Extreme Longevity notes an Italian study: "Sardinia [is] especially rich in male centenarians. The present study was undertaken to quantify and determine which particular lifestyle and nutritional variables endemic to Sardinia males accounted for their extreme longevity. The authors point out that no genetic differences have been found between Sardinian males and less long-lived males found elsewhere in Italy so they reasoned lifestyle choices were more likely causative of their longevity than genetic factors. The researchers specifically compared the frequency of several dietary choices and lifestyle factors between men of Sardinia and Italian men not from Sardinia. It was particularly surprising that diet alone didn't account for the differences. The frequency of meat, cheese, wine, grain and nut consumption was identical in the two groups. Total daily caloric intake was slightly but insignificantly lower in the Sardinian men. The most significant difference found was in the distance to work and average slope of the terrain between the men of Sardinia and those from other regions. The researchers conclude it is likely the large amount of daily physical exercise required to walk long distances up steep mountain climbs that has led to the increased longevity of Sardinian males. They point out the effect of physical exercise on extending longevity is becoming widely recognized, appearing at the conclusion of many scientific articles."