Most people don’t think much about parasites. But in postwar Japan, Mokichi Okada saw this as one of the most urgent health problems of his time — and he believed the cause was hiding in plain sight.
A Problem Hiding in the Soil
What goes into the soil eventually enters the body. Natural farming starts by keeping the soil clean.
In the early 1950s, studies showed that over 80 percent of Japanese people carried roundworms. For most, the symptoms were mild. But for some, the infection was severe — dozens, even hundreds of worms affecting internal organs, causing serious pain and, in some cases, death.
The medical explanation of the time pointed to human waste used as fertilizer. Parasite eggs in the soil would pass into vegetables, then into the body. That much, Okada agreed with.
But he went further.
What Medicine Hadn’t Explained Yet
Okada observed that other parasites — pinworms, hookworms, scabies, athlete’s foot — couldn’t be fully explained by infection alone. Medicine at the time labeled many of these “cause unknown.”
His conclusion was this: when the blood is clouded by what enters the body — particularly impure substances used in farming — the body’s internal environment becomes one where parasites can take hold.
The solution, he argued, was not more medicine. It was cleaner inputs from the start.
What the Body Actually Needs
Okada believed the human body, when given the right conditions, is naturally resistant to parasites and disease. Those conditions are simple: fresh air, clean water, and food grown from soil free of impure additives.
He also suggested that unnecessary medicines and chemical substances, introduced into the body as foreign materials, work against this natural balance rather than supporting it.
In his view, a person who eats food grown from truly clean soil — without chemical fertilizers or human waste — could live in good health well into old age. One hundred years, he said, was not out of reach.
Read the Original
This is a short introduction. The full text — written by Okada in Japanese in 1951 — is available on meshiya.jp.