TOKYO (BLOOMBERG) – Russian missiles pounding Ukraine have spooked Japan into boosting defence spending. Now, with tensions rising over the Taiwan Strait, calls are growing to address another security threat: shrivelling rice paddies.

For decades, Japanese consumers have been eating less rice and fish in favour of more bread, meat and edible oil, leading the country’s calorie-based food self-sufficiency ratio to slump to 37 per cent in 2020 from 73 per cent in 1965 – the lowest among major economies.

Professor Toshiyuki Ito, retired vice-admiral for Japan’s Maritime Self-Defence Force, said the government’s abandonment of rice paddies and other agricultural land is leaving the country more vulnerable than ever.

“They don’t do anything for national security,” Prof Ito, who now works at the Kanazawa Institute of Technology, said about Japan’s ministries responsible for food production. “They think only about economic efficiency.”

The impact of higher global grain prices, fertiliser shortages and fuel inflation, exacerbated by a weaker yen, have already been filtering through to Japanese consumers in recent months, with supermarkets marking up everything, from instant ramen noodles to ice cream. But any major blockade or disruption to sea lanes around China and the Taiwan Strait could have bigger implications than just price inflation.

‘If you don’t have food, you can’t fight’

Unlike the United States and European Union, Japan would have little to fall back on in the event food imports were to dry up. To ensure the country’s national security, it’s crucial for Japan to increase the amount of rice and wheat grown domestically, according to Professor Nobuhiro Suzuki, who teaches agricultural economics at the University of Tokyo.

“In terms of national security, food should come before weapons,” he said. “If you don’t have food, you can’t fight.”

Japan’s shift away from a rice-dominated diet was driven in part by higher per capita income. An expansion in global trade ushered in more imported foods, while exposure to travel and television encouraged more diverse eating habits.

The growing ranks of working women and single people also brought about lifestyle changes and the embrace of fast food – the country boasts the third-largest number of McDonald’s outlets after the US and China.

Per-capita seafood consumption has fallen to under 25kg a year from over 40kg two decades ago, and those who choose fish are increasingly opting for fattier imports, such as mackerel and salmon from Norway and Chile, according to government data.

Another major factor behind the decline in the self-sufficiency ratio has been Japan’s near-total dependency on imported grains for animal feed. That means most domestically raised beef is not counted in self-sufficiency calculations.

The increased reliance on imports worries former agriculture minister Hiroshi Moriyama. In June, he led a group of ruling Liberal Democratic Party lawmakers that submitted a report to Prime Minister Fumio Kishida, calling for more government action on food security.

“Through the Ukraine situation, we’ve realised that what you can do domestically, you should,” he said in an interview. “You have to produce as much as you can at home, including fertilisers and seeds.”