People Who Live Past 100 Years Share One Thing In Common

Revealed by a strange new experiment.

Younes Henni, PhD
4 min readOct 6, 2021
Image by ThuyHaBich from Pixabay.

John Cryan couldn’t believe his eyes. The mouse was getting younger!

Old and failing before the trials, the animal’s brain was rejuvenating significantly. The old mouse can now remember and learn much like any of its younger peers.

Alongside Ted Dinan (his friend and mentor), Cryan spent two decades researching longevity. This was the breakthrough they waited for.

Could this work on humans? Too soon to speculate. The human brain is far more complex than mice’s. And the procedure in itself is … a bit weird, to say the least.

To reverse the mouse age, Cryan and Dinan transferred faeces (poop) from a younger mouse into the bowels of the old one. Their goal was for the alien faeces to completely alter the bacteria in the old mouse’s bowels.

Even before their results, mounting evidence suggested the gut-to-brain connection was critical for longevity. And this is true whether we’re talking about mice, humans, or various other animals.

People who live more than a hundred years share one thing in common: diverse gut bacteria that are highly effective in fighting disease and breaking fats and sugar.

Good gut bacteria strengthens the walls of the bowels. Thicker gut walls protect your body from microbes that can spill from the gut into the bloodstream. If this happens, the heart will pump all these harmful microbes to your organ. As a result, your risk of diabetes, heart disease, cancer, Parkinson’s, Alzheimer’s, and dementia skyrockets.

On top of this, good gut bacteria help your brain produce more dopamine and serotonin. As a result, your mood gets better. So not only it enables you to live longer, but good gut bacteria make you happier.

Faeces transfer might shock or even repulse you. But it’s already an established treatment for patients with severe bowel infections. The procedure even has a name: FMT (Fecal Microbial Transplantation). With a success rate of 90%, FMT is more effective in curing bowel infections than any known antibiotics.

The results of Cryan and Dinan experiments suggest FMT can even alter the brain functions of the host, making it younger. Thrilled with the prospects of such experiments, other labs went a few steps further.

First, scientists tested FMT on more animals. Faeces were transferred from young worms to old worms, young flies to old flies, and young fish to old fish. The results were equally spectacular: all these creatures started getting younger. Then, scientists inverted the procedure. They transferred faeces from old animals into young ones. Verdict? The young animals’ brains declined rapidly.

Another experiment achieved something even more intriguing. This time, scientists took human faeces from people with depression and injected them into healthy mice. Lo and behold, the mice developed depression-like symptoms.

Will manipulating our gut bacteria with human faeces or even animals faeces make us live longer? “We still lack cause-and-effect studies in humans,” admits Cryan. After all, not all animal studies translate to humans. Besides, many would recoil at the prospect of FMT, even if it might add to their lifespans.

Still, the gut-to-brain connection is undeniable. And good gut bacteria is crucial in slowing the ageing process.

While eternal-life-by-FMT clinics are not opening anytime soon, keeping a healthy gut is simpler than you think. Your diet, among other things, can promote or disrupt good gut bacteria. “I have become much more aware of the amount of fibre I take, especially plant fibres,” admits Cryan.

Here are a few tips to promote a healthier gut.

  • Eat plenty of fibre-rich vegetables, such as artichokes, asparagus, lentils and onions. Fibre promotes good gut bacteria and strengthens the gut walls. As a result, microbes will struggle to escape into the body.
  • Eat fermented food. This includes yoghurt, kefir, sauerkraut, kimchi, kombucha and pickles. Fermented food is high in natural microbes that help fight pathogens. Avoid pasteurised fermented food. That one lost all its good bacteria.
  • Take probiotics. These microbe-rich supplements help restore the natural balance of your gut bacteria. Even though they’re not classified as medicine, speak to your doctor beforehand.
  • Aside from diet and supplements, a good night’s sleep, low stress, regular exercise and hydration are crucial to keeping your gut healthy.

“All disease begins in the gut.”–Hippocrates of Kos (460 BCE)

Even before you were born, your gut bacteria was growing. As a fetus, you’ve already been loading from the bacteria and fungi swimming in the uterus. Once you were born, your environment, the breast milk you had, and the food you ate shaped your gut bacteria.

Think more about how to set your gut bacteria the right way. Not only you can add decades to your life, but you can live healthier and happier too. As a grown-up, the choice is now in your hands.

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Younes Henni, PhD

Physicist • Soft Dev • ☕ Junkie • I bring you the latest in science, tech, health, economics & personal growth. To read all: