Identification of a 'Blue Zone' in the Netherlands: a genetic, personal, socio-cultural, and environmental profile.

Abstract

'Blue Zones' (BZs) are regions with exceptionally high numbers of longevous inhabitants. Several factors have been suggested to promote longevity in BZs, but the evidence generally does not meet scientific quality criteria. We aimed to characterize a municipality as a 'relative BZ', satisfying three criteria: compared to other municipalities, more exceptionally longevous inhabitants, a higher life expectancy, and a more stable population. The population-based Longitudinal Aging Study Amsterdam is ongoing since 1992 in 11 municipalities across the Netherlands with three- or four-yearly measurement waves. Using all available waves, we included 39 genetic, personal, socio-cultural, and environmental characteristics. One municipality satisfied the three BZ criteria. In comparison with participants in other municipalities in the same province and other provinces in the Netherlands, BZ-participants more often had a polygenic risk score linked to longevity, smoked less, consumed less alcohol and more fruit, biked more minutes, did more often paid work, practiced singing more often, attached higher importance to religion, and lived in a more walkable and livable environment. In contrast, BZ-participants had a slower walking speed, more depressive symptoms, felt less purpose in life, had a larger waist circumference, walked and did sports less often, consumed less vegetables, and exchanged less instrumental support. Other indicators of their physical and mental health and social connectedness did not substantially differ from non-BZ-participants. Rather than clues to healthy aging, our findings suggest factors conducive to longevity regardless of impaired health.