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Impact of nutrition on the ageing process

Published online by Cambridge University Press:  21 November 2014

John C. Mathers*
Affiliation:
Human Nutrition Research Centre, Institute for Ageing and Health, Newcastle University, Campus for Ageing and Vitality, Newcastle upon TyneNE4 5PL, UK
*
*Corresponding author: J. C. Mathers, email john.mathers@ncl.ac.uk
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Abstract

Human life expectancy has been increasing steadily for almost two centuries and is now approximately double what it was at the beginning of the Victorian era. This remarkable demographic change has been accompanied by a shift in disease prevalence so that age is now the major determinant of most common diseases. The challenge is to enhance healthy ageing and to reduce the financial and social burdens associated with chronic ill health in later life. Studies in model organisms have demonstrated that the ageing phenotype arises because of the accumulation of macromolecular damage within the cell and that the ageing process is plastic. Nutritional interventions that reduce such damage, or which enhance the organism's capacity to repair damage, lead to greater longevity and to reduced risk of age-related diseases. Dietary (energy) restriction increases lifespan in several model organisms, but it is uncertain whether it is effective in primates, including humans. However, excess energy storage leading to increased adiposity is a risk factor for premature mortality and for age-related diseases so that obesity prevention is likely to be a major public health route to healthy ageing. In addition, adherence to healthy eating patterns, such as the Mediterranean dietary pattern, is associated with longevity and reduced risk of age-related diseases.

Type
Full Papers
Copyright
Copyright © The Author 2014 

For nearly 200 years, human life expectancy has been increasing at approximately 2 years per decade and shows little indication of reaching a plateau( Reference Kirkwood 1 ). Much of the early benefit was derived from reduced childhood mortality from infectious diseases, but, since the mid-twentieth century, the gains have been due mainly to reduced mortality in later life. The latter can be attributed not only to better health care but also to the effects of economic growth and to public health policies including those that have restricted tobacco use and improved road traffic safety( Reference Mackenbach, Karanikolos and McKee 2 ). Despite these improvements, globally, there are large inequalities with countries in sub-Saharan Africa, notably Swaziland, Chad, Guinea-Bissau and South Africa, having life expectancy at birth which is little over half of that in the most favoured countries including Monaco, Macau, Japan and Singapore( 3 ). Within Europe, improvements in life expectancy in Western Europe over the past four decades have not been achieved in Eastern Europe because of political and macro-economic issues and of a failure to implement effective health policies( Reference Mackenbach, Karanikolos and McKee 2 ). Similar socio-economic gradients in life expectancy have also been observed within countries, and Marmot( Reference Marmot 4 ) has estimated that 2·5 million years of life are potentially lost annually to premature mortality in England through the effects of inequalities in health.

Ageing is the major risk factor for most common chronic diseases( Reference Rae, Butler and Campisi 5 ) including cancers( Reference DePinho 6 ), CVD and stroke( Reference Feigin, Lawes and Bennett 7 ) and dementia( Reference Hebert, Weuve and Scherr 8 ). As a consequence, the gain in years of life over the past few decades has been accompanied by additional years of chronic poor health so that the greatest proportion of total expenditure on health care is now concentrated in the last few years of life. Interventions that reduce morbidity in later life are likely to have significant financial and social benefits, in addition to gains in individual well-being.

Biology of ageing

Ageing is characterised by progressive, time-dependent loss of function and increased likelihood of death. This loss of function includes widely recognised, relatively rapid processes such as the loss of female fertility following the menopause and much more insidious declines in brain volume and in skeletal muscle mass that can lead to cognitive and physical frailty, respectively. There is no evidence that ageing per se is genetically determined (or programmed)( Reference Kirkwood 9 ), and the ageing phenotype appears to result from the gradual accumulation of damage to all the cell's macromolecules, such as DNA, proteins and lipids( Reference Kirkwood 1 ). Damage to DNA is not confined to the nuclear genome and there is good evidence of increasing burden of mitochondrial DNA mutations with increasing age in humans (Fig. 1)( Reference Greaves, Barron and Plusa 10 , Reference Greaves, Elson and Nooteboom 11 ). Damaged (unfolded) proteins also accumulate with age( Reference Lopez-Otin, Blasco and Partridge 12 ), and it seems likely that long-lived proteins, i.e. those that turnover slowly, if at all, may be at the greatest risk of acquiring damage with age( Reference Toyama and Hetzer 13 ). For example, the accumulation of damaged crystallin in the human lens with age leads to cataract( Reference Toyama and Hetzer 13 ), which is the most common cause of blindness. The structure and function of cells and of organelles depend on the composition and integrity of membrane phospholipids. These phospholipids are rich in PUFA that are susceptible to oxidative damage, and peroxidation of membrane phospholipid acyl chains is hypothesised to play a causal role in the ageing process( Reference Pamplona 14 ). As one would expect, age-related macromolecular damage has profound effects on cell function, and such dysfunction is likely to be most pervasive when it affects stem cells that are essential for the normal maintenance of mitotic tissues and for tissue repair following disease, surgery or other trauma. During ageing, stem cells may (1) become depleted through loss of capacity for self-renewal, (2) lose their ability to generate appropriately differentiated cell lineages, (3) become moribund because of senescence or (4) acquire genetic and epigenetic damage that initiates tumorigenesis( Reference Liu and Rando 15 ).

Fig. 1 Accumulation with age of mutations in mitochondrial DNA shown as % crypts with respiratory chain defects in biopsies of colorectal mucosa from healthy humans. From Greaves et al. (2010)( Reference Toyama and Hetzer 13 ). R 2= 0·951.

In a recent review, Lopez-Otin et al. ( Reference Lopez-Otin, Blasco and Partridge 12 ) proposed nine tentative hallmarks of ageing that are common to many organisms, including mammals. These hallmarks include the following factors: genomic instability; telomere attrition; epigenetic alterations; loss of proteostasis; deregulated nutrient sensing; mitochondrial dysfunction; cellular senescence; stem cell exhaustion; altered intercellular communication (Fig. 2)( Reference Lopez-Otin, Blasco and Partridge 12 ). In selecting these hallmarks, Lopez-Otin et al. ( Reference Lopez-Otin, Blasco and Partridge 12 ) searched for factors that met the following criteria: (1) it occurs during ageing; (2) experimental enhancement of the factor accelerates ageing; (3) experimental amelioration of the factor slows ageing and so increases healthy lifespan. Lopez-Otin et al. ( Reference Lopez-Otin, Blasco and Partridge 12 ) recognised that evidence for the third criterion was often limited.

Fig. 2 Hallmarks of ageing proposed by Lopez-Otin et al. (2013)( Reference Lopez-Otin, Blasco and Partridge 12 ).

Although there is no ‘death gene’, population genetics studies have shown that about 25 % of the inter-individual variation in lifespan can be accounted for by heredity, and it seems likely that the underlying genetic factors influence ageing through effects on somatic maintenance( Reference Kirkwood 1 ). The remaining 75 % of the variation is due to environmental factors and stochastic events. In other words, the ageing process is plastic and interventions that increase longevity, and which reduce susceptibility to age-related diseases, are those that reduce macromolecular damage and/or which enhance the cell's ability to repair such damage. The ubiquitous causes of molecular damage include inflammation, metabolic stress and oxidative stress/redox changes. Some inter-individual differences in capacity to cope with macromolecular damage are genetically encoded. For example, the 50-fold difference in lifespan between the Atlantic bay scallop (Argopecten irradians) and the sessile giant clam (Tridacna derasa) appears to be due, at least in part, to more effective somatic maintenance in the giant clam( Reference Ungvari, Csiszar and Sosnowska 16 ). In humans, diseases characterised by accelerated ageing such as Werner's syndrome, Cockayne's syndrome and xeroderma pigmentosum are caused by inherited defects in the machinery responsible for DNA repair.

Nutritional modulation of the ageing process

Since the ageing phenotype results from the accumulation of damage to the cell's macromolecules, nutritional interventions that reduce ageing must do so because they reduce the amount of damage sustained by the cell and/or because they enhance the capacity of the cell, tissue or organism to repair, or to cope with, that damage. Genetics-based studies( Reference Kenyon 17 , Reference Bishop, Lu and Yankner 18 ), and intervention studies with pharmaceutical agents such as rapamycin( Reference Harrison, Strong and Sharp 19 ), have strengthened the evidence for the plasticity of the ageing process, and it is apparent that modulation of a relatively small number of pathways central to energy and nutrient sensing and to cellular defence is key to the ageing process. Investigation of these same processes is likely to reveal how nutrition influences ageing.

For at least 80 years, it has been apparent that nutrition modulates the ageing process. The earliest unequivocal evidence for the impact of nutrition on ageing came from studies in rodents showing that dietary restriction (DR) – providing animals with less food than they would eat under ad libitum conditions – increased lifespan and reduced (or delayed) the development of age-related diseases. DR (usually energy restriction while ensuring adequate nutrient supply) is now a very well-established experimental paradigm that extends lifespan and healthspan in many species( Reference Nakagawa, Lagisz and Hector 20 , Reference Simons, Koch and Verhulst 21 ). However, note that the effects of DR on lifespan can be heterogeneous, even within the same species, and that there is evidence that DR can reduce lifespan in some inbred strains of mice( Reference Liao, Rikke and Johnson 22 ). The effect of DR in humans is not known, and both practical and ethical constraints mean that a direct test of the hypothesis is challenging; however, two recent studies have attempted to test the hypothesis in another primate – the rhesus monkey. One of these studies reported apparently greater longevity in rhesus monkeys exposed to 30 % DR throughout adulthood( Reference Colman, Anderson and Johnson 23 ). In contrast, the other study found no effect on lifespan regardless of the stage in the life course at which DR was introduced( Reference Mattison, Roth and Beasley 24 ). Several features of the studies, including differences in dietary regimen, might explain the divergent effects on lifespan, but none of these was conclusive( Reference Austad 25 ). However, in both studies, the dietary-restricted animals were leaner and had a lower burden of age-related diseases. Translating these outcomes to humans suggests that avoiding obesity may improve healthy ageing, and, indeed, there is strong evidence for greater risk of death when BMI is in the overweight and, especially, obese range( 26 ).

Obesity and ageing

The Prospective Studies Collaboration pooled data from fifty-seven human prospective studies involving approximately 900 000 adult participants to investigate the relationships between BMI at baseline and subsequent mortality( 26 ). Most studies were based in Western Europe or North America, and to minimise potential confounding due to current ill health, deaths in the first 5 years of follow-up were excluded. For most of the common causes of death, including CVD, there was strong evidence of progressively greater risk of death with increasing BMI above the minimum in the range of 22·5–25 kg/m2. For some cause-specific mortality, e.g. cancer, there was greater risk with BMI < 20 kg/m2( 26 ). In addition, there is evidence that increased adiposity in adulthood has adverse effects on long-term health. Compared with women who were lean (BMI 18·5–22·9 kg/m2) at age 18 years of age and who remained weight stable in adult life, those who gained weight in midlife had reduced likelihood of healthy survival after the age of 70 years( Reference Sun, Townsend and Okereke 27 ). In this case, ‘healthy survival’ was defined as having no history of major chronic diseases and no substantial cognitive, physical or mental limitation( Reference Sun, Townsend and Okereke 27 ). Women who were overweight at 18 years of age, regardless of subsequent weight change, had reduced healthy survival and those who were overweight at 18 years of age and gained at least 10 kg in midlife were five times less likely to enjoy healthy survival after 70 years of age( Reference Sun, Townsend and Okereke 27 ).

Being obese, or carrying the fat mass and obesity-associated protein encoding gene (FTO) risk allele for overweight and obesity, is associated with changes in brain structure, which are consistent with more rapid brain ageing( Reference Ho, Stein and Hua 28 ). Such results from imaging studies correlate positively with evidence from epidemiological studies showing that overweight and obesity in midlife are associated with a greater risk of dementia( Reference Anstey, Cherbuin and Budge 29 ). Obesity and sedentary behaviour (a potential causative factor) are associated with an increased risk of molecular and cellular damage and, if sustained, with an increased risk of all common age-related diseases due, at least in part, to the damaging effects of chronic, low-level inflammation( Reference Handschin and Spiegelman 30 ). Given that obesity-related behaviours (diet and physical activity) track from childhood into adulthood( Reference Craigie, Lake and Kelly 31 ), effective interventions that prevent obesity in childhood may have lifelong benefits.

Dietary patterns and human ageing

Nutrition is critical for health and well-being at all stages in the life course, and, indeed, the nutrition of one generation may influence ageing in the next generation. While nutrition has immediate effects on metabolism and health, nutritional exposures can have very long legacies. This is exemplified by the impact of maternal nutrition during pregnancy and of nutrition in early postnatal life on ageing (reviewed by Langie et al. ( Reference Langie, Lara and Mathers 32 )). For example, we have shown recently that a nutritional insult during pregnancy and lactation (maternal folate insufficiency), especially when followed by a second nutritional insult (high fat feeding from weaning), may reduce genomic defence mechanisms in the adult offspring brain, i.e. expression of base excision repair genes (a DNA repair system that corrects the lesions caused by oxidative damage)( Reference Langie, Achterfeldt and Gorniak 33 ).

It is probable that many dietary factors including total energy intake relative to energy needs (which determines the risk of obesity), specific nutrients and other non-nutrient bioactive constituents, individually and collectively, influence the accumulation of macromolecular damage within the cell and, therefore, the ageing process. For example, we have observed that the capacity for nucleotide excision repair (a DNA repair system that removes large DNA adducts) is reduced in those with a higher BMI, even among young, healthy adults( Reference Tyson, Caple and Spiers 34 ). More broadly, there is evidence that nutritional intake and nutritional status influences DNA repair( Reference Tyson and Mathers 35 ), and these nutritional factors may explain some of the substantial inter-individual variation in DNA repair capacity in humans( Reference Caple, Williams and Spiers 36 ). Investigation of such complex interrelationships is challenging especially in human epidemiology, with difficulties in exposure measurement( Reference Fave, Beckmann and Draper 37 , Reference Penn, Boeing and Boushey 38 ) and with substantial risks of confounding. The more recent focus on dietary patterns offers promise not only in identifying associations with healthy ageing but also in providing the evidence base for the development of public health interventions. The strongest evidence for links between a dietary pattern and ageing is that for the Mediterranean diet – a dietary pattern which is characterised by high consumption of plant-based foods, moderate-to-high consumption of fish and low intakes of dairy foods and meats and meat products( Reference Trichopoulou, Orfanos and Norat 39 ). In addition, meta-analysis has shown that adherence to the Mediterranean diet is associated with substantial reductions in the risk of several major age-related diseases including CVD, cancers and neurodegenerative diseases( Reference Sofi, Abbate and Gensini 40 ). Such observational evidence has been strengthened considerably by a recent human intervention study that has demonstrated primary prevention of CVD with Mediterranean diet-based interventions( Reference Estruch, Ros and Salas-Salvado 41 ).

Concluding comments

This is an exciting time for research on nutrition and ageing. It is now evident that the ageing phenotype is due to the accumulation of macromolecular damage and that the ageing trajectory is plastic and responds to dietary, and other, interventions. In addition, there is reason to hope that we will soon have a better understanding of the molecular mechanisms through which nutrition can enhance healthy ageing. At a public health level, we need effective interventions to improve dietary behaviours so that we can reap the rewards of greater health and well-being in later life( Reference Mathers 42 ). To date, research on such interventions has been hampered by the lack of appropriate outcome measures since the biological complexity of the ageing process means that there is no single, simple and reliable measure of how healthily someone is ageing. To help address this research gap, we have proposed, tentatively, a panel of outcome measures based on the concept of the ‘Healthy Ageing Phenotype’( Reference Franco, Karnik and Osborne 43 ), which could be deployed in community-based, lifestyle interventions on healthy ageing( Reference Lara, Godfrey and Evans 44 ).

Acknowledgements

The present study was supported by the Centre for Ageing & Vitality and the LiveWell Programme, both of which are funded through the Lifelong Health and Wellbeing cross-council initiative managed by the Medical Research Council (MRC) on behalf of the funders: Biotechnology and Biological Sciences Research Council; Engineering and Physical Sciences Research Council; Economic and Social Research Council; MRC; Chief Scientist Office of the Scottish Government Health Directorates; National Institute for Health Research (NIHR)/the Department of Health; the Health and Social Care Research & Development of the Public Health Agency (Northern Ireland); and the Wales Office of Research and Development for Health and Social Care and the Welsh Assembly Government. These funders had no role in the design and analysis of the study or in the writing of this article.

There are no conflicts of interest.

References

1 Kirkwood, TB (2008) A systematic look at an old problem. Nature 451, 644647.CrossRefGoogle Scholar
2 Mackenbach, JP, Karanikolos, M & McKee, M (2013) The unequal health of Europeans: successes and failures of policies. Lancet 381, 11251134.Google Scholar
3 Index Mundi (2013) http://www.indexmundi.com/g/r.aspx?t = 0&v = 30 (accessed accessed 21 October 2013).Google Scholar
4 Marmot, M (2010) Fair Society, Health Lives. Strategic Review of Health Inequalities in England post-2010. London: The Marmot Review, University College London.Google Scholar
5 Rae, MJ, Butler, RN, Campisi, J, et al. (2010) The demographic and biomedical case for late-life interventions in aging. Sci Transl Med 2, 40cm21.Google Scholar
6 DePinho, RA (2000) The age of cancer. Nature 408, 248254.Google Scholar
7 Feigin, VL, Lawes, CM, Bennett, DA, et al. (2003) Stroke epidemiology: a review of population-based studies of incidence, prevalence, and case-fatality in the late 20th century. Lancet Neurol 2, 4353.Google Scholar
8 Hebert, LE, Weuve, J, Scherr, PA, et al. (2013) Alzheimer disease in the United States (2010–2050) estimated using the 2010 census. Neurology 80, 17781783.Google Scholar
9 Kirkwood, TB (2005) Understanding the odd science of aging. Cell 120, 437447.Google Scholar
10 Greaves, LC, Barron, MJ, Plusa, S, et al. (2010) Defects in multiple complexes of the respiratory chain are present in ageing human colonic crypts. Exp Gerontol 45, 573579.Google Scholar
11 Greaves, LC, Elson, JL, Nooteboom, M, et al. (2012) Comparison of mitochondrial mutation spectra in ageing human colonic epithelium and disease: absence of evidence for purifying selection in somatic mitochondrial DNA point mutations. PLoS Genet 8, e1003082.Google Scholar
12 Lopez-Otin, C, Blasco, MA, Partridge, L, et al. (2013) The hallmarks of aging. Cell 153, 11941217.Google Scholar
13 Toyama, BH & Hetzer, MW (2013) Protein homeostasis: live long, won't prosper. Nat Rev Mol Cell Biol 14, 5561.CrossRefGoogle ScholarPubMed
14 Pamplona, R (2008) Membrane phospholipids, lipoxidative damage and molecular integrity: a causal role in aging and longevity. Biochim Biophys Acta 1777, 12491262.Google Scholar
15 Liu, L & Rando, TA (2011) Manifestations and mechanisms of stem cell aging. J Cell Biol 193, 257266.Google Scholar
16 Ungvari, Z, Csiszar, A, Sosnowska, D, et al. (2013) Testing predictions of the oxidative stress hypothesis of aging using a novel invertebrate model of longevity: the giant clam (Tridacna derasa). J Gerontol A Biol Sci Med Sci 68, 359367.CrossRefGoogle ScholarPubMed
17 Kenyon, CJ (2010) The genetics of ageing. Nature 464, 504512.Google Scholar
18 Bishop, NA, Lu, T & Yankner, BA (2010) Neural mechanisms of ageing and cognitive decline. Nature 464, 529535.CrossRefGoogle ScholarPubMed
19 Harrison, DE, Strong, R, Sharp, ZD, et al. (2009) Rapamycin fed late in life extends lifespan in genetically heterogeneous mice. Nature 460, 392395.CrossRefGoogle ScholarPubMed
20 Nakagawa, S, Lagisz, M, Hector, KL, et al. (2012) Comparative and meta-analytic insights into life extension via dietary restriction. Aging Cell 11, 401409.Google Scholar
21 Simons, MJ, Koch, W & Verhulst, S (2013) Dietary restriction of rodents decreases aging rate without affecting initial mortality rate – a meta-analysis. Aging Cell 12, 410414.CrossRefGoogle ScholarPubMed
22 Liao, CY, Rikke, BA, Johnson, TE, et al. (2010) Genetic variation in the murine lifespan response to dietary restriction: from life extension to life shortening. Aging Cell 9, 9295.Google Scholar
23 Colman, RJ, Anderson, RM, Johnson, SC, et al. (2009) Caloric restriction delays disease onset and mortality in rhesus monkeys. Science 325, 201204.Google Scholar
24 Mattison, JA, Roth, GS, Beasley, TM, et al. (2012) Impact of caloric restriction on health and survival in rhesus monkeys from the NIA study. Nature 489, 318321.CrossRefGoogle ScholarPubMed
25 Austad, SN (2012) Ageing: mixed results for dieting monkeys. Nature 489, 210211.CrossRefGoogle ScholarPubMed
26 Prospective Studies Collaboration (2009) Body-mass index and cause-specific mortality in 900 000 adults: collaborative analyses of 57 prospective studies. Lancet 273, 10831096.Google Scholar
27 Sun, Q, Townsend, MK, Okereke, OI, et al. (2009) Adiposity and weight change in mid-life in relation to healthy survival after age 70 in women: prospective cohort study. BMJ 339, b3796.CrossRefGoogle ScholarPubMed
28 Ho, AJ, Stein, JL, Hua, X, et al. (2010) A commonly carried allele of the obesity-related FTO gene is associated with reduced brain volume in the healthy elderly. Proc Natl Acad Sci U S A 107, 84048409.CrossRefGoogle ScholarPubMed
29 Anstey, KJ, Cherbuin, N, Budge, M, et al. (2011) Body mass index in midlife and late-life as a risk factor for dementia: a meta-analysis of prospective studies. Obes Rev 12, e426e437.Google Scholar
30 Handschin, C & Spiegelman, BM (2008) The role of exercise and PGC1α in inflammation and chronic disease. Nature 454, 463469.Google Scholar
31 Craigie, AM, Lake, AA, Kelly, SA, et al. (2011) Tracking of obesity-related behaviours from childhood to adulthood: a systematic review. Maturitas 70, 266284.Google Scholar
32 Langie, SA, Lara, J & Mathers, JC (2012) Early determinants of the ageing trajectory. Best Pract Res Clin Endocrinol Metab 26, 613626.Google Scholar
33 Langie, SA, Achterfeldt, S, Gorniak, JP, et al. (2013) Maternal folate depletion and high-fat feeding from weaning affects DNA methylation and DNA repair in brain of adult offspring. FASEB J 27, 33233334.Google Scholar
34 Tyson, J, Caple, F, Spiers, A, et al. (2009) Inter-individual variation in nucleotide excision repair in young adults: effects of age, adiposity, micronutrient supplementation and genotype. Br J Nutr 101, 13161323.Google Scholar
35 Tyson, J & Mathers, JC (2007) Dietary and genetic modulation of DNA repair in healthy human adults. Proc Nutr Soc 66, 4251.Google Scholar
36 Caple, F, Williams, EA, Spiers, A, et al. (2010) Inter-individual variation in DNA damage and base excision repair in young, healthy non-smokers: effects of dietary supplementation and genotype. Br J Nutr 103, 15851593.CrossRefGoogle ScholarPubMed
37 Fave, G, Beckmann, ME, Draper, JH, et al. (2009) Measurement of dietary exposure: a challenging problem which may be overcome thanks to metabolomics? Genes Nutr 4, 135141.Google Scholar
38 Penn, L, Boeing, H, Boushey, CJ, et al. (2010) Assessment of dietary intake: NuGO symposium report. Genes Nutr 5, 205213.CrossRefGoogle ScholarPubMed
39 Trichopoulou, A, Orfanos, P, Norat, T, et al. (2005) Modified Mediterranean diet and survival: EPIC-elderly prospective cohort study. BMJ 330, 991.Google Scholar
40 Sofi, F, Abbate, R, Gensini, GF, et al. (2010) Accruing evidence on benefits of adherence to the Mediterranean diet on health: an updated systematic review and meta-analysis. Am J Clin Nutr 92, 11891196.CrossRefGoogle Scholar
41 Estruch, R, Ros, E, Salas-Salvado, J, et al. (2013) Primary prevention of cardiovascular disease with a Mediterranean diet. N Engl J Med 368, 12791290.CrossRefGoogle ScholarPubMed
42 Mathers, JC (2013) Nutrition and ageing: knowledge, gaps and research priorities. Proc Nutr Soc 72, 246250.Google Scholar
43 Franco, OH, Karnik, K, Osborne, G, et al. (2009) Changing course in ageing research: the Healthy Ageing Phenotype. Maturitas 63, 1319.Google Scholar
44 Lara, J, Godfrey, A, Evans, E, et al. (2013) Towards measurement of the Healthy Ageing Phenotype in lifestyle-based intervention studies. Maturitas 76, 189199.CrossRefGoogle ScholarPubMed
Figure 0

Fig. 1 Accumulation with age of mutations in mitochondrial DNA shown as % crypts with respiratory chain defects in biopsies of colorectal mucosa from healthy humans. From Greaves et al. (2010)(13). R2= 0·951.

Figure 1

Fig. 2 Hallmarks of ageing proposed by Lopez-Otin et al. (2013)(12).