Consumer groups say the price rises are due to middlemen, while farmers' earnings stay the same, activists said at protests in Rome, Milan and Palermo.
"Pasta, bread, milk - these are the most important things. We are not protesting for perfumes or jewels," said, Marisa, at a Rome protest.
Campaigners have called on the government to intervene to stop the price rise.
Clemente Mastella, the Italian justice minister, had promised to support the cause by skipping his favourite Neapolitan dish of pasta tubes stuffed with tomatoes and ricotta cheese.
But there were few signs of his compatriots making a similar sacrifice at lunchtime, with hungry workers eating their usual pasta dishes at Rome restaurants that ignored the boycott.
Carlo Pileri, of the ADOC consumer group, said: "The pasta strike is symbolic, a call for Italians to make a sacrifice - to sacrifice something we can't give up, even when we travel abroad."
Corporate hike
Increasing demand from Egypt to India and weather damage to global crops have driven up prices in by about 80 per cent this year in the US.
Users including Kellogg, the biggest US cereal maker, General Mills Inc, Sara Lee Corp and PT Indofood Sukses Makmur, the world's biggest producer of instant noodles, are responding by raising prices, fuelling inflation.
Javier Blas, an FT commodities correspondent, told Al Jazeera that a rise in global population was also responsible for an increase in demand.
Australia, which is forecasted to be the world's second-largest exporter of wheat next year at 15 million tons, produced just 9.9 million tons last year after drought devastated the crop.
Dry weather has again diminished crop prospects this year.
Egypt, the world's second-biggest importer of wheat behind Brazil, today bought 27,000 metric tons of the grain after saying yesterday it sought at least 55,000 tons, according to two traders involved in the tender.