You might recall that centenarian studies in the Ashkenazi population showed an association betweeen lipid metabolism and longevity. Here is another study that shows similar correlations in a different population: "Mechanisms underlying the variation in human life expectancy are largely unknown, but lipid metabolism and especially lipoprotein size was suggested to play an important role in longevity. We have performed comprehensive lipid phenotyping in the Leiden Longevity Study ... only LDL size and triglyceride levels were associated with offspring from long-lived families. Sex-specific backwards regression analysis revealed that LDL particle sizes were associated with male longevity. Triglyceride levels, but not LDL particle size, were associated with female longevity. Due to the analysis of a comprehensive lipid profile, we confirmed an important role of lipid metabolism in human longevity, with LDL size and triglyceride levels as major predicting factors." That different populations and the two genders have noticeable differences in the correlations between longevity and aspects of lipid metabolism is an indication of complexity: many factors at work under the hood.