Figures released on Friday show that inflation in Japan slowed down last month. But the price of rice, which is in short supply, rose at the fastest rate in 49 years.
The internal affairs ministry says the consumer price index, excluding fresh food, was 2.4 percent higher in September than a year earlier.
That compares with a rate of 2.8 percent in August.
Government subsidies for electricity and gas fees contributed to slowing cost-of-living increases.
Meanwhile, price increases of non-perishable food accelerated to 3.1 percent. The price of rice surged 44.7 percent year-on-year, the highest rate since September 1975. Chocolate rose 9.8 percent and domestically-produced pork 6.7 percent.
The ministry says higher costs of materials and transportation are driving prices of more food items up.