As you browse the shelves of many stores, you can see a growing consumer interest in probiotics that goes far beyond yogurt. Probiotics are present in many food supplements. They can now be found in toothpastes, skin care products and snacks for humans and pets. They even enter into the composition of certain anti-allergic mattresses. The craze for probiotics is explained by the increasing attention paid by scientists to our intestinal microbiome (the set of bacteria that live in our large intestine) and by the recognition of its importance.
Researchers are studying the gut microbiome for its potential to benefit countless aspects of physical and mental health. This potential is generating excitement about improving our health, and possibly stemming the obesity epidemic, by improving our gut bacteria. The possibilities are such that researchers are now pushing the medical community to consider the gut microbiome almost as an organ in its own right.
Like any other organ, the gut microbiome has the ability to make us sick if we don’t maintain it properly. Conversely, it has the power to promote health and well-being if we take care of it properly. We know that the human microbiome is crucial in healthy physiological processes. Research shows that it plays many and varied roles. For example, in the normal development of the immune system, in the mediation of inflammatory pathways and metabolic processes, and in the regulation of appetite.
A recent, high-quality, high-profile study in Nature Medicine, for example, documents significant new connections between health and gut bacteria, linking certain microbes to healthy and unhealthy outcomes. Certain bacterial species seem to be linked to less appetite, lower body weight and reduced general inflammatory state. Recent research from Warwick Medical School has shown that other bacterial species are associated with unfavorable metabolic status. Additionally, scientists have recently linked a certain microbiome pattern to healthier aging. To date, research has only identified about 1,000 of the millions of microorganisms we think are present in the human body.
By age 3, the gut microbiota is established, but we know that various factors can alter its diversity and development. These factors include host genetics, diet, age, mode of birth, and antibiotics, as well as probiotics, fecal microbiota transplants, and prebiotics.
Contents
Super health effects or super advertising promotion: the science decides
In a time of increased scientific research and growing public interest, marketers are selling a lot of products based on unproven promises. To sort out advertising claims and analyze the benefits of the array of items on the shelf, we need to distinguish between fads and facts. Here’s what the latest science tells us.
Probiotics
Scientists believe that probiotics work by maintaining the balance of normal gut microbiota and enhancing the immune system. Recent research suggests that certain types of probiotics may have a beneficial effect on specific diseases.
Fecal transplants
Recent work has examined the benefits of transplanting faecal bacteria from healthy donors into people with gut diseases, with the goal of restoring healthy gut microbiota function. These transplants can treat various diseases, including inflammatory bowel disease, irritable bowel syndrome, constipation, metabolic diseases, autoimmune diseases, allergic disorders, and chronic fatigue syndrome. These procedures are much more effective than probiotics. The effects of transplants on the microbiota last about 24 weeks, compared to 14 days for probiotics.
Prebiotics
Plant-based foods are a source of prebiotics, which stimulate the growth of gut bacteria. Research has shown that prebiotics exhibit three characteristics:
– They resist absorption in the digestive tract.
– The microbiome can ferment them.
-They can have a positive effect on health through a direct or indirect action of the microbiome.
Dietary fiber, mainly from plant foods, is the main source of prebiotics. Dietary fiber can be classified into two categories: soluble fiber, which helps reduce cholesterol and glucose levels, and insoluble fiber, which promotes the passage of materials through the digestive system. The main sources of soluble fiber are fruits and vegetables. Although cereals and whole-grain products provide insoluble fiber, most high-fiber foods contain both types of fiber.
Current recommendations from most European countries for dietary fiber intake for adults are 30-35 grams per day (g/day) for men and 25-32 g/day for women, but diet most people’s diet does not meet these values. Most of us should increase our dietary fiber intake by about 50%.
The health benefits of dietary fiber are widely recognized. They reduce countless health problems, including excess weight, chronic inflammation, depression, and the risk of cardiovascular disease and colorectal cancer. Importantly, this work also highlights the beneficial effect of dietary fiber on the human microbiome.
Insights into the broader role of the microbiome in overall human physical and mental health are on the horizon. In the meantime, the take-home message for the general public remains simple:
Eat lots of fiber. Eat a variety of unprocessed foods. Eat fruits and vegetables. You will have better metabolic health, as well as a more diverse gut microbiome.
Sources
Modification of fecal microbiota as a mediator of effective weight loss and metabolic benefits following bariatric surgery
Microbiome connections with host metabolism and habitual diet from 1,098 deeply phenotyped individuals
Modification of fecal microbiota as a mediator of effective weight loss and metabolic benefits following bariatric surgery
Strain-Specificity and Disease-Specificity of Probiotic Efficacy: A Systematic Review and Meta-Analysis
Understanding the mechanisms of faecal microbiota transplantation
Impact of prebiotics on immune response: from the bench to the clinic
The Health Benefits of Dietary Fiber
Activation in vagal afferents and central autonomic pathways: early responses to intestinal infection with Campylobacter jejuni
[HighProtein-Foods.com]
