In this thesis I describe studies of life history traits under variation in nutrition focused on ageing. The predictive adaptive response is a type of plastic response which is advantageous later... Show moreIn this thesis I describe studies of life history traits under variation in nutrition focused on ageing. The predictive adaptive response is a type of plastic response which is advantageous later in life, rather than immediately. We tested with a resource allocation model whether for a relatively short-lived organism, Bicyclus anynana increasing allocation to dispersal capability would be advantageous as an adult, when the individual would be stressed as a larva. This was indeed the case. Using a similar model we tested whether increased lifespan under dietary restriction would be evolutionary conserved. This did not seem to be the case. Then we describe how traits and gene expression in fruit flies (Drosophila melanogaster) was affected by sustained cycles of low and high food, compared to constant food controls. Furthermore we compare predictions from a model, in which the relationship between fecundity and lifespan changes with the age of the flies measured. Lastly we test whether genetic variation in genes described in model organisms under laboratory conditions can be correlated to phenotypic variation in life history traits under natural conditions of the least killifish (Heterandria formosa). Indeed this was the case Show less
This thesis aims to describe the role of glucose metabolism in human longevity and to translate the results to an intervention aimed at improving health in older age in the general population. In... Show moreThis thesis aims to describe the role of glucose metabolism in human longevity and to translate the results to an intervention aimed at improving health in older age in the general population. In the first part, we describe evidence for enhanced glucose metabolism in long-lived families. Middle-aged individuals predisposed to longevity were characterized by enhande insulin action at the level of the skeletal muscle, lower accumulation of intramyocellular lipids and lower nocturnal glucose levels. These results have provided the biological basis upon which health-promoting intervention in older age may be funded. In the second part, we have shonw that an internet-based intervention is effective at increasing physical activity and improving health in an older population. Furthermore, increasing total daily physical activity in sedentary elderly was shown to lead to better metabolic health. Show less