With the numbers of elderly increasing rapidly, it is important for both individuals and society that the oldest old maintains autonomy. To know how to attain successful aging, we investigate the status of centenarians. The characteristics of centenarians in Tokyo is 1) low level of nutritional parameters, 2) low level of cholesterol and HDL-cholesterol, 3) low level of red blood cells and hemoglobin, 4) high level of CRP, 5) high level of homocysteine, 6) high level of von Willbrand factor. The incidence of dementia is 59.3%. Are these characteristics due to aging itself or other factors? We examined the effect of nutritional status, inflammation and level of homocysteine on the characteristics. The level of albumin is associated with serum level of lipid, RBC, ADL and cognitive function. The level of CRP is related to the level of albumin, suggesting that inflammation is related to nutritional status. The level of homocysteine is associated with the level of von Willbrand factor, suggesting that homocysteine is related to endothelial injury. From these data, we propose the hypothesis that proinflammatory status is associated with aging, resulting in a part of characteristics of centenarians. Homocysteine is partly responsible for endothelial injury. Intervention to suppress proinflammatory status and homocysteine level may promote QOL in the oldest old.