Dietary Restriction

Stochastic dietary restriction using a Markov‐chain feeding protocol elicits complex, life history response in medflies

“…The collective results of these five medfly studies reveal that the longevity response of medflies to food restriction is highly sensitive to the particular method of restriction. This, in turn, suggests that the widespread claim that longevity extension is a universal response to DR (Bertarand et al, 1999;Masoro, 2001Masoro, , 2003 may need to be re-visited -the sign and magnitude of longevity extension in other species may also be highly dependent upon the specific details of the DR method. This is emphasized by recent research on D. melanogaster showing that, contrary to earlier findings on the medfly, mortality rates in cohorts maintained on a protein-restricted (i.e.…”

“…Although protocols for DR are outlined elsewhere (Yu et al, 1985;Weindruch & Walford, 1988;Masoro, 1995;Bertarand et al, 1999), we generalize the concept by considering DR in the broader context of food environments. We classify restriction environments according to food quantity defined as the relative or absolute amount of food available to an individual, food quality defined as dietary composition relative to a predetermined idealized standard, and temporal aspects of food availability defined according to whether an individual's daily access to food is either constant, deterministically variable or stochastically variable.…”

“…Although it is well known that dietary restriction (DR) extends longevity in a wide range of organisms, including yeast (Guarente & Kenyon, 2000;Lin et al ., 2002), nematodes (Kenyon, 1997), Drosophila (Chapman & Partridge, 1996;Clancy et al ., 2002;Mair et al ., 2003;Tu & Tatar, 2003;Mair et al ., 2004;Rauser et al ., 2004) and rodents (McCay et al ., 1935;Masoro, 1988;Weindruch & Walford, 1988;Austad & Kristan, 2003) as well as in several species that are not traditionally used in aging research, including spiders (Austad, 1989) and rotifers (Kirk, 2001), nearly all DR studies have been based on feeding protocols in which food quality, quantity and access are both constant and predictable (Weindruch & Walford, 1988;Bertarand et al ., 1999). Despite the obvious advantages of using standard DR protocols, including technical simplicity, daily predictability and nutritional uniformity, one of the shortcomings of DR studies based on these standard protocols is that they create conditions unlike those found in the wild -conditions in which virtually all animals are subject to large variations in the quality and quantity of food available to them (Andrewartha & Birch, 1974;White, 1976White, , 1978Begon et al ., 1996).…”

Effects of Mild Stresses Applied in Adults on Aging and Longevity

“…a reduction of available food without malnutrition applied throughout adult life or at least for a long period, is often considered to increase longevity and improve healthspan in most of species (reviews in Everitt et al 2010), but this conclusion is probably wrong (reviews in Le Bourg 2010b; Nakagawa et al 2012;Swindell 2012). DR is probably not a mild stress because, whereas mild stresses can increase longevity and severe ones decrease it, DR is more efficient in rodents as its duration and the reduction of food increase (Bertrand et al 1999), except if the malnutrition threshold is reached (Fig. 17.4 in Speakman and Mitchell 2011).…”

Effect of dietary restriction beyond middle age: Accumulation of altered proteins and protein degradation

“…Although DR has been applied to a number of animal species in aging studies (Bertrand et al, 1999), limited information is available on its effect when begun at middle age or later. Table 1presents selected data on the magnitude of mean life span extension by DR beyond middle age (starting at or beyond 10 months of age) and the percentage increase of life span in mice, rats, and hamsters.…”