[ad_1]
- Dietary fiber may help prevent cardiovascular disease, type 2 diabetes, and obesity through its effects on the gut microbiota, which is the community of microorganisms that live in the gut.
- However, typical Western diets lack the fiber these friendly microbes need to thrive.
- Experiments in mice and humans suggest that snack foods supplemented with particular types of fiber can alter the gut microbiota and cause widespread physiological effects.
- It would be possible to source fiber for future prebiotic snacks from food industry waste, such as peels, rinds and husks, which manufacturers would otherwise reject.
The bacteria, archabacteria, viruses and fungi that live in the human intestine – collectively known as intestinal microbiota – have a profound effect on the physique and mental well-being.
Research suggests that by nurturing beneficial members of this community, dietary plant fiber can help prevent chronic health problems, such as heart disease, Type 2 diabetes, and
However, Western-style diets are often high in fat and deficient in these plant fibers.
The idea of supplementing otherwise unhealthy snacks, such as cookies and crisps, with fiber may seem simple, but the relationship between diet, the microbiota and individual health is very complex.
Scientists at the Center for Gut Microbiome and Nutrition Research at the Washington University School of Medicine in St. Louis, MO, are studying this relationship with a view to developing prebiotic snack products.
In previous job, they identified sources of fiber that are not only cheap and readily available, such as the peels, rinds, and husks typically discarded, but also stimulate gut microbes that obese adults tend to lack.
In their new research, which appears in
“As snacks are an integral part of Western diets, we are working to help develop a new generation of snack formulations that people will love to eat and that will support a healthy gut microbiome that affects many aspects of well-being,” explains Dr. main author. Prof. Jeffrey I. Gordon, MD, who runs the Edison Family Center for Genome Sciences & Systems Biology at Washington University School of Medicine.
The snack maker Mondelēz International, which owns brands such as belVita, Cadbury and Oreo, partially funded the work.
In the first phase of their research, the scientists used “gnotobiotic” mice, which are reared under sterile conditions so that they are devoid of gut microbes.
They colonized the intestines of these mice with microbes from obese people, then fed the animals the type of high-fat, low-fiber diet associated with overweight and obesity.
Then, they successively introduced snacks into the diet of the mice, supplemented with pea fiber, orange fiber or barley bran. Between each type of snack, there were withdrawal periods during which the mice ate only the high-fat, low-fiber diet.
This approach allowed researchers to track the effects of each type of fiber on the animal’s gut microbiota gene pool, which they did through analyzes of microbial DNA in fecal samples.
They found that each snack resulted in an increase in the abundance of genes needed to make enzymes to digest that particular fiber. Presumably, this is because the fiber has given bacteria with the right genes a competitive edge over others.
In the second phase of the research, the researchers conducted similar experiments involving 12 overweight or obese human volunteers.
To avoid any changes resulting from differences in their diets, the volunteers followed a strictly controlled diet high in saturated fat and low in fiber.
The researchers then monitored genetic changes in their microbiota before, during and after a 2-week period, during which they also ate snack bars fortified with pea fiber.
The team observed similar changes in the gut microbiota of volunteers to those they saw in mice, with an increased abundance of genes needed to digest this fiber.
Finally, the scientists investigated whether consuming snacks containing several different types of fiber would lead to greater changes in the microbiota than consuming pea fiber alone.
A group of 14 volunteers first ate a snack containing a combination of two fibers: pea fiber and inulin, which occurs naturally in onions, bananas, asparagus, artichokes and chicory root. Later, after a period of withdrawal, they ate a snack containing four fibers: inulin, pea fiber, orange fiber, and barley bran.
This part of the study showed that the more types of fiber there are in the diet, the more abundance of bacterial genes that play a role in fiber metabolism.
These genetic changes were closely correlated with changes in blood protein levels that contribute to a wide range of key physiological processes.
For example, there have been significant changes in the levels of proteins involved in glucose metabolism, immunity, blood clotting, blood vessel function, and bone and nerve cell biology.
Overall, the experiments reveal how responsive the gut microbiota is to changes in dietary fiber, even in people who are used to low-fiber diets.
“In principle, fiber can be incorporated into a variety of snack formats familiar to consumers – chips, bars, cookies, etc.,” Professor Gordon said. Medical News Today.
One of the limitations of the study was that the volunteers followed a strictly controlled diet in addition to the fiber-fortified snacks. In the real world, diets are much more complicated.
However, researchers are already investigating whether their preliminary results hold up when people can eat what they like.
“The follow-up studies involve administering the prototype snacks to participants who are consuming their normal diet,” said Professor Gordon.
“This approach may provide information on the robustness of effects and dose dependence of fiber-based snack formulations on the gut microbiome and host physiology in more realistic consumption settings,” he said. he adds.
The study identified protein biomarkers of possible physiological changes in the participants’ blood. However, it is currently unknown whether such changes would reflect real health benefits.
Only clinical trials can reveal whether such snacks can help prevent type 2 diabetes or obesity, for example.
In one
“[These] the results provide valuable mechanistic information on microbial contributions to human dietary responses. This will likely lead to long-term randomized clinical trials that assess causal links between distinct food ingredients, microbiome modulation, and downstream health-related outcomes for humans. “
|
Sources 2/ https://www.medicalnewstoday.com/articles/could-prebiotic-snacks-boost-healthy-gut-bacteria-in-obesity The mention sources can contact us to remove/changing this article |
[ad_2]