasing insulin sensitivity and therefore limiting the development of diabetes. This bread could be recommended for overweight people. “Dietary fiber is known to have a positive impact on health and in particular on obesity. It is particularly in wholemeal breads that we can find them. On the other hand, white bread, the most consumed, is characterized by its very high contribution of rapidly digesting carbohydrates which can contribute to promoting both obesity and diabetes. Adding fermentable fiber to white bread can therefore improve its nutritional characteristics.explains Isabelle Savary-Auzeloux, researcher at INRAE.

Dietary fiber is generally known to have a positive impact on health. This is the reason why the dietary recommendations are in the direction of increasing the proportion of fiber in the diet through the ingestion of fruits and vegetables, legumes and all foods rich in fiber. “We started from the observation that the problem we have in France, and we are not the only ones, is that we eat less fiber than what is recommended in our diet. We are ingesting 20 grams of fiber per day in our diet and we would need at least 30 or more if we really want proven health effects. Despite the campaigns that we see everywhere to increase the quantity of fruits and vegetables per day, we realize that ultimately it is not easy to change people’s eating habits.”, regrets Isabelle Savary-Auzeloux.

The idea was therefore to work on a food already widely consumed, which would present no difficulty in integrating into the daily diet. “In France, bread is a food that remains regularly consumed, even if we eat less and less of it. We say that if this bread could be a vector of dietary fiber, this could have a health effect. For the moment, we are at the research stage. It’s a bread that you won’t find in stores.”she specifies. Some people, either because they are obese or because they have insulin resistance problems, would benefit from consuming more fiber but have difficulty changing their eating habits.. “Using bread as a vector, a food that is generally very well consumed by everyone, is a way of providing additional fiber to populations who have difficulty switching to other foods”, adds the researcher.

In fact, no one has yet been able to taste this innovative bread. The first testers are little pigs: “We have not, in humans, done any studies with this bread. They were made on an animal which is the mini pig. Physiologically speaking and metabolically speaking, it is an animal close to humans, but we have not verified this effect in humans. We are very far ahead in terms of reflection.”

The first step was the design of the bread, enriched with a mixture of fermentable fibers on a basis of 20% inulin, 20% pectin and 60% resistant starch. “We say “fiber” because there is not one dietary fiber, that is to say a single type of chemical molecule that would be associated with this notion of fiber”indicates Isabelle Savary-Auzeloux. “It is a whole set of polysaccharides, that is to say sugars stuck to each other, more or less large in terms of size, which have the particularity of not being digested in the upper part of the intestine. like the rest of our food. While proteins, starch and lipids are digested higher, these fibers reach our colon, where we find our intestinal microbiota which will degrade them.

Some of these fibers will not be digested and therefore contribute to the increase in the size of stools. “These fibers are known to affect intestinal transit,” adds the researcher. If some will have a purely digestive effect, other fibers, those supplemented in this bread, are fibers which have the particularity of being more easily broken down by the micro-organisms in our colon. “This degradation will promote the production of molecules, particularly short-chain acids. They are known to, when absorbed into our body, have beneficial effects for some of them for our health and through this action contribute to limiting obesity and cardiovascular diseases in the broad sense.”

Eating fiber can also affect the speed of lipid absorption and limit it, thus helping to reduce our fat intake. “The effects of fiber are on several levels, both digestive and also metabolic via the action of molecules which are generated by the intestinal microbiota.”Increased fiber ingestion, particularly fermentable fiber, has shown, in controlled clinical studies, a beneficial effect on insulin sensitivity and therefore the reduction in the occurrence of diabetes and cardiovascular pathologies. “We assume the action of short-chain fatty acids (butyrate and propionate) known to limit diabetes and increase insulin sensitivity”specifies the researcher in an article published on the INRAE ​​website (National Research Institute for Agriculture, Food and the Environment).

If you want to benefit from the beneficial effects of fiber without waiting for the possible commercialization of this revolutionary bread, many foods contain it naturally: “We talk about fruits and vegetables, but another very interesting source of fiber which, unfortunately, generates very little interest currently, is legumes. They have the advantage of being very rich in protein, but also very rich in fiber”welcomes Isabelle Savary-Auzeloux. In fact, you should not expect to find this bread in supermarkets any time soon: “We are absolutely not considering marketing it. What we wanted was proof of concept by giving animals a quantity of bread that could normally be consumed by humans.” The mini pigs consumed 200 to 250 g, a quantity of bread that it is possible to consume during the day, according to the researcher.

For the moment, marketing seems complex: “These fibers have particular properties, which affect the bread-making process, which complicates the making of bread. If the thing were to be industrialized, you understand that machines cannot do certain things that we have been able to do in the laboratory We should check how much we can go up to in terms of percentage so that it remains both possible to be manufactured industrially and profitable…”

Despite all their virtues, dietary fiber can cause a certain number of discomforts, particularly intestinal. “To prevent people from giving up taking this type of product, you have to start slowly and then see if people accept it as part of, for example, a weight loss plan or a specific diet .” In addition, some people have difficulty assimilating these products: “We realize that, due to our very Westernized diet and the fact that we eat much less fiber, our microbiota has difficulty using it. Our microbiota is no longer used to seeing fibers and therefore it has adapted. It co-evolved with us and eventually no longer used them. The ecosystem of micro-organisms present in our intestine has adapted to this. Some people may have a particular microbiota that is non-responsive to the effect of fiber. Currently, there is no test that currently allows you to know to what extent you, as a person, might be a responder or a non-responder.”, regrets the researcher.

Eating bread enriched with fiber does not pose any health problems, apart from possible gastric discomfort which you must be vigilant about, but for healthy people, increasing the proportion of fiber in the diet is highly recommended.