Microbiota: the hidden world that drives your health

1. A miniature universe in your belly

Forget the sterile view of your body: it's home to a teeming galaxy of bacteria, viruses, and fungi. We talk about microbiota when they group together in communities: nose, mouth, skin, genitals... and especially the intestine. Together, these micro-inhabitants weigh up to 2 kg , or the weight of a large brain!

2. Focus on the intestinal microbiota

Nearly 80% of our microbes live in the digestive tract. Hundreds of species are found there, which together constitute a veritable metabolic organ: fermentation of fiber, production of vitamins, modulation of immunity... and more.

3. Bacteria: allies or enemies?

The term "bacteria" often brings to mind infections. In reality, most of them serve us well: each species has a specific talent, and diversity ensures the strength of the whole. The broader the range of species, the more effective the cooperation.

4. Balance, the key to healthy flora

When "good" bacteria decline, pathogens gain ground, or diversity drops, it's dysbiosis . Poor digestion, inflammation, metabolic disorders... the imbalance ends up having repercussions everywhere.

5. How modern life weakens our flora

Studies link the decline in bacterial diversity to the rise of diabetes, obesity, autoimmune and neuropsychiatric diseases.

6. Birth: first major encounter with microbes

The fetus is sterile. It all begins during childbirth:

• Vaginal route : the maternal flora (vaginal and fecal) inoculates the baby's intestine.

• Cesarean section : skin flora and hospital environment predominate.

Then, up to the age of 5, the ecosystem becomes more complex under the influence of diet (breast milk then solid foods), the living environment and even contact with animals.

7. Genetics vs. Environment: Who Wins?

Barely 10% of our microbiota is determined by DNA; the rest depends on lifestyle. Tellingly, unrelated roommates share a more similar flora than two members of the same family living separately. The good news is that our daily choices have a rapid impact, visible within just 24 hours of a dietary change.

8. The “superpowers” ​​of the microbiota

1. Vitamin Factory

   • B vitamins (energy)

   • Vitamin K (coagulation)

2. Manufacturer of short-chain fatty acids (SCFAs)

   • Slightly acidifies the colon: slows down pathogens

   • Nourishes intestinal cells

   • Strengthens the intestinal barrier

3. Immune shield

   • Occupies the land (“barrier” effect)

   • Starves out unwanted germs

   • Produces antimicrobial molecules

   • Trains white blood cells to distinguish friend from foe

4. Metabolic Conductor

   • Influences fat storage and the feeling of satiety

   • Intervenes in the regulation of blood sugar

5. Brain Messenger

   • Synthesizes neurotransmitters (95% of serotonin comes from the intestine)

   • Permanent dialogue via the gut-brain axis (impact on mood, stress, anxiety)

9. Feed your flora: the allies of the plate

• Fiber : vegetables, fruits, legumes, whole grains, seeds, nuts.

  Goal: 25g/day minimum.

• Polyphenols : red fruits, artichoke, cocoa ≥ 70%, green tea, spices (turmeric, cloves).

• Organic products : fewer pesticides, up to 70% more polyphenols.

• Fermented foods : yogurt, kefir, kombucha, miso, tempeh, raw sauerkraut, kimchi.

Quick tips

• Let the rice or potatoes cool: the resistant starch formed feeds the good bacteria.

• Vary the colors on your plate: each pigment feeds a different microbial group.

10. What sabotages the flora

1. Misused antibiotics

   • In children < 3 years, increased risk of allergies, obesity, inflammatory diseases.

2. Ultra-processed products

   • Additives (emulsifiers, sweeteners) = permeable intestinal barrier ➜ low-grade inflammation.

3. Sedentary lifestyle

   • Decline in AGCCs, loss of diversity.

   • Conversely, moving increases microbial richness… and the desire to move!

4. Chronic stress

   • Cortisol ↑ ➜ bacterial imbalance, sweet cravings, vicious inflammatory circle.

5. Sterilizing hygiene

   • Too little microbial contact = incomplete immune learning.

6. Insufficient sleep

   • Disrupted internal clock = disrupted microbiota ➜ breeding ground for metabolic diseases.

11. The 10 commandments of a happy microbiota

1. Let the kids get dirty : nature, animals, playing outside.

2. Reserve antibiotics for real infections .

3. Add some color to your plate with every meal.

4. Prefer homemade and raw products.

5. Choose whole grains over refined grains.

6. Invite legumes twice a week.

7. Sprinkle seeds and spices to boost fiber and polyphenols.

8. Move daily : walking, cycling, dancing, gardening.

9. Get 7-9 hours of sleep a night and turn off screens an hour before.

10. Pamper your mind : regular breaks, deep breathing, meditation.

To remember

Your microbiota is a malleable and powerful partner: by feeding it properly and respecting its rhythm, you simultaneously support digestion, immunity, metabolism, and mood. In short, taking care of your microbes is taking care of yourself!