Do you want to take care of your microbiota without embarking on a complicated diet? In the show “Ca va much better” on RTL, broadcast on August 11, 2026, Violette Babocsay, dietician and author of Great Guide to Nutrition and Weight Loss (Marabout), offers a simple path: vary the plants more during the week.
The microbiota matters, but it does not decide weight alone
The intestinal microbiota refers to all the microorganisms that live in our digestive tract. Violette Babocsay recalls that it participates in particular in digestion, the functioning of the immune system and metabolism. She also emphasizes that it communicates with the brain, which explains the interest of research in the gut-brain axis, without this transforming the microbiota into the sole explanation of all diseases.
To better understand the role of the intestinal microbiota, we must keep one idea in mind: it is an important player, not a magic button that just needs to be pressed.
This is especially true for weight. The dietitian cites a known experiment carried out in mice: when the microbiota of obese mice is transferred to thin mice, the recipient mice gain weight. But, she insists,
the results observed in mice do not automatically translate to humans.
The fact check points in this direction. In humans, microbiota transplantation trials, notably the FMT-TRIM pilot published in PLOS Medicinemainly studied thin donors towards people with obesity or metabolic syndrome. They did not show a robust effect on weight loss. Clearly, the microbiota can intervene in metabolic balances, but it does not alone explain the differences in weight between individuals. Weight also depends on many biological, social, environmental and behavioral factors.
The 30 plant rule is a guideline, not an obligation
Violette Babocsay’s central advice concerns dietary diversity. A diverse microbiota is often considered a favorable indicator, even if the notion of a “healthy” microbiota is not reduced to a simple diversity score.
The dietician cites the American Gut Project: people reporting consuming more than 30 types of plants per week had a different and more diverse microbiota than those consuming 10 or fewer. Key point: this is an observational association, not proof that this threshold directly causes better health.
This figure therefore remains useful if it is taken as a flexible guide to expand your food repertoireand not as a rule to absolutely succeed. Plants are not limited to vegetables: fruits, pulses, cereals, seeds, nuts and herbs can also count, provided they are really different.
Violette Babocsay gives very concrete examples: a muesli can contain several plants if it contains oat flakes and a mixture of distinct seeds; a ratatouille can add about five depending on the recipe; varying cereals, instead of always eating wheat or wheat pasta, also increases diversity.
How to add plant diversity without changing everything
The point of this benchmark is to start from what we already eat. No need to disrupt all your meals: gradually increasing variety is often more realisticespecially if you are not used to consuming a lot of fiber.
A few simple ways to increase the count throughout the week:
- Alternate cereals: oats, brown rice, buckwheat, quinoa, barley or rye according to your habits;
- Add a small amount of different seeds in yogurt, muesli or salad;
- Provide a portion of legumes : lentils, chickpeas, red beans or split peas;
- Vary nuts : unsalted walnuts, almonds, hazelnuts or pistachios;
- Change the accompanying vegetables rather than always repeating the same things;
- Use different herbs and aromatics
when they fit naturally into the dish.
This diversity can also help you gradually increase your fiber intake. According to the recommendations of Public Health France, plant foods rich in fiber are associated, at the population level, with a reduction in the risk of several chronic diseases, notably cardiovascular and metabolic. Here again, this is not an individual promise, but an additional argument to diversify the plate.
If you are following a medically prescribed diet, have a chronic digestive disease, irritable bowel syndrome, food allergies, kidney failure or specific restrictions, it is best to seek medical or dietary advice before greatly increasing plants or fiber. For others, the simplest thing is to look at the week as a whole: adding a new seed, a legume or a different cereal already counts.
The microbiota is therefore neither a magic wand nor a designated weight culprit. But the rule of 30 plants can serve as a practical compass: it helps to better understand the links between intestinal microbiota and weight gain without exaggerating them, while making meals more varied.