Obesity, metabolic syndrome and type 2 diabetes, what are the causes? Recent scientific research shows that, more than fat, it is sugar that destroys the intestinal microbiota and all our protection against weight gain and the increase of the waistline and blood sugar. Sometimes, however, eliminating or reducing sugar is not enough to see the benefits and counteract obesity and diabetes. What to do in these cases? The research we are talking about today also offers an answer to this question. The study was published a few days ago in the journal Cell by a Japanese team (Kawano et al, Cell, 2022).
Diet, obesity and diabetes
A Western-style diet rich in sugar, fat and processed foods paves the way for obesity, metabolic syndrome and diabetes. However, to date, it has not yet been possible to understand the mechanisms triggered by the unbalanced diet to reach these conditions. The research we are talking about today, on the other hand, sheds light on this aspect.
The sugar problem, the study
Scientists have conducted a laboratory study on a population of mice. The mice were fed a Western-style diet, therefore rich in fat and sugar, for 4 weeks. At the end of the 4 weeks, all the mice showed symptoms of the metabolic syndrome, such as weight gain, insulin resistance and glucose intolerance. Not only that, the intestinal microbiota of mice, which is the set of bacteria that populate the intestine, also showed important changes. In particular, the scientists were able to notice a reduction in those bacteria associated with the presence of particular cells of the immune system responsible for reducing the absorption of lipids in the intestine and inflammation. In other words, these cells have the task of keeping the intestine healthy and protecting the body from the absorption of potentially harmful lipids. Well, the cause of these changes was sugar, which eliminated the beneficial bacteria. It is worth noting that, by eliminating sugar but giving the mice a diet rich in fat, most of them kept the beneficial bacteria and cells of the immune system capable of combating obesity and diabetes in the intestine. And in fact, these mice did not develop diabetes and obesity, despite the fact that they ingested the same calories as the mice who had a diet rich in fat and sugar and who had gained weight and developed insulin resistance.
Sometimes removing sugar is not enough
So, surely a first step to gain health is to reduce sugar. In this way we can protect the intestine and our natural defenses against obesity, diabetes and metabolic syndrome. However, research has shown that eliminating or reducing sugar has not always led to beneficial results. In fact, some mice continued to gain weight and develop diabetes, despite the elimination of sugar. The point is, some mice were already starting at a disadvantage with a microbiota that lacked the beneficial bacteria. The elimination of sugar did not allow these bacteria to reform. The intake of probiotics, on the other hand, restored the intestinal flora and the defenses against weight gain and blood sugar.
The research, as the study authors themselves state, applies not only to mice but also to humans. What emerges is that, to combat obesity, metabolic syndrome and diabetes, the main intervention is always to eliminate, or at least reduce, sugar. However, this does not work in all cases, when the microbiota is highly unbalanced. To protect ourselves from overweight and diabetes, it is therefore always important to take care of our intestinal microbiota, taking probiotics, which are found in pharmacies or in yogurts or drinks that indicate it on the label, and prebiotics, which feed good bacteria. Prebiotics are, for example, asparagus, garlic, chicory, onion, Jerusalem artichoke, chia seeds, flax seeds, almonds, artichokes, oats, barley and legumes.