When we cook our slow-cooked carrot soup, we’re not doing anything inventive. Carrots, water, a few slices of ginger, a pinch of salt, and two hours over a flame so gentle the surface barely breathes. The recipe would fit on the back of a matchbox.
More than a century ago, pediatrician Ernst Moro had almost the very same method down on paper. And with it, he saved thousands of children.
The doctor who left behind a reflex
Ernst Moro was born in 1874 in Ljubljana. He studied medicine in Graz, worked as a children’s doctor in Graz, Vienna, and Munich, and in 1911 took over the children’s clinic in Heidelberg, where he later also taught pediatrics as a professor. Anyone who has ever held a newborn knows his name today: the Moro reflex is that short, sudden reaction when a startled baby flings out its arms and legs and then, after a few seconds, pulls them back in. It shows up right after birth and fades around the fourth or fifth month.
But pediatrics was a field still in diapers back then, and Moro was grappling with a far harder problem than naming reflexes. Children were dying of diarrhea. Not of anything exotic — of ordinary intestinal infections, with infant mortality, according to records of the time, running at around twenty-five to thirty percent. There were no antibiotics. No intravenous therapy as we know it today, either.
A recipe that looks like a mistake
Around 1908, while still a doctor at the Munich children’s clinic, Moro reached for something that looked nothing like medicine. He drew on old home remedies that housewives had known long before him, and wrote them down as a prescription:
Boil half a kilo of carrots until soft. Strain, top up with water to one liter. Season with salt.
— Moro’s prescription, loosely retold
That’s all. No spices, no fat, nothing extra. This soup lowered mortality and complications in children with diarrheal illness so dramatically that it became standard in German-speaking countries — Morosche Karottensuppe was cooked in hospitals and at home for decades.
And nobody really knew why. People knew it worked. The explanation was missing for almost a hundred years.
The answer came in 2002
It wasn’t until 2002 that a paper finally explained it — and its title was exactly as dull as it should be: Acidic oligosaccharides as the active principle of aqueous carrot preparations in the prevention and treatment of gastrointestinal infections.
The core of it is surprisingly easy to picture. During long cooking, short sugar chains split off from the carrot fiber — acidic oligosaccharides. In shape they closely resemble the spots on the intestinal wall where harmful bacteria normally latch on. The bacterium mistakes them for its target, attaches to them — and leaves the body, because it no longer has any way to grab hold of the real intestinal wall.
So it isn’t killing anything. It’s a wrong address.
And here’s the part that most often gets lost in the retelling: those chains don’t appear in carrots on their own. Raw carrots won’t give them to you, and simply boiling them until tender isn’t enough either. They only form during long, slow cooking. The active ingredient in that soup isn’t the carrot. It’s time.
What it leaves us
Over time, Moro’s soup was pushed aside by antibiotics and pills; today diarrhea is treated mainly with rehydration and probiotics. No one needs to boil carrots for two hours when something faster and more effective is right there at the pharmacy.
So let’s say it plainly, so there’s no confusion: our soup is not medicine. If a child is sick, that’s a matter for a doctor, not a soup pot. Nothing we cook replaces medical treatment.
But something else remains, and that interests us far more. That you can draw the most out of a few ordinary ingredients if you give them enough time. That slow isn’t a style or a marketing word — it’s a technical step that changes what’s in the pot. We learned exactly the same thing with sourdough and with broths. Moro knew it more than a hundred years ago — he just didn’t yet know why.
Our carrot soup takes 1.5 kilograms of carrots, two liters of water, slices of fresh ginger, and at least a hundred and twenty minutes over the lowest flame. Thicker than Moro’s prescription, with ginger added and a few drops of oil and sesame on top when served — because we cook it as a meal, not as a prescription. We use as little salt as we possibly can. It doesn’t need it. And on the menu you’ll find it under the name it deserves: Dr. Moro’s Carrot Soup.
Recipe · From our kitchen
Dr. Moro's Carrot Soup
- Ingredients: 1.5 kg organic carrots, 2 l water, 30 g fresh ginger, a pinch of salt. Nothing else.
- Time: at least 120 minutes over a gentle flame — no hard boiling.
- Then: blend until smooth, adjust the consistency with water.
- You'll find the full method, with nutrition facts, in the recipe Dr. Moro's Carrot Soup.
This piece was prompted by the article Ernst Moro — the doctor who saved thousands of children with a simple carrot soup on Dobré noviny. We filled in the details about the year the recipe was created and the 2002 study from German sources.
